Making a panelled door in stencil card

Recently I was asked by a friend to cover for her on the ‘Foundation in Art & Design Diploma’ course at Central Saint Martins. The day was intended to deal with aspects of model-making relevant to a project the students are currently working on. Each is designing an enclosed space with particular emphasis on the doorway leading into it, so we took the opportunity to focus on doors and the different methods of simulating surfaces.There was no budget available for materials so I had to devise a short practical using whatever small leftovers I could spare. The most promising idea seemed to be working with stencil card since I had a lot of small pieces, and stencil card was available at the CSM college shop if the students wished to take it further.

making a panelled door in stencil card

So I spent a bit of time working out the easiest way to make the traditional panelled door above. I’ve already looked at layering stencil card to create the wall panelling effect below and I also discovered some time ago that stencil card could be scraped with sandpaper leaving a fairly convincing ‘woodgrain’ effect, but I hadn’t combined them much. Also, the panelling below was made by carefully marking out and cutting the layers separately, then just as carefully aligning them while gluing. This is quite demanding! .. I wanted to make it more achievable.

using stencil card for wall panelling and windows

The improved method involves four layers (but as yet only dealing with one side) and the only ‘graining’ done is on the top layer and on the bottom layer where the ‘panels’ are seen. Everything is led by the ‘second layer down’ .. the one shown first in the line-up below, on the left. This is the one which needs to be carefully measured, marked out and cut. These doors are 1:25 scale and I’ve rounded off the UK average for a traditional interior door as .. 198cm high by 76cm wide. If you want to be either very specific or if you’re working in feet and inches, it’s properly 6′ 6″ by 2′ 6″! What happens within that outline is more a matter of taste .. there are no similar ‘standards’ for the size or arrangement of the panels. I’ve cut the first piece of card according to what looks right, but also I’ve observed with 4-panel doors that the top pair are usually longer than the bottom and there’s most often a broader strip across the base of the door for strength. The long thin panel in the middle is not meant as a letter box but it could house one, and the handle or doorknob would be positioned roughly halfway up the door which makes it on average a little less than 1 metre up.

stages in making a panelled door in stencil card

The drawing below should print out on A4 at exactly 1:25 scale and if you’re using this design as a template only the first one needs to be traced or pasted, as I’ve said .. the others are just there to illustrate each stage of layering. It goes like this .. after the first is cut out it should be stuck down onto another scrap of stencil card leaving a small margin around it. Spraymount works well, as long as you don’t intend to treat afterwards with a spirit-based medium because this will dissolve the glue .. otherwise superglue applied with care (very thin lines or dots) works perfectly. Pva wood-glue will grip but not bond very well with the stencil card surface. Trim around the outline of the door using the top stencil layer as a guide then judging by eye cut out all the panel areas a little inside the top-piece outline all around making a little ‘step’ .. as illustrated by stages 2-3 above and below. It may take some practise to get an even strip but it’s too slight to measure/mark. I’ve used the smallest division on the 1:25 scale ruler as a visual guide.

stages of making door using stencil card

This piece is then stuck onto another piece of stencil card and the outer edge trimmed again as before .. before doing this the stencil card which comes underneath needs to be ‘grained’ first because this will show. For these examples I’ve used a small piece of 120 grit sandpaper to grain, pressing firmly down and straight along, using the edge of a metal ruler as a guide. Once all three stencil card layers are stuck together and the door outline trimmed around once more (stage 4 in the line-up above), the fourth and final layer comes on top. This one is applied differently though, in separate pieces. It has to be because the grain of each strip must follow its longest edge .. essential for a convincing look! The task becomes a bit like marquetry in wood, but much easier because the stencil card is easier to cut. I grained a much larger piece of stencil card first and cut the strips from it, and I made these a little narrower to form a final ‘step’ around the panel areas.

colouring stencil card door with ProMarkers

There’s almost no end to what one can use to stain or paint stencil card because, in spite of the linseed oil waterproofing, it will accept both water-based, oil or spirit-based media. I’ve detailed a number of these already in my post February 2015 The art of alternative staining where I’m working with wood, but all will work well on stencil card. In fact many will work better because although a fine-grained wood is often the best option for a good ‘wood’ look when it stains well, it can also be difficult to eliminate the scattering of light specks where the polish or stain has failed to penetrate. Generally stencil card accepts stain a lot better and more evenly.

For the two samples above I used Letraset ProMarkers. The alcohol ink in these covers well and dries quickly, though it stains so well that the lighter scratches tend to disappear. These are ideal if you want something subtle. The ProMarker ink itself dries matte but there is a very slight sheen from the stencil card.

staining stencil card with Marabu GlasArt

If you’d like more shine or even brighter colours another option is using Marabu Glasart glass paints above, or ‘vitrail’ as they’re often labelled. These are spirit-based and, in the case of the Marabu, can be diluted or cleaned up with white spirit. One has the choice of either a silky or a glossy finish dependent on how much is applied. Here for example I brushed the vitrail on thinly and also went over with tissue and cotton bud to remove the excess collected in the raised edges .. if I’d just left it the effect would have been more glossy. Vitrail doesn’t work well as successive coats, because like shellac a further coat just starts to dissolve the one underneath and the results could be patchy.

colouring stencil card with shoe polishes and wood-stains

As shown above, if you’re intending a worn or ‘distressed’ effect I would recommend either a liquid shoe polish (which are almost always water-based) or a water-based wood varnish. These will tend to sit more on the surface rather than staining, and with each of these samples I started to rub or gently scrape after only a few minutes, before fully dry .. achieving a properly ‘chipped’ look fairly easily. These are, from left to right, Wickes ‘Quick-dry Woodstain’ mahogany; Cherry Blossom brown shoe polish, Kiwi ‘Wax Rich’ black shoe polish. Stencil card will warp a little with water-based media but not as much as other cardboards and, once dry, it is easier to bend carefully back into shape.

Conventional wood-stains also worked well .. both spirit and water-based. The middle one has a light coat of Colron ‘Georgian Oak’ and to the right I have used a water-based ‘Dark Oak’ wood-stain from Flints in London. The spirit-based stain has remained fairly matte whereas the water-based dried to a slight sheen. Spirit-based stains will also infiltrate quickly to the other side, even when more than one layer .. worth bearing in mind if this will be seen.

colouring stencil card with shoe polishes and wood-stains

Lastly, for the pale sample to the left I tried Osmo Dekowachs ‘Transparent White’. This is a specialist wax-based paint I was using in Germany which I still have some of, though these paints are also available in the UK. Like Humbrol enamels I’ve found that these paints will fix on almost anything. The first coat of Dekowachs is always matte and one has to build up a shine with further coats.

Poor substitute stencil card

For those of you interested in what I do with stencil card as I’ve described in my article Working with stencil card under ‘constructing’ in the Materials section, I have to warn you that there’s an inferior substitute appearing in some of the UK sources I’ve listed. The proper, traditional material I’ve always relied on is an attractive honey/ochre colour, is 375 microns thick and smells very noticeably of linseed oil. I first noticed the ‘poor’ stuff at 4D modelshop who, I’m assuming, had been forced to accept what started to come from their usual supplier, but now I’ve seen the same change in University of the Arts college shops which suggests that this may become more widespread. The inferior type is a darker, dullish brown, seems a little thicker; and has a very different and far less agreeable smell. More importantly .. it is a little tougher to cut, certainly doesn’t cut as sharply, frays at the edges much more easily, and the method I recommend for ‘graining’ the surface with sandpaper just doesn’t work! The surface merely disintegrates, becoming very ‘wooly’ and loses further definition when stained or painted. This stuff may still offer some advantages over more regular thin white card, for its strength and for basic cutting of delicate forms .. but in other respects and for my purposes it’s pretty useless!

comparison of different stencil card types

My advice is to speak directly to the supplier if you are buying stencil card online .. check for sure that it is the standard ‘honey’ colour and not the dull brown, and that it is 375 microns thick (because there’s also a thinner 250 micron version sometimes sold in its place). The other day I bought the proper stuff from Flints in London, and I’m fairly sure that A.S.Handover and Wrights of Lymm will still be supplying it. These three also offer by far the best prices!

Making a non-slip ‘gripping board’ and a bench hook

polyester grip fabric

I would imagine you’ve all seen this material or something similar .. textured rubber sheets for placing underneath rugs or mats to stop them sliding about. I’d bought this version from Poundland a few weeks ago for another idea which in the end didn’t work and so it was pure coincidence that I had it still lying around when I had to cut a lot of Pvc piping for another project. I’ve never bought myself a proper bench vise .. that probably says something about me, though I don’t know what .. and in the past I’ve made do with something like the setup below, the pipe slightly raised on a cutting mat with perhaps some kind of coarse cloth underneath for extra grip. It’s always worked, more or less, but it’s never been comfortable. Cutting mats grip the table well enough for normal knife cutting but rather lose it when the force acts across them .. such as when sawing.

trying to support Pvc pipe for cutting on table

So I tried a few cut pieces of this grip liner underneath and pressed down firmly in position as I would normally do, and I have to say that it worked incredibly well! Although there was a little give, it felt as if the pipe was in some kind of vise. By the way, as you’ve seen .. for once I prefer the American spelling as opposed to ‘vice’!

polyester grip fabric as support for cutting or sanding

I could have just left it like that and it would have been enough of an improvement, but I felt I was onto something and wanted to make a proper ‘gripping block’. I clad both sides of a piece of 8mm MDF with the material, using double-sided carpet tape to stick it down. The carpet tape needs to fill the surface, otherwise the grip material may ruck when the block is used. I thought initially of using rubber glue to attach the material but the carpet tape holds it well enough in place and it means that it can be easily replaced.

cutting block surfaced with polyester grip fabric

I call this a ‘gripping board’ rather than a ‘cutting board’ or mat because I hadn’t intended it to be cut ‘on’ so much, it’s more about helping to hold things steady while cutting slightly ‘off’ the edge of it, but there’s no reason why it couldn’t be used for both especially if a softer base such as chipboard is used. I found that the board gripped anything, round or flat .. plastic, wood or metal. It was just as beneficial when sanding ends or edges, as below.

sanding with gripping block underneath

I tried various thin strips or rods of metal which I’d hitherto only been able to cut using a small metal vise I have .. and it was, again, almost like having a vise! I find it bothersome to set up the vise every time I want to do this and it’s difficult to keep the surface of the metal undamaged.

using gripping block for cutting metal

I found it worked even better after I made a small ‘finger block’ surfaced with the grip fabric which meant that I could press down more firmly without crooking the fingers uncomfortably.

using gripping block with additional 'finger plate'

I’ve always thought I should make a bench hook so this was a good time to try my own augmented version! I just used a piece of laminated chipboard I had (this one 15cm wide, 20cm long) attaching end-pieces of timber (25mm x 15mm) firmly screwed. The screw-heads need to be countersunk!

simple bench hook build

The ‘bench hook’ is so-called because it hooks along the front edge of a work table to provide steadiness while sawing .. at least on the forward stroke! They have been around for centuries, and making one often used to be the first project in school woodworking classes. Here, below, are a couple of manufactured ones .. from http://www.badaxetoolworks.com

manufactured bench hooks

If I’d bothered to look at examples like these before I very hastily put mine together I would have made the timber end-pieces a little short on the right side (for right-handers) as shown above, so that the block could be sawn ‘on’ .. but I wasn’t using the right kind of wood for this anyway.

Nevertheless my idea of covering the working surfaces on both sides with the grip fabric turned out to be a significant improvement, because it gave even more steadiness on both forward and back strokes. Since it is only attached with double-sided tape the fabric can be easily replaced if it gets too damaged.

bench hook with grip cladding

using bench hook

I also found it very useful to have both the bench hook and the simple mat for supporting lengths of wood while cutting.

using mat as extra support

 

A quick guide to soldering brass

materials and tools for soldering

I’ve finally managed to update my guide to soldering in the Methods section and I’ve now included photos. Some of these come from my book Model-making: Materials and Methods from 2008 and were taken by Astrid Baerndal. This guide focuses on soldering small constructions, rather than the more common electrical soldering which almost all of the info you’ll find on the subject deals with. As you will see, ‘constructional’ soldering involves some differences in method; the materials are different and quite often stronger tools are needed. For the moment I’ve confined this guide to simple soldering ‘on the flat’ and more advanced methods of assembling 3D constructions will follow.

What is soldering useful for?

For model forms which are too thin to make to proper scale in other materials such as card, wood or plastic .. for example metal bed frames or railings. Occasionally, for bendable metal armatures ..e.g. for figures or trees .. allowing for some careful repositioning. Soldering does not give nearly as strong a bond as welding, and the joints can’t be put under much stress, but there is no reason why properly soldered items shouldn’t last for a long time if cared for.

Most of my teaching work focuses on making 1:25 scale models .. so 0.8mm round brass rod is a convenient thickness for representing slender railings or special items such as the brass bed frame shown below. This bed frame is mainly 0.8mm, but with 1mm at the corners. Most of the 40W soldering irons I’ve tried have had just enough heat output to manage thicker rods .. up to 2mm, the size of standard scaffolding at 1:25 scale.

soldered brass bed frame on drawing

What metals can be soldered?

One of the reasons why I’m updating my soldering info now is that I’ve discovered some new things which call into question what I’ve always been told .. that brass is the only easy option, or at least the most reliable one. I still agree that brass could be the most consistent and the least complicated .. followed by copper, if it’s thin. These are also the two most available from craft or hobby shops in wire, rod or thin sheet form. But I have found ‘gold’ paperclips  to be just as easy and I always assumed this was due to a brass coating ..now I’m not so sure that’s the reason. For example I recently tried silver paperclips, with the same results! I’m looking into other possibilities at the moment and I will update the info here once I’m sure of it. I also found that the ‘welded wire mesh’ commonly available nowadays solders very well .. when I know I tried it years ago with little success! This common mesh is galvanised steel i.e. steel which has been coated with zinc. Apparently paperclips are also made of galvanised steel as a rule, so there may be a connection here.

The simple answer for the moment is that brass is guaranteed to work well, it’s available and reasonably cheap. Other metals such as aluminium or regular steel can be soldered, but require special solder and flux and may need stronger equipment. But if you really want to know what else is possible, just give it a go ..and let me know what you find out!

How soldering works

The metal parts to be joined are heated with the tip of the iron so that they will be hot enough to melt the soft metal solder applied to them. It is important for a lasting joint that the metal itself melts the solder in this way rather than melting solder onto the iron tip and transferring to the joint because this will achieve only a very weak attachment. One could think of it as a form of ‘hot-melt’ gluing, but using a low-melt metal in place of glue sticks and where the material itself has to melt the glue.

soldering in progress

In the photo above I’ve placed the tip of the soldering iron so that it’s touching both pieces of brass rod and as close to the joint as possible. Once this area is hot enough the end of the solder wire just needs to be touched into the joint and a little of it should instantly melt. The iron should be kept in place just long enough to allow the now liquid solder to infiltrate the joint properly .. i.e. not just covering the top but also running to the other side.

If you’re familiar with ‘constructional’ soldering you may ask why there’s something important missing from the above setup .. there’s no sign of any flux applied to the joint. This was purely a demonstration setup and the iron wasn’t even on .. I wanted the joints and the position of the soldering tip to show as clearly as possible. I’ll explain the importance of flux a little further on.

What is needed to do it?

See the end section for recommendations on specific makes, suppliers and price-guidance for the following list:

A soldering iron of at least 30W strength .. 40W better! .. preferably with a flat ‘chisel’ like tip, known as the bit. This means one can press down for maximum contact with the metal surfaces. However, the majority of soldering irons available are supplied with round ‘pencil’ like bits. As some of the older photos here will show, a standard ‘pencil’ bit will work if the iron has a strong enough wattage to generate enough heat, but over the years I’ve found that a flat bit can help a lot more especially when soldering thicker rods! You will also find that the majority of soldering irons on offer are too weak to tackle metal of any thickness beyond a small fraction of a millimetre .. because most are designed for soldering fine circuit connections. These don’t need to be strong .. they’re commonly around 18-25W. A higher wattage such as 40W doesn’t necessarily mean that the iron will reach higher temperatures .. just that it will have more strength to sustain the heat needed for longer. This is important since thicker pieces of metal will conduct the heat away very quickly.

All this makes the search for the right soldering iron and the price options just a little more involved .. but unfortunately there are further things to look out for. Look at the three irons compared below:

At the top is my old Draper model K40P .. 40W/240V .. which came with a ‘chisel’ bit and has worked very reliably for many years now. Notice the screw head at the end of the shaft which means that the soldering bit can be easily extended or removed just by loosening it. The bit supplied with the Draper is about twice as long as what you can see sticking out, which means that there’s plenty to extend as it wears away. Underneath is the iron from the ‘Parkside Soldering Station’, a cheap offer from Lidl a couple of years ago and a peculiar 48W! This iron works reasonably well in terms of heat output and the integrated stand makes it comfortable to use .. but .. the soldering bit is the ‘screw in’ type, and very short .. so short that it’s impossible to press the bit flat against metal without the shaft getting in the way. Unfortunately a rather careless design .. making it useless if you need any control! The third iron shown is a 40W/220V from Silverline, who make fairly inexpensive but often reliable tools. This comes with a ‘pencil’ bit, which is not the best to have .. but the heat output is good, the shaft is slender, and the bit supplied can be extended (the locking screw is not visible in this photo) for more control. This has worked reasonably well so far during our soldering workshops.

soldering bits compared

The type below could also be a good option .. although angled bits are not very common. I found this ‘unbranded’ iron in a £-shop and it has worked very well for a number of years. Perhaps it goes without saying though .. one does need to be extra cautious when using cheap, unbranded electrical goods! Really, if you don’t know how to test the electrical safety or know someone who can, it’s safer to leave well alone!

unbranded soldering iron from a pound-shop

To sum up .. get a recognised brand 40W iron with a relatively slender shaft, a ‘chisel’ bit and/or the option of changing easily by means of a simple screw-locking mechanism, and you can’t go wrong! If possible check that the bit provided is long enough to be extended if need be.

A stand (sometimes supplied with the iron) is essential, both to hold the hot point off the work surface when not in use and to secure the tool in one position on the table. Unfortunately the flimsy sheet-metal ‘stands’ most often supplied never manage the latter! There seems to have been a fairly universal agreement that soldering irons should all have just a little over 1.3 metres of rather inflexible cord . This is not long enough to allow the soldering iron to stay on a work-table without some pull from the cord, unless one has a handy power socket ‘kitchen style’ at worktop height. In short .. the iron will move around a lot, independent of one’s awareness or control, which is worrying considering it can inflict a lot of pain! There’s a cheap solution, shown below, which is to tape whatever ‘stand’ you have to the table. Here I’ve improvised a perfectly adequate stand out of welded wire mesh.

improvised soldering iron stand made from welded wire mesh

Or a more elegant solution is to buy a separate stand unit. This one below is from Antex and costs around £6 .. more on prices later. These stands are weighted, and usually have a sponge attached which must be dampened if used for wiping the iron while working.

Antex soldering iron stand

Solder A soft metal alloy wire which melts on contact with heat to form the ‘glue’ which makes the bond. Up to recent times the standard type was 60%tin-40%lead but now there are many lead-free alloys available. Also common now are ‘multicore’ solders with built-in flux. But I have to say honestly that I’ve had consistently better results over the years using an old-fashioned tin/lead solder and a separate flux.

Flux A liquid or paste which is applied to the joint just prior to soldering and which assists the solder to fuse properly with the metal by preventing the metal surface from oxidising. The flux evaporates as soon as the metal gets hot.

Steel wool or fine emery paper/cloth to clean the metal before soldering. It will be easier to wipe rods clean with fine-gauge steel wool but emery or ‘wet/dry’ paper will also work.

A damp sponge, steel wool or metal files to clean the soldering bit while working. This needs to be done once the iron is hot, but it is not enough just to do it once at the beginning of a session. The hot bit of the iron will blacken again within a minute, so to prevent build-up of this oxidation the cleaning needs to be repeated at least each time the iron is picked up again. This has nothing to do with cleanliness! .. a thick layer of oxidation will prevent much of the heat transferring from the bit to the brass.

Kapa-line foamboard or heavy card on which to mount the template drawing

Caution note: Kapa-line (polyurethane) foamboard is suggested because it is a perfect insulator (will not conduct heat away from the metal) and polyurethane foam resists heat to an extent. Standard (polystyrene) foamboard is not suitable .. this melts too easily! If soldering is done properly the paper covering on the Kapa-line foamboard will scorch but there is little danger of fire or burning of the foam. However, proper care must always be taken! Over almost 10 years of conducting workshops we have experienced nothing more than routine paper scorching .. but this is partly because we, and the people taking part, have always been vigilant! Soldering irons must never be left on when not in use for long periods and must be kept well away from flammable materials.

Spraymount for mounting the drawn template onto the foamboard. I normally use the permanent ‘PhotoMount’ version from 3M.

Masking tape for fixing cut metal to template. The tape will normally resist the heat sufficiently to secure pieces while soldering but the glue softens and in cases where extra time is taken or areas redone these fixings can become very loose and may need to be replaced. Understandably ‘Sellotape’ is not an option because it will melt!

Scalpel (adequate to nick a groove thin brass) or hacksaw for thicker rods. I keep some old scalpel blades for this and I’ve found nicking/snapping brass rod up to 2mm diameter fairly easy.

Also pliers, wire snippers and metal files .. as/when needed.

A workplace with good ventilation! This is essential if you are using a traditional tin/lead solder. In addition, flux will burn off in the process and the fumes can be harmful if allowed to build up or stay around.

Detergent to thoroughly clean work afterwards. The flux component is corrosive and it will continue to eat the metal away if left.

Step-by-step

Draw up the form to be soldered on paper ( I recommend drawing 1:10 first then reducing 40% for 1:25 if working in this small scale ). Copy this and spraymount to foamboard or flat card. This will be the soldering template. I’ve designed the one below so that I can make use of the curved parts of paper clips.

copy of drawing spraymounted to foamboard as soldering template

Clean metal thoroughly with steel wool before cutting small lengths, even if the rod is newly-bought. Brass rod is given a coating to stop it tarnishing too quickly, and this will interfere with the adhesion of the solder if it’s left on. Rubbing with a fine steel wool is the most convenient method, though ‘wet/dry’ or emery cloth will also work.

cleaning brass rod with steel wool

Cut metal pieces to fit and use thin strips of masking tape to secure them in place on the template. Metal edges must fit to touch, so that heat travels. Luckily thin brass rod is surprisingly easy to cut with a scalpel .. just by carefully rolling the blade across it to make a fine groove and then snapping! With this method one can be very precise as to where one cuts. A small metal file such as the one below will be useful for making fine adjustments to the lengths if need be.

pieces of brass being assembled on a railing template

Usually, and especially in the case of railings, quite a number of pieces are needed which have to be precisely the same length .. because most often they have to fit between two horizontals. The best method of achieving this is to make a ‘cutting jig’ .. an ‘L’ shaped piece of card or plastic which serves as a guide for the scalpel blade as shown below.

using a guide to help cutting pieces of brass the same length

Switch the iron on and allow to heat up for a few minutes. Make sure that the iron ‘bit’ (the tip that gets hot) is clean. If not, wipe on damp sponge or steel wool, or use metal file. Some model-makers recommend ‘tinning’ the iron at this point (dipping the very end of the bit in flux and then applying a little solder to it). This may help the heat-flow to the metal if there are problems, but it may not be necessary.

applying flux to a joint

I use a small, old paintbrush to put a little of the flux (whether paste or liquid) onto the joint. I prefer to do this one joint at a time, because if more are fluxed in close proximity the flux on these will evaporate as the first joint is being heated. It may not matter .. it’s just become a habit.

After applying the flux touch the soldering iron bit as near as possible next to the joint, trying to touch both (or at least more than one) of the metal parts. Hold there for a few seconds .. a good initial sign is if the flux immediately start to smoke, meaning that the brass is getting hot enough. If nothing appears to happen try adjusting the angle of the iron for better contact but don’t take the iron away! With the other hand gently touch the solder wire to the joint. A little solder should melt fairly instantly and hopefully run into the joint. Use as little as possible ..though this will take some practise! Some patience may be needed to hold the iron relentlessly in place, or fine-tune the angle, until the solder decides to melt. It’s actually very difficult to describe exactly what leads to a ‘successful’ soldered joint in every case. It has to be tried, and if something works, looks right and feels strong ..you’ll establish a ‘feeling’ for what you did to achieve it after some trial-and-error and a lot of repetition!

soldering in progress

When all joints are done the work can be removed from the template almost immediately .. fine-gauge pieces like this will cool very quickly. The work should then be cleaned carefully ( either with warm running water, toothbrush and detergent .. or the dry method, using steel wool ) to remove remaining flux. If left on this will continue to eat away at the metal.

portion of soldered brass railing cleaned up

I was fairly happy with this result .. I’d managed to keep the bits of brass rod reasonably straight while soldering them. I did have to work on this piece a bit though, apart from thoroughly cleaning up with steel wool. It can often be very difficult to be as minimal as one would like with the solder, and a number of the joints were far too ‘swollen’ looking. Solder is so soft that it can be shaved away with the tip of a scalpel blade, or one can use needle files like the one above to remove the excess. Soldering ‘kits’ often have a desoldering pump thrown in, which is like a spring-loaded syringe. The idea is that excess solder can be quickly sucked away while it is still liquid. I’ve yet to try one of these myself ..mainly because at that point I don’t want to risk knocking the brass pieces out of alignment!

Why is brass the easiest to work with?

Brass is an alloy ..in this case a mixture of copper and zinc. The zinc gives brass a tougher surface and more rigidity than copper, but also makes it less malleable, more brittle. Brass rod is strong enough to maintain its shape and straightness well, but soft enough to be easily cut with hand-tools. For these reasons it is one of the most available metals in a wide variety of fine-scale forms. Copper is softer and can be worked even more easily, but rods of around 1mm thickness would deform too easily and have much less structural rigidity. In addition, copper is an excellent conductor, which means that standard soldering irons would struggle to keep up with the constant heat loss from the joint area.

closeup of different soldering joints

Above is a close-up showing three common types of joint. .. spot, lap and butt..! Underneath are two small pieces of very thin ..0.1mm.. brass sheet which have been attached by melting spots of solder. To the right is the simple form which I have illustrated so far, where two straight pieces just ‘butt’ against each other. Below to the left is the strongest form of joint, where a small length of one piece runs against or ‘overlaps’ the other.

Troubleshooting

If the solder is not melting freely on contact with the heated joint or running off in little beads it can mean that either: ..it may be the wrong kind of solder; the joint is not fluxed or there is not enough; the iron may not be hot enough yet, or strong enough for the work; the bit may need cleaning; the tip shape is not making enough contact or close enough to both pieces of metal …

If all else fails assist the heat-flow either by ‘tinning’ the iron as some recommend or touching the iron tip practically over the joint, melting solder directly on the tip to fall on the joint.

An alternative method

As I’ve suggested, it can be very difficult to keep the pieces of brass exactly where they should be because the masking tape loosens a little as the metal gets hot. If the solder melts and fills the joint quickly this is no problem, but for the various reasons listed this often takes longer. The photo below illustrates a method which I’m far happier with, and which produces far better looking results .. but it’s only worth spending the extra time if the set-up is to be used more than once.

a soldering jig created for a ladder form in brass

For this soldering jig I’ve used some tough ‘greyboard’, a recycled cardboard, of the same thickness as the 1mm rod chosen for the ladder form. I’ve cut and glued a complete template of it onto another cardboard base so that the individual brass pieces lie snuggly in these slots.  I’ve used this jig about 4 times so far and I don’t see why it shouldn’t last for more.

 

Selected suppliers and prices

Brass rod always in straight lengths, never as roll. Cheaper in 1m lengths rather than 300mm. e.g. 4D prices for 1m lengths (April 2015) 0.8mm £0.79, 1mm £0.98, 2mm £1.25

An alternative source is EMA Model Supplies .. for 91cm lengths 0.8mm £0.67, 1.6mm £1.27 .. but choice of thicknesses is very limited.

Solder Silverline 60:40 Tin/Lead Solder (4D £1.80 per 20g, available £4.00 per 100g) works very well! Melting point 183-190C.

Flux

The ‘grease’ type flux I always provide when teaching has always worked well, but I’ve had it for so long that the original container started to disintegrate .. so I don’t know the brand anymore! But one I’ve heard as good is La-Co Regular Soldering Flux Paste available from Screwfix £5.39 per 125g .. for use with copper, brass, lead and zinc.

http://www.screwfix.com/p/la-co-lac-22195-flux-paste-with-brush-in-cap-125g/61072#product_additional_details_container

Another one recognised as reliable is Fluxite Soldering Paste, suitable for copper and brass .. actually most metals other than aluminium (although other metals would require different solders) and can be used with either lead or lead-free solders.

http://www.fernox.com/products/traditional+plumbing+products/solder+and+fluxes/fluxite

On Amazon c.£10 for 100g tin and about the same from Jewson’s. Maplin just stocks the 450g tins for some reason, enough to last a few lifetimes!

Soldering Iron

SolderCraft 40W-230V (supplied with 5mm diameter chisel bit, stand and manual. 4D £20.99) Separate bits available £3.80. Around £18 on Amazon (with chisel bit) ..

From AllElectricRC http://www.allelectricrc.co.uk/ this will cost £13.59 but supplied with a pencil bit .. still worth it ordering an additional chisel bit (AllElectric doesn’t have them)

Draper 71417 40W-230V on Amazon £15.95 (picture shows chisel bit, so I hope it is)

Draper K40P 40W-240V soldering iron

B&Q stocks a 40W soldering iron for £12.85 which looks almost identical to the old Draper model I have, above, and has a ‘chisel’ bit according to the product photos. This should be fine if it has been assembled with enough care.

Bench Stand Silverline brand, 4D £3.65 well worth getting (Antex shown in photo around £6) £5 from Maplin ..

 

See also

David Neat Model-making: Materials and Methods Chapter 4: Working with Metals

C+L Finescale. – go to the ‘Knowledge Centre’ for concise notes on materials and methods, including a chart advising on what solder and flux to use for different metals

http://www.finescale.org.uk/index.php?option=com_content&view=article&id=27&Itemid=2

4D Modelshop – a basic guide to soft soldering

http://modelshop.co.uk/Content/DynamicMedia/cms-uploaded/files/4D_guide-soldering.pdf

The Basic Soldering Guide http://www.epemag.wimborne.co.uk/solderfaq.htm – this is written for its specific use in electronics but much of the advice applies.

Making ‘white card models’ for film or television design

I have fully updated this article, which was originally written a few years ago, and I have added some more illustrations. This form of model-making is, I think, still proving itself invaluable despite increasing competition from the likes of SketchUp. I’m keeping it in the Methods section for the time being, though not sure whether it shouldn’t go with Technical Drawing.

The following aims to serve as an introduction to the purposes of the so-called ‘white card model’ in film/tv design work, what it should include, and the materials one can choose to make it. In the case of the materials and techniques recommended, it is really just an overview of possibilities and doesn’t go into full, step-by-step instruction on how to build. It is important to make the distinction right now between the ‘white card model’ meant in this case and the other case .. the exploratory, often rough and inexact, sometimes coloured, ‘sketch’ model which is often referred to by the same name, especially in the theatre. The ‘white card model’ of the present context is, in many ways, anything but rough and inexact and most often, due to its usual place in the chronology of design steps, it is no longer exploratory.

‘White card models’ explained

Although the film/tv production designer is free to use a wide variety of visual means in developing and recording a set design concept, including rough or ‘sketch’ models during the early stages, the so-called ‘white card model’ produced for the final stages conforms to very specific requirements. It is usually made once the design has been finalised, most often incorporating the detailed technical drawings created for the construction of the set. It is therefore quite literally a three-dimensional ‘blueprint’ of the intended design.

white card model

It is usually not a realistic, atmospheric rendition of what the set will look like, let alone how it will appear in the film. It may offer no information on colour, little on texture and materials, but all the most essential information on space, structure, movable elements and their practical implications. The designer may build a version earlier in the design process to test the design’s three-dimensionality ( to check general proportions, to better visualise filming possibilities etc.) but these things have usually all been worked out by the final stage and here the model made is more of a communicative device than a ‘testing’ tool. It serves as a communication to the whole film crew. It tells the director and the cinematographer exactly how much space there is for whatever action is required for a scene but also gives a summary idea of what will be seen behind it (this supports the value of creating technical drawings/model with some graphic indication of surface textures etc.). In addition it tells the cinematographer, and camera, sound or lighting crews, how much space there will be for equipment and whether any obstacles such as pillars, steps or levels need to be planned for. It gives an overview for the technical crew responsible for building and furnishing a set (or modifying an existing one) of how much work is required. It furnishes the financial administrators with the same overview to help them assess the costs.

The most common scale for this model is 1:50 (or the equivalent 1:48 if Imperial ..feet and inches.. is used). This is usually the scale in which the main technical ground-plans are drafted, and it is generally accepted that this is neither too small to show a significant amount of graphic detail nor to appreciate proportion in relation to the human figure. In any case models in a larger scale i.e.1:25 simply become too big to be manageable. Common types of card can be used, with the drawings spraymounted to them. These are then cut out and assembled to form 3D structures. The ‘rule’ is that anything which has a significant physical bearing on the set space (such as a pillar, steps, changes in floor level, opening doors, railings etc.) needs to be represented in 3D whereas anything which can be ignored from the point of view of space (such as shallow decoration or panelling, light curtains etc.) can be left flat as drawing. I always recommend that, at 1:50 scale at least, one can safely represent most things under 5cm deep (in reality) as flat drawing. 5cm amounts to a thickness of 1mm in a 1:50 scale model. On the other hand, anything protruding 5cm or more should be given that physical thickness in the model! For example a thin modern radiator could be just drawn whereas an older, more ‘bulky’ type really needs to be represented more physically in 3D (at the very least as a separate cutout which is stuck at the correct distance from the wall to convey the object’s total depth). Another common example is bookshelves, which also really do need to be shown in their proper depth however ‘fiddly’ this might seem. This is to ensure that there can be no misunderstandings about the exact spatial limitations of the set, which is of vital importance considering the amount of money in filming-time which such misunderstandings might cost.

One exception to the ‘5cm rule’ may be the floor area .. and this calls for the personal judgement of the designer/maker. In the case of the floor, even differences under 5cm could have a huge physical impact in terms of moving things around, so it would make sense to emphasize these physically in the model. It helps even more if the height indications included on the drawn ground-plan are kept visible .. another good reason for using the actual ground-plan, pasted to the baseboard.

There is always a margin left for personal judgement! Just as there is always room for the personal touch, to be a little bit more personal, creative or even .. aesthetic! .. in how one renders one’s own technical drawings (better still if it actually enhances rather than detracts from the communicative clarity of them!) the same should apply to the white card model. Showmanship may not be strictly necessary in practical terms .. but it can inspire!  Even this kind of model can be stylish as well as functional and, dependant on individual taste, ability and.. most importantly.. time, it can be embellished with graphic detail, structural finesse or effects designed to ‘sell’ the visual concept. Even at the later stages of design development it pays to be truly creative with the model, to be inventive with methods of representation or ‘simulation’. Such experimentation can directly pool into what I call our general ‘creative matrix’ as designers. I wouldn’t say that elements of colour are totally ‘banned’, but particularly here it is important not to upset the overall balance. Colour can become a distraction, giving visual weight to some elements to the detriment of a balanced overall view.

Edwina Camm white card model

Above is part of a white card model made by Edwina Camm for ‘An Instance of the Fingerpost’ an MA Production Design film project at Kingston. Edwina drew her original technical drawings this way .. little needed to be added to create this rich, convincing effect when used for the white card model.

There is another form of ‘white card model’ often used in film which I’d call ‘virtual’ or imaginary .. where a building, structure or even a whole landscape is constructed in precise dimensions even though it will never be physically built in its entirety. These are just as important to the production process because they make sense of how the various embodiments of the ‘set’ (whether CGI, built interiors, realistic physical models made for filming) are meant to fit together. I will be coming back to these later, but for the moment we are still concentrating on white card models for physically built sets.

There now follows a short list of the most significant individual points worth noting:

The base on which the model is mounted should be flat and stable i.e. secure enough to be a good support, not only when transporting the model but also for resting it down even where there are no totally free table-tops available. Production offices are often like this, and certainly studios or locations with sets in progress. Mountboard on its own is never enough! Generally 5mm foamboard will suffice for an A2 size model and 10mm foamboard for A1 and is often a better option than choosing heavier plywood or MDF! However if the foamboard is warped (and the cheaper polystyrene core foamboards often are) this must be first corrected by firm bracing on the underside. Another important extra precaution is protecting the baseboard corners against knocks (perhaps just by gluing triangles of mountboard on the top side). There’s nothing that transmits an impression of carelessness more than a lot of bashed corners! These may well become inevitable with a ‘working’, much-carried cardboard model, but just a little bit of extra strengthening can limit the damage. One needs a balanced attitude with respect to all this .. on the one hand caring about one’s professional appearance but on the other accepting that in a heavily populated working environment one can’t remain too ‘precious’!

White card model for 'Moon' 2009

Model in preparation for the build of the Sarang moon-station for the film ‘Moon’ 2009 on Shepperton Studios K-Stage. Often to save time, and if changes are anticipated, the white card model is mainly held together with pins .. unfortunately these models are always falling apart! Photo courtesy of Gavin Rothery.

The ground level (at least the visible set floor) should also be represented in white rather than bare wood if this is used. There should be a unity .. or rather, the word is homogeneity .. of colour and treatment throughout the model. But it should show very clearly where the floor is ‘the set’ and where it is not, so sometimes it makes sense for the ‘offstage’ to be differently coloured. Most often the master groundplan is used, spraymounted to the baseboard. If this groundplan is properly done, then (sometimes overlooked) elements such as scenery seen through windows will be automatically accounted for in the model. For obvious reasons even small ground surface elements or slight level changes will have an impact on how the space can be used, so these need to be physically represented in the model rather than just drawn. If you’re lucky, slight changes in level are easy to achieve just by layering different thicknesses of card on top of the baseboard. If you’re unlucky and part of the floor sinks below the common ‘0’ level, this is another good reason for using something like 10mm Kapa-line foamboard as a base. The section that sinks can be carefully cut out (a precision job with the scalpel), the paper can be peeled from the back of it and the foam sanded to make it thinner, and the section can then be glued back where it came from .. now a little sunk.

There should always be at least one scale figure included, simply as a familiar indication of scale. In my experience, as long as the essential proportions are right this figure should be as simply conveyed as possible and flat cut-out figures often look better in this context than 3D ones.

Practicals (i.e. working or moving elements) such as doors, shutters or removable parts need to work in the model, or at least be clearly indicated as movable. This should remain within reason ..for example, it is easy enough to half-way cut through card to make a working door but it would be unreasonable to expect a working roller-blind! In cases like this the simpler shortcut would be to make the model with the blinds open and make separate inserts to convey the effect of them down if this is necessary. Even in the simpler case of practical doors it may be better just to glue them ajar to show that they’re practical. Having to flip little bits of cardboard open in the model just to show that they open seems a bit unnecessary and could even be dangerous to the model if nerves are affecting one’s motor-control! It is often necessary to make parts of the model removable so that, especially, interiors can be better seen and to take better photos of these parts. This may directly reflect how the set will be built for filming in which case the so-called ‘floating’ walls will be indicated on the groundplan. Ceilings are a bit of a ‘grey area’ (i.e. often misunderstood) when it comes to the white card model. Strictly speaking if the walls of a studio set are going to be built to a certain height, even if that extends beyond what the camera will see, they should be built to that height in the model. Similarly if a ceiling exists in a used location it should be included, to make it clear where it is, even if the camera is going to avoid it. This would then need to be made detachable. When the ceiling becomes a feature of the design it should definitely be included, but again detachable.

Windows which are meant to be seen through (or any transparent surfaces) need to allow just that in the model, and need to be cut out, and also surfaced on the back with thin acetate to make it clear if they are going to be glazed (this for example is something both the lighting and sound crews will need to consider).

It is a common mistake to forget that something will be seen through a window, or an open door. If the set design has been conceived and developed largely on the drawing board it may be only at the ‘white card model’ stage that this is even considered! By then it may be too late for major alterations or to create more space for backdrops etc. Digital insertion via blue or green screen, or even old-style back projection, may solve a number of problems .. but these also should be planned for earlier in the design process. This is yet another solid argument for starting the physical model process early on, if only as rough ‘sketch’ version.

Edwina Camm white card model

Another example of the illustrative quality of white card models from Edwina Camm, also showing the importance of including the ceiling in this context.

If slender structures just as stair balusters or metal railings (although spatially flat) are left as blocked-in drawings they can create a false impression of space and often completely obscure the effect of the stairs. These are far better represented as cut-outs where humanly possible. An effective and often easier alternative however is to draw these structures with permanent ink on acetate sheet (but the acetate should ideally be matted to differentiate it from glazing).

There should be no short-cuts taken when representing steps, even long, regular flights of them (i.e. sometimes done by representing them as a flat card incline). This can be visually confusing. It is understandable because making them can be tedious, but ‘sandwiching’ foamboard or card to form the correct ‘riser’ (meaning the height of a step) and then simply layering these is one way of making construction much easier.

Should a ‘white card model’ stay white?

I’ve written elsewhere that I don’t consider pure white card to be the right medium at all when it comes to representing, or even just mocking up spaces. I think that at the very least off-white, beige or light-grey should be used because white is far too glaring .. it bounces the light within and around it like a pinball and consequently it gives a misleading impression of interior spaces! But it’s different when copies of the technical drawings are pasted to the surfaces .. there is less glare and, dependent on the style of drawing and the copier settings, often a variety of grey tones.

As I explained earlier, the effect should be monotone, rather than particularly white. The model can even be sprayed, as long as this doesn’t obscure the definition of the drawings.

SCALES AND SIZES

Since the white card model is commonly a pasted, 3D version of the technical drawings  one would assume that these dictate the scale of it .. but this is only partly true. As I’ve said 1:50 (or 1:48) is the most practical scale and the master ground-plans are often drawn in this scale. But the elevations (meaning the vertical faces of walls, structures etc.) may have to be drawn in a larger scale, such as 1:25, if there is a lot of detail. These drawings therefore have to be converted to 1:50 .. i.e. copied half-size.

Most people with some experience of working with scales would not have to think that long to arrive at ‘half-size’, or ‘50% reduction’ when thinking of the conversion from 1:25 to 1:50 .. it seems obvious. However, what if the elevations have been drawn in 1:20 scale and need to become 1:50? Less obvious, isn’t it? To solve this little mental problem we have to go back to ‘1:25 to 1:50’ and look at what we might have done. If we divide 25 into 50 we get ‘2’ .. if we then divide 2 into 100 we get ’50’. That’s the percentage reduction. So .. 20 into 50 gives us ‘2.5’ and 2.5 into 100 gives us ’40’ .. so this time it’s 40% reduction.

A common mix-up that arises when thinking or talking about models is between ‘scale’ and ‘size’. For example, a 1:50 scale model will be ‘smaller’ both in scale and physical size than the same structure modelled at 1:25 scale but the 1:50 version might sometimes be referred to as a ‘larger’ model because it enables a ‘larger’ area of the real thing to be modelled. To avoid the confusion one should make a habit of referring to ‘smaller’ or ‘larger’ only in terms of scale, i.e. a ‘larger’ model is one that is made to a larger scale even if it ends up a physically smaller portion of the whole. The scale 1:20 is a ‘larger’ scale than 1:25 but many people also get confused because, from the way it is written, it appears a smaller value. It may be a little easier when working with Imperial (feet and inches) and referring to ‘half- inch’ or ‘quarter-inch’ scales, more obviously decreasing in size.

By the way, another misunderstanding often arises when confusing dimension and surface area. For example, when asked to double the size of an A4 drawing many might think ‘A4 to A3’ but this, although doubling the surface area, is not doubling the dimensions. To double the dimensions you need to choose the next size up, i.e. A4 to A2.

Even if one has recently completed the technical drawings, before starting a 1:50 or a quarter-inch white card model .. or any scaled model .. one should take a moment to re-acquaint oneself properly with the scale again. One should, for example, look at how small a figure is (average male actor 1.75m high), how high a door might be (average 2m high), but just as importantly how thick a piece of card is needed to represent 5 or 10cm reasonably accurately.

white card model

Above is an illustrative ‘sample’ of white card model, simply made to convey a few of the typical things mentioned above .. and not outwardly expressing any aesthetic! However, it is clean and neat .. in other words the making of it looks cared about. One should never underestimate the importance of this! On the other hand the white card model works for a living .. it gets around, it’s handled and it gets worn at the edges .. so there’s no sense in getting too precious about it.

Wyeth style house

But, there’s nothing to say that the white card model can’t be dressed with some style! The model above was created by Patrick Scalise while a student at Wimbledon College of Art.

VIRTUAL WHITE CARD MODELS

This may seem like a contradiction in modern language but you’ll understand, it’s the best way of describing actual physical scale models made of buildings, structures or landscapes that are never going to exist in their entirety in real size .. but are treated as if they will! If you visit Warner Bros. ‘The Making of Harry Potter’ you’ll see a number of these, alongside other white card models for interiors and other large ‘props’ that were physically built.

Hogwart's white card model

Hogwarts was a very clever, highly complex and meticulously planned creation which brought together CGI, real locations, realistic physical models and full-size builds. This white card model is pivotal in giving the countless people involved a clear and immediate understanding of how each part is meant to go together.

 

MATERIALS AND TECHNIQUES

Foamboard

White foamboard is one of the most common materials used as a structural basis for
these models, together with the thinner mountboard. It is light and very easy to cut, though quality and properties differ widely according to brand and price. Its main advantage is in combining ease of cutting with robustness (i.e. it maintains its straightness while still being soft) but its thickness can also be a bonus when defining proper walls (e.g. 5mm at 1:50 scale represents 25cm). It is manufactured in 3, 5 and 10mm thicknesses, though often only the 5mm is stocked in shops. Cheaper foamboards are filled with a relatively coarse-celled polystyrene which doesn’t stand up to solvent glues or spray-paints, whereas the foam interior in more expensive brands may be denser, giving a cleaner, more solid cut edge and perhaps a slightly more dent-resistant surface. The better brands will usually accept even PVA wood glue quite well for bonding. This is certainly true of the superior polyurethane foam in Kapa-line foamboard which will accept even solvent glues such as UHU and spraypaints. Kapa-line remains straight even under humidity (other foamboards are often quickly warped) and it has the added advantage that the paper layers can be carefully peeled off, either to facilitate bending into curves or to use the foam on its own as a material.

Cutting
When cutting through card with a knife a slightly angled edge is inevitable however upright one tries to keep the blade. The thicker the foamboard the more pronounced this can become. This may not always be visible or matter, but better right-angled edges are needed when gluing two pieces together to make a corner. One possible way of solving this is by cutting just half way through on one side, taking the line carefully round (i.e. with a try square) to the other side and completing the cut in exactly the same place on this side. If the foam edge is uneven this can be gently sanded using a sanding block. In fact if one can use a right-angle sanding block gently enough any foamboard edge can be sanded clean and straight. The fuzzy burr of paper which develops along both sides can be removed by carefully ‘scuffing’ with the sanding block at a 45degree angle. Extra care needs to be taken while working with foamboard not to press down too firmly while steadying the sheet as finger-dents are very easy to get.

Joining
Strong PVA glue (always better to use the ‘wood glue’ type rather than the economy-style ‘school’ glue) will bond foam-to-card well but not instantly, so joints often have to be temporarily taped together with masking tape while setting. One should usually allow at least 15 minutes for this. An alternative ‘trick’ is to insert a few short lengths of double-sided tape along an edge to be glued so that these hold the card pieces temporarily but firmly together while the slower glue (alternating in between) is taking effect. Using a solvent glue such as UHU may be quicker, but it dissolves the foam in the standard brands so clean or effective gluing is not always guaranteed. Coating any foam edges first with slightly diluted PVA will solve this and when dry, UHU or sprays can be used on these edges, but it is rather laborious to go to this trouble.

Bending
Whether curved walls need to be made in either foamboard or mountboard the method is similar. The material needs to be cut half-way through in repeated parallel lines (as little as 2mm apart for a tight curve), making it more flexible. But the grooves only work for bending one way, so for example an ‘s’ curved wall has to be grooved in alternate positions on both sides for it to bend properly into an ‘s’. The walls can be surfaced with paper to hide the grooves, but the curve must be secured (in the right curve) before this is done (if done before it will stop it from bending) and it’s better to use permanent spraymount otherwise a thin paper covering will buckle badly.

Other methods include .. if the superior Kapa-line foamboard is used, the paper layer can be peeled off (either from one or both sides) making it much more bendable without having to score the surface. Perhaps an even easier alternative for achieving curving walls is to use a dense foam sheet such as Plastazote, which is spongy and very flexible, or a thin styrene plastic (see below).

I have to say that I have mixed feelings about the use of foamboard for these models. On the one hand a good, robust, polyurethane-core foamboard is invaluable as a lightweight baseboard .. but if a cheap polystyrene-core one is used it is liable to warp badly over time and ends up showing every finger impression! This is also the problem when using foamboard for wall construction. It has to be handled very carefully, and unless one has taken the trouble to practise with the material for a while before trying to cut clean edges or door/window openings .. it just doesn’t look good! It’s true that it can be a massive time-saver in terms of representing appropriate wall thicknesses, as mentioned earlier. I would suggest you use it sparingly until you’ve mastered how to achieve perfectly clean, straight cuts.

White mountboard

It is essential to have white mountboard (or equivalent white card between 1-2mm thick) i.e white on both sides rather than white/black. Otherwise, the model can become chequered with distracting areas of black. In any case white mountboard tends to be cheaper and some brands are softer to cut. As with foamboard there are many similar brands of white card with a standard mountboard thickness (c. 1.4mm, or 1400microns as it’s sometimes written) and these will vary greatly in hardness and quality. Matte is definitely better to choose (there are some semi-glossy types), and avoid white card which has a noticeable layering inside (a bit like plywood) because this is likely to be the toughest to cut! The same is true generally of ‘greyboard’ or recycled grey or brown cardboard which is hard and full of gritty particles.  Most of the softer forms, such as the standard Daler-Rowney mountboard sold in A1 size sheets are fine for perhaps most of the work ..walls or simple cut-outs.. but unsuitable for more delicate structures such as railings for example, because they are too thick in scale and will break apart if cut too thin.

Cutting
As a general rule when cutting anything by hand with a knife it is always better to take things carefully and slowly. There is never any advantage in being able to cut right through in one go even if that is relatively easy. A straighter, more right-angled and
cleaner cut is almost always achieved by starting carefully with a very light guiding cut and following through a few times, increasing the pressure gradually. As with all straight cutting, it should be done against a flat metal ruler (non-slip, or with masking tape along
the underside to make it so) and positioned so that the main light source is falling into the cutting edge, so that the marked line is not obscured by shadow. It is surprising how many people who might in other respects be very able with their hands find it quite difficult to cut a straight, clean line. From my experience of witnessing people trying to cut a straight line (must be easily in the thousands by now!) I’ve come to the conclusion that the problem lies in not properly ‘feeling’ the straight edge of the ruler enough to stick with it. It may really be this simple! The best advice I can give (apart from the points above) is to spend a little time getting acquainted just with what it feels like to press the scalpel blade firmly against a metal edge and move along evenly. It may also help to say that the scalpel blade is ‘meant to’ bend a little with the pressure of being pushed against the ruler and that if it doesn’t its always liable to wander.

Gluing
White Pva glue is always the best and cleanest option when gluing almost anything porous, like cardboard. Strong Pva (a.k.a wood glue, such as ‘Evo-stik wood’) invariably gives stronger and cleaner joins and a good quality Pva can be surprisingly quick. When gluing edges the PVA must be used sparingly (and excess wiped off) for the quickest results on card. Especially if two larger pieces are being laminated (i.e. glued surface-to-surface) only spots of glue are needed to hold them firmly in place otherwise the water-based glue will cause warping if spread on too liberally.

If .. for whatever reasons of your own .. you prefer to use UHU, you must be able to control it! Unfortunately the UHU tube nozzle, the consistency of the glue and the way it comes out, are not designed for really precise control .. such as is needed when trying to apply the glue to a thin edge of card for example. Some practise is needed first. One tip is that if you want UHU to stick firmly more immediately .. almost as superglue does .. you have to apply the glue and position the piece down as you normally would, pressing firmly, but then lift it up again just a few millimetres. This will ‘string’ the glue slightly, and when you press the piece down again the bond will already be much firmer and will not need supporting.

Thinner white card

It is essential, if you want to keep in scale, to have recourse to something thinner than mountboard but still strong enough to stand up on its own if need be. It also helps if this card doesn’t fragment (divide into layers) so easily when finely cut. Usually the thin white card sold in art shops is not labelled by thickness but according to its weight per square metre. College shops in the UK tend to stock inexpensive thin white card from the art supply firm Seawhite in 200, 300 or 600gsm weights. The 300gsm is roughly 0.5mm thick and the 600gsm 1mm thick. These are quite strong, but also suitable for delicate cutting.

1:48 scale model for 'Boardwalk Empire' 2010

The 1/4 inch (1:48) scale white card model for ‘Boardwalk Empire’ not only fully clarified the space but also communicated much of the ‘look’ due to the inclusion of the signage. Courtesy HBO ‘Boardwalk Empire: Designing an Empire’.

Stencil card

This type of card is also known as ‘oiled manilla’ and is meant for making very fine-cut stencil shapes. The manilla card has been impregnated with linseed oil which prevents it from fraying or breaking so easily. This treatment also gives it a slightly waxy composition, making it easier to cut and ensuring a very sharp edge. Although it is by far the best for intricate work .. especially to convey repeated balusters, railings, delicate window frameworks etc .. it is not ideal for strictly ‘white card’ models because of its warm ochre colour. If used it needs to be covered, sprayed or painted .. unless the whole model becomes a similar colour! Although it contains oil it can be painted with water-based paints or glued using Pva quite easily. It will not warp as much as other types of card when painted. However, if it is used and needs to be made white I would recommend spraying it first with Simoniz white acrylic primer. This won’t eliminate all the colour, but most of it, and more importantly it will seal the surface so that once the primer is dry after a few hours, more water-based whitener such as white acrylic or gesso can be applied without the structures warping.

More about what’s achievable with oiled manilla can be found in Working with stencil card which is under ‘constructing’ in the Materials section.

Acetate

Thin acetate sheet is the most available clear plastic to use for representing window glass. At 1:50-1:20 scale this doesn’t need to be very thick and usually the slightly stiffer version of two commonly sold as A4/A3 sheets in graphics or copy shops (for writing or printing on to use for overhead projection) will remain flat enough.

Cutting
Acetate cuts easily with a scalpel but if need be thicker sheets can be scored and snapped cleanly. If scored lightly then bent on the score line it will stay together as corner, which is useful if trying to represent a glass construction without the messiness of having to glue edges. One can’t mark on acetate with a normal pencil so either the shape to be cut needs to be drawn on paper and used as a template underneath or the surface covered with masking tape and lines marked out on that.

Gluing
If gluing becomes necessary i.e. for attaching to the backs of window frames, small strips of double-sided tape are much cleaner than glue. Superglue for example will ‘fog’ acetate around the area glued while both the ‘cement’ intended for plastics and UHU tend to be difficult to control. A third alternative (but only if gluing acetate to another plastic such as styrene) is the thin plastic solvent available for melt-gluing a range of plastics (e.g. ‘Plastic Weld’ or ‘Extrufix’) which has to be brushed onto a joint from outside. This is generally much cleaner because any excess solvent will evaporate

Plastazote

This is a flexible foam (halfway between hard foam and ‘cushion’ foam) which is available in many thicknesses, densities and colours. Most people will be familiar with the similar, brightly coloured ‘hobbyfoam’ sheets for children which usually range between 1-3mm thickness. The material may also be familiar from exercise or camping mats. Although very soft it can be cut quite cleanly with a sharp scalpel though it can’t be sanded. At an appropriate thickness it can be ideal for curving walls for example, or even for building up a run of curving steps.

Gluing
Plastazote cannot be glued with Pva and even UHU may not be strong enough. A rubber contact adhesive such as ‘Evo-Stik Impact’ will be needed. This has to be lightly applied to both sides, left for a few minutes and then pressed together (UHU can sometimes be used as a contact adhesive in the same way). This has to be done carefully because there is no chance of repositioning. Some brands of this type of foam glue very readily with superglue.

Styrofoam, expanded polystyrene and PU foam

For some structures to be represented it’s easier and quicker to make solid blocks rather than having to construct boxes from a sheet material. Since white card models
don’t necessarily need to be permanent, these light, easily-worked, so-called ‘rigid’ foams may be an option. Styrofoam may be familiar as the light blue sheets (although styrofoam comes in other colours according to different grades or densities) made for wall insulation and commonly used in theatre and film workshops as a rapid carving material. Styrofoam is very finely-celled so it sands very well without crumbling .. using a sanding block it’s possible to get smooth, sharp-edged shapes fairly easily. But styrofoam is of particular benefit for achieving curved, streamlined or organic forms. Regular acrylic or acrylic gesso are best to use for painting it white, since spray paints will dissolve the surface. For more on how to shape styrofoam, including concave as well as convex forms, see my article Shaping styrofoam under ‘shaping’ in the Materials section.

Expanded polystyrene is basically the same substance but formed differently and the cells are much larger. This is made only in white and will be most familiar as hardware packaging material and ceiling tiles etc. This common ‘expanded polystyrene’ is often shortened to ‘EPS’ whereas styrofoam is officially ‘XPS’ meaning extruded polystyrene.

Polyurethane foam .. often referred to as ‘PU foam’ .. is usually found in white or beige, and is often a harder, denser rigid sheet foam than the others. It will resist the solvents in glues and spray-paints, though these will still work well to bond or cover it. Rigid PU foam is mainly available from suppliers of resins and fibreglass materials. But, nearer to home perhaps, some regular foamboards are made with a polyurethane core rather than polystyrene and the paper coverings are easy to peel off cleanly to use the smooth foam as a constructional or shaping material. Examples are Kapa-line foamboard and London Graphic Centre’s Premier Polyboard.

Cutting
These foams are very easy to cut with a knife (or hot wire cutter, except PU foam) and both styrofoam and PU foam can be sanded effortlessly to a smooth, sharp finish even for very small forms. This is not the case with polystyrene because of its much larger cell structure. These tend to break up or can’t be sanded down below a certain size. All can be cut on a band saw, but failing this the best way to ensure a straight cut right through is (as with thick foamboard) to start cutting half way through on one side, take the line round and complete from the other side. Neither a scalpel nor Stanley knife will go very deep so often a sharp penknife, fruit knife or serrated bread knife will serve better. The rough edge produced can easily be sanded smooth with coarse sandpaper on a sanding block.

Gluing
Whereas PU foam is not affected by solvents and can be glued quite effectively with UHU, contact adhesives or even superglue, styrofoam and polystyrene require special ‘foam friendly’ glues such as ‘UHU Por’ or solvent free (I recently found that Gorilla Glue will also work very well since it is polyurethane). Strong Pva wood glue should work with all though takes a lot longer to set. Often it is much easier to tack foam pieces together with double-sided tape which, if pressed together hard enough, will often hold just as well as gluing. Another form of glue which styrofoam seems to accept is spraymount, especially effective if sprayed lightly on both surfaces like a contact adhesive.

Foamed Pvc and styrene

Although foamed Pvc sheet is not so easily obtainable (at least not from art shops) it has excellent properties, being somewhat easier to cut than even some forms of card while remaining much more durable and resistant to warping. The thinnest gauge (1mm) is ideal for delicate cut-outs such as windows and railings. The best brand of foamed Pvc for this kind of work is ‘Palight’, which is one of the smoothest and softest to cut ( or the similar ‘Palfoam’ which is even softer and supposed to be cheaper). Usually the minimum quantity one can order is an 8x4ft sheet (1220x2440mm) which can be quickly delivered, but if one accepts this the price of 1mm or 2mm Palight can work out cheaper than most forms of cardboard. A good online source for ordering/delivery is Bay Plastics www.plasticstockist.com (the 1-2mm white foamed Pvc included in the online catalogue is the cheaper ‘Palfoam’ rather than Palight). Recently though the 4D modelshop in London have started stocking 1mm and 2mm Palight in small (300x600mm) pieces, ideal if you just want to try out a small amount first.

Another plastic, styrene, is also available in sheet form but much thinner (down to 0.25mm) and is also often more suitable than card for slender cut-outs but is denser and harder to cut than the foamed Pvc. Both will allow a certain amount of bending. They are both used extensively in architectural model-making in place of card or wood and are obtainable either from specialist model-making shops such as 4D modelshop or suppliers of plastics (such as Abplas in London).

Gluing
Superglue works very well on both plastics for a quick, strong bond but working with superglue is a practised art because there is no time for repositioning before the glue takes. An alternative when working with these plastics (also generally a much cleaner one) is to use a plastic solvent such as ‘Plastic Weld’. Different from the usual gluing process, the pieces to be glued have to be set up firmly in position first and the solvent is then brushed into the join. Only a little is needed, which is drawn into the joint by ‘capillary action’. There it melts the plastic surfaces and effectively fuses the two pieces
of plastic together. Any excess solvent outside the joint quickly evaporates resulting in a very clean joint. ‘Plastic Weld’ (as with other brands of dichloromethane solvent) works best on styrene plastics but in tests I found that it did work on the foamed Pvc though it took longer to set. If this doesn’t take, the ‘gluing from outside’ method will work just as easily with thin superglue.

For more information on working with Palight foamed Pvc together with illustrative examples click on ‘Palight’ brand foamed Pvc under ‘constructing’ in the Materials section.

I maintain an up-to-date record of the best or most convenient places to get these special materials in Updated sources/prices of specific materials which can be found in the Suppliers section.

Some of the principles of technical drawing simply illustrated – Part 1

Have a look at this drawing. This is ‘technically speaking’ a technical drawing .. but a naked one! It describes an exact three-dimensional form in just three views, just using lines to represent the visible edges.

Orthographic projection without scale

Technical drawing relies on a number of agreed assumptions: .. that all views are of the same object and only that object, but from different viewpoints and that all views are the same scale; that all visible edges are shown by a line and that we assume those edges progress away from us to form faces which are normally flat and at right-angles unless otherwise indicated elsewhere on the drawing; that there is no perspective used in the drawing. In other words our lines of ‘sight’ do not converge with distance but are parallel and perpendicular (at right-angles to) the face of the object shown; that wherever possible these views are ‘lined up’ with each other so that we can easily relate one to another, moving three-dimensionally in space, as it were, around the object and that most often the ground-plan view is placed at the bottom because it is the ‘basis’ from which all else is elevated.

If you had not read  the above and had never seen a technical drawing before you wouldn’t be able to read much with certainty from these shapes. But when one takes on these agreed assumptions .. known as conventions in technical drawing .. one can start to read it, deducing various things, albeit not with complete certainty yet.

For example, if the bottom view is the ground-plan view then the shape above it is most likely to be the front face because it’s the same length and it explains that the line we see dividing the bottom form is because the block extends upwards at that point. Because the shape to the right of the front view is lined up on the same ‘level’ we can assume we’ve turned on a horizontal axis so it’s a side view and it looks the right width if we compare this to what we see on the ground-plan. We can be certain that we are looking at the left-hand side because this is the only view that fits with the other information we’ve got. We’ve had to do a small amount of mental/spatial visualization to get this! As I’ve said, this drawing has been stripped of all the additions which are supposed to make it easier to read than a visual puzzle .. but nevertheless a certain amount of mental visualization is always needed.

simple orthographic layout

Of course it all becomes easier to interpret if this is added .. a simple 3D line drawing using perspective! Now we can see clearly that we were right about the ground-plan view and the front, although we still have to use our power of visualization a little for the side. Despite being undeniably helpful, perspectival views haven’t been common in technical drawings up to now. This is probably because they take too long to do and are somewhat outside the skills or motivation range of most draughtsmen. It may also come from the purist notion that technical drawings shouldn’t need them, or that it even goes against the rulebook of using a language devoted to strict parallel projection. But nowadays it’s so easy to create perspective views in programmes such as SketchUp and either print or trace them, with or without shading, onto the drawing if there is an available space to put them.

The first version shown above satisfies many of the fundamental strictures of a proper technical drawing .. but of course not all. The most important missing are scale and measurement. Here below is the same drawing .. now almost fully ‘clothed’. Now it is clear what size we are dealing with .. the scale used for the drawing is given in the block of information commonly termed the title block and in any case the measurements are also displayed. We could get all the measurements if we scaled up the drawing 10 times (the scale given is 1:10) but the inclusion of most (often not completely all) of the measurements is a recognised courtesy, so that the reader of the drawing doesn’t have to use the scale ruler for everything. It’s also possible that a drawing can distort during copying, whereas written measurements remain exact. Also, if the scale is there but no measurements given against any lines, how can you be certain that the drawing has been copied at 100%?

basic orthographic drawing with measurement info

These measurements are written in millimetres here, the most common practice for theatre in the UK and increasingly now .. thank goodness! .. in film and television. Notice how the longer, overall measurements are kept a little separate to make them easier to find and notice how heights and lengths are not needlessly repeated. Notice how these ‘clothes’ sit .. comfortably, with some breathing space. The structure itself is still very clear, because the measurement lines are thinner and spaced a little away from the edge of it. Because of this the beginning and end of each measurement line needs to be emphasized, hence the slight crosses. Notice also that the measurements are written to be read in just two directions, from bottom-top and left-right .. rather than circling like ants!

We now also have important written information .. the views are labelled to remove any remaining doubt and the title block has, as the name suggests, a title! The sheet is identified as ‘1 of 3’ and the version dated. All this, and sometimes more, is necessary to keep track of what might become a large batch of drawings within a single project.

But what is represented here is a very simple form which assumes no significant surface detail. I intended this playground ‘street furniture’ unit to be made of brick and chose the dimensions to conform to standard brick measurements, but I wanted a specific pattern. When the designer intends an appearance which directly affects the construction of it, this information must also be on the drawing. I also had to draw all visible sides first in scale just to work out how standard bricks could be laid in the pattern I wanted. This illustrates yet another fundamental .. that measured drawing is not just a final rendition after all design decisions have been made, but an important tool for working things out even in the early stages.

complete orthographic information

The drawing is now starting to look more typical of the densely packed set drawings you may have seen if you’ve had a chance to look at any from theatre, film or television. The perspective view has had to go, to make room for the two remaining elevations as they’re now called, and to avoid any possible confusion arising from ‘back’ or ‘front’, ‘left’ and ‘right’, these are given letters which correspond with clear indications of viewpoint arranged around the ground-plan. This is a more sensible method, because these pointers not only indicate the direction of view but also where the point or rather the plane of view is. The identification and linking of parts of the drawing by means of letters and symbols is known as coding.

Notice also how the measurement lines are now arranged .. overall measurement on the outside with more detailed divisions closer to the object. The line bordering the sheet may seem just a presentation nicety .. but it actually has a more serious purpose. When the drawing is copied it indicates that the whole drawing has been copied, i.e. with nothing missing at the edges.

So, in conclusion to this first part, the ‘principles’ I referred to in the title are firstly those general and often unspoken assumptions I listed at the beginning, plus the following which I’ve tried to illustrate in this article, namely:

.. that technical drawings need four qualities above all else: accuracy (both drawn and written measurements should be correct, precise and in the right place); clarity (both meaning and appearance should be clear and readable); consistency (the ‘language’ used should be used in the same way throughout); economy (the drawing should be uncluttered by needless repetition)

.. that the layout, the arrangement of views on the sheet, is fundamental to the understanding or ‘reading’ of what they mean

.. that technical drawing primarily involves common sense in the way three-dimensional structures are represented in line but that common sense alone is not enough to either create or to read them. The special language of conventions has been developed to assist and it is expected to be used. This reduces the amount of mental visualization we need to employ when trying to understand three-dimensional space from a two-dimensional drawing, but it will always involve some!

.. that there should be no room for misinterpretation, no ‘reading between the lines’. The reader of the drawing should not have to make guesses outside of the agreed ‘assumptions’ or conventions referred to.

.. that the object views themselves should be treated a lot like VIPs or ‘untouchables’ .. clearly defined, with everything else at a respectful distance

.. that technical drawing is not just the ‘final account’ where all the sums are checked but an important tool in developing the design

.. that at the very least the primary measurements should always be written even if the scale is clear and that this is not only a courtesy but also allows the reader to check the accuracy of the copy

.. that the drawing should include all important information that directly concerns the structural making of the object or anything in ‘relief’ but doesn’t usually include details of painted design or colour. It is also generally agreed that the designer’s responsibility is to convey what is seen but not necessarily how it will be made

So far though I’ve illustrated using a simple, solid object which doesn’t bear much resemblance to a theatre or film set .. we’ve dealt with a simple block from ‘without’ rather than a box from within. When something like this is the object of the drawing there are some major differences .. the layout usually has to be different, the ground-plan contains much more information, and there is often the need for sections in addition to elevations, a device we haven’t considered yet. These and other things will be featured in Part 2.

 

Does foamed PVC have a grain?

Although this question will not be of much value to most people, it is certainly of interest to those few .. like myself .. who work with this material. The answer is .. yes, it does .. and this has a significant bearing on how one can get the best out of it! I have to confess that even though I’ve been using it for years, I’ve never properly realised this until now. There’s hardly any visible indication and although I had noticed at times that cutting in one direction seemed slightly harder than another I didn’t attribute a cause. I’d always assumed that sheet plastics just don’t have a ‘grain’, or rather a directional difference, because of the way they’re made and this would be especially so with foamed materials. In all these years I’ve never noticed any reference to a ‘grain’ in any of the product information available .. until now.

I should point out that I’m going on the basis of the tests I’ve made with the brand I use, which is Palight and Palfoam foamed Pvc manufactured by Palram. But I’m assuming that the manufacturing process for foamed Pvc will differ very little between the various brands even though there is often a difference in hardness. After looking more closely at the manufacturer’s documents available for download, I found this tucked away in some notes entitled ‘Installation’:

‘Palight is manufactured as an extruded foam PVC product with a directional grain running the entire length of the sheet. This manufacturing process gives Palight greater flexural strength in the direction of the extrusion. The grain of the Palight should always be installed perpendicular to the fastening point.’

In other words if a thin strip is cut along the direction of the grain this will have more rigidity than the same strip cut at a right-angle to it or ‘against’ the grain .. just like wood! To test this, amongst other things, I first had to find a way of recognising the grain direction, because as I’ve said .. it’s hardly noticeable when looking at the surface or the cut edges! If you hold a piece of Palight up to the light (better still a light that’s glancing the surface) and look at it closely, then rotate the piece 90° and look again, you may just about discern a faint direction of surface texture in one of these views. Another test involves making an indented line with a metal point, such as an embossing tool, a nail or a compass. Along the grain progress will be fairly smooth and hardly make any sound, whereas against the grain there will be a higher, scratchy sound and the surface will resist a bit more. A third test just involves cutting a strip, and is perhaps more noticeable in the thicker versions of Palight. I tested with squares of 1mm, 2mm and 5mm Palight, cutting strips just 5mm wide, first along one edge of the square and then the other. I made sure to keep my exertion with the knife roughly the same, and I found that I consistently needed a couple more strokes to cut against the grain. These strips were also noticeably more bendable than those cut along the grain.

So, I’ve already implied the possible advantages of utilising the grain direction and I’m guessing that the following will apply to all thicknesses .. having tested 1mm, 2mm and 5mm with the same results.  Thin structures will be stronger if the grain follows their length, and they will also be easier to cut! If strips are intended to be bent, this will be easier if they’re cut at a right-angle to or ‘against’ the grain. Finally, and as I’ve illustrated in my page ‘Palight’ brand foamed Pvc under constructing in the Materials section, Palight can be scraped with sandpaper to simulate a wood-grain surface and this will be easier following the actual grain of the plastic. Pvc can also be embossed, ideally using a smooth-pointed embossing tool, and a slightly different quality of line is produced either with or against the grain. You’ll have to try it out, to see which you prefer.