This follows on from An architectural model: Part 1 posted on January 12 where I outlined the purposes of the model, expanded a little on the use of foamed PVC for the build, and detailed my methods for achieving a convincing polished concrete effect. In this second part I am looking at the rest i.e. the ‘generalized’ treatment of the brick walls; my methods for staining the woodwork features; and lucky solutions re the baseboard and veneer cladding.
Staining the woodwork
The natural wood chosen by the architect for this project is oak. In Part 1 I explained that I was hoping to emphasize the model’s own sculptural presence, and it occurred to me at one point that a way of doing that would be to give the model its own material integrity, a ‘truth to materials’ in other words .. i.e. by using real oak, even real glass, and even real brick! But in practical terms this hardly ever accords with the functional remit, important in this case, of keeping to scale! So I couldn’t explore that direction at this time. On the question of real wood, there are only a few woods suited to fine-scale model work and fewer available in thin strips or sheets. Oak, because of its hardness and strong patterning, definitely isn’t one of them. So I’ve taken obeche and stained it to represent oak. I could also have chosen limewood ( ‘basswood’ in model shops ), which is even more precise to cut, but I wanted to take advantage of the slight patterning which shows up when obeche is stained. The woodwork features in the architect’s design were mostly related to the window structures so the following group of photos serves to show both (the windows will be dealt with in Part 3).
For this staining task I have used one of my favourite methods (suitable for both large or small work), which is to use a clear wax/oil based wood finish as a carrier, with a controlled amount of spirit-based stain mixed in ( it can’t be anything water-based ). I’ve found this much more successful than just using either a straight stain or a staining varnish partly because the wax/oil medium (along with anything added to it) penetrates the wood fibres more evenly, but also because it gives sufficient drying time to modify i.e. to rub away, or even out any excess. Spirit-based stains on their own can make woods like obeche or basswood too dark, unless they’re heavily thinned with white spirit. But then it’s difficult to control what appears once the wood dries out. I made tests using wax/oil varnish with different amounts of Colron ‘Medium Oak’ and there was little difference between the wet and dried results.
It was particularly important for me to make test samples here, because to reflect the distinctive tongue-and-groove cladding of the original I had to composit separately cut and sanded strips of obeche, otherwise there wouldn’t have been enough tonal difference between the strips. I was concerned though that staining might emphasize those lines in-between too much, but these turned out fine. On the left above I’ve just tried the wax/oil carrier on its own, and for the other two I added small amounts of Colron ‘Medium Oak’ Wood Dye. For those other two I also experimented with adding a little more colour variation using alcohol markers. I did this before the wax/oil was dry, though I think this could be done at any later stage. It shouldn’t be done before the wax/oil goes on though! .. I tried this with the same markers at the top of the middle sample piece. They came out much darker on the bare wood, whereas on the wax/oil the effect and strength is much easier to control.
The markers I used were from Spectrum Noir available as a pack of six ‘browns’. I’ve found that these generally have a much richer ink than Winsor & Newton Promarkers, as well as lasting longer and being cheaper in the first place!
The wax/oil medium I’ve used is from Osmo .. the photo above includes the tins I still have after more than 20 years and the wax/oil still works perfectly! I used Osmo products quite a lot when I was living in Germany, they were always available at Bauhaus (equivalent to our B&Q here). I used them not only to protect or colour wood, but also to seal or paint any similarly absorbent surface .. even plaster! In fact, it was a surprise but the Osmo treatment gave the cast plaster forms I was producing at the time the smoothest, best looking and most durable surface I could hope for! But Osmo ‘Wood Wax Finish’ (as it’s marketed in the UK) is intended for wood and comes either as clear, various whites, as a variety of wood stains, or in a small selection of basic colours.
On plaster as on wood, the first coat is likely to dry to a matt finish and a second coat is needed for a ‘satin’ sheen. Like any oil-based treatment the basic Osmo clear transparent will slightly darken any wood (though this is often not so noticeable with very light woods), and it also imparts a slightly yellow tinge (see further along for more on this). In the UK Osmo products have remained specialist, not stocked by any of the big DIY marts, so the best place to look for them is here
In this case there was every excuse to stylize, or rather generalize the brickwork exterior: it wasn’t an important visual part of the model’s function; I wanted to avoid slavish or fussy detail; and I wanted it to appear playful. There was also the fact that I’d really only had the architect’s plans as a guide in making the model, with just a few on-site photos available, so it was also a case of playing it safe. I wanted to emphasize the ‘warm and friendly’ in brick .. the ‘toy’ version of it, as I’d said, or as I imagined it might look mass-produced. I wanted to get a sense of textural richness and unifying pattern too, but time-wise to be able to get it relatively quickly! Embossing horizontal lines in 1mm foamed-Pvc was the quickest way I could think of to suggest the basic ingredient of a brickwork surface, and I’d done some texture tests with Rust-Oleum texture-spray for a previous project. The two effects just seemed to combine perfectly for what I wanted.
I used an embossing tool to score the lines in 1mm Palight. These are basically like scribing tools but with a rounded point instead of sharp ( in the UK, Poundland has them in their nail art section ). I had to try a few different orange or rust-red sprays to get an idea of the right direction for the base colour ( using red primers or leftover Montana cans ) before I could settle on the best .. MTN 94 Phoenix Orange. I left the sprayed pieces to fix more than day before going lightly over with Rust-Oleum ‘Pebble’ Stone Textured Finish. These Rust-Oleum sprays spit out tiny gobs and streaks in two colours at once and the effect is often better when subtle, but also I didn’t want to hide the base colour too much.
For the baseboard .. which is to be honest usually more hassle than enjoyment .. I was especially lucky that the smallest size of IKEA table-top suited the model perfectly! I’d strongly recommend these table-tops because they’re relatively light but suitably solid, in a variety of rectangular formats and a number of immaculate finishes including satin white, dark blue and beige. They also work out cheaper than ordering good quality MDF or plywood cut to size, plus if you pick up from store you can see what you’re getting. Incidentally, I like the idea of models having a certain size relationship with the human figure, just as pieces of furniture do. I feel that the small table-top format traditionally 4ft x 2ft average, now 1200 x 600, has a similar dimensional presence to a small person.
As I’d explained in Part 1 of this write-up, the ‘building blocks’ of the model were designed to be removable and I wanted to give them clear ‘footprints’ to lock into. This meant a raised surround with the shapes cut into it, not just a sprayed design on the floor. I was thinking here of the tactile experience of making objects connect, of feeling the joining more, rather than just sliding parts around. I cut the surround shape out of 2mm Palfoam (I’d waited to do this until I’d got all the room structures made, to make sure of a good fit). Instead of making each room as a box with the floor included I made them as open boxes to fit around floor shapes which became part of the base. I thought this was more interesting, as it gave the opportunity of revealing a more convincing ‘ground level plan’ underneath.
We’d gone through a few ideas for possible treatments of the surround, including a blotchy watercolourist abstract suggesting tree and shrub shapes seen from above. But from later building site photos it was unclear to me how many trees and shrubs would actually be remaining, and in any case I was running out of time .. so after thinking about a variety of quick surfacing options which would never have survived, I chose oak veneer because it was sympathetic and felt appropriate.
For the least possible hassle I wanted a veneer which was self-adhesive, also the best choice when cladding Palfoam. I’ve used these before and I’d recommend getting them from The Wood Veneer Hub because I think the prices compare well and delivery has always been quick. With veneers there aren’t usually many size options, for the 60cm width I required I had to get 2 metres, total cost around £45. The best way of organizing the sticking in this case was first trimming the veneer to a little over the length; laying it glue-side-up on a flat work surface; peeling off the backing paper; then carefully and slowly lowering the Palfoam surround shape onto it starting from one end. The thorough directions that came with the product recommended using what they call a ‘veneer scraper’ in other words a hard plastic smoothing blade with which to press down on the veneer strongly while sticking. I didn’t have one of these but I cut a rectangle in Palight, sanding the edge a little to prevent it from scratching. The adhesive is very strong but I think it pays to be thorough i.e. just smoothing it down with the hand or a cloth wouldn’t be enough.
Once this was done I could turn it over, place on a large cutting mat and trim the edges with a scalpel. Oak is a hard wood but the veneer is extra thin, so this wasn’t difficult. I’d made sure that I’d kept the backing paper so that I could put some back on the interior leftovers. Since I had trimmed the veneer from its underside, the final task was to smooth down all topside edges (120 grit sandpaper) because otherwise they would catch.
Wood veneer comes unfinished, that is, the wood surface may look beautiful and feel smooth but it will need protection from dust and dirt. Medium-tone woods like oak will quickly show darker finger-marks. So I knew that I would have to seal the wood surface but I really didn’t want it to go any darker. In the end I went a little the other way .. in the photo below I’ve laid a piece of untreated veneer over the final effect for comparison.
It’s vital to make test samples before using any type of wood treatment because sometimes the results are most unexpected! Here below for example, the first two tests on the left were Rustoleum Clear Sealer a matt water-based sealer I’ve used in the past on lighter woods such as ash or sycamore. On those it worked perfectly, the sealing coat was practically invisible with no change in colour or tone, but for some reason on the oak it couldn’t have been more different! As a second test, I diluted the sealer 1:1 with water, and this was different but still surprising. For the third on the right I tried Rustoleum Furniture Lacquer a matt spirit-based finish which is normally intended as a protective coating for chalk paint. This result was much more as I’d expected.
In the end I went for the Osmo Wood Wax Finish, mixing the clear version I had (No. 3101) with some transparent white (No. 3111). Below from the left is the straight clear, then the transparent white and lastly a 1:1 mix of the two which was the final choice. With any mix like this which contains some pigment it’s important to use a soft flat brush and to keep working the liquid into and over the surface to avoid any pigment pooling.
In the course of working on this base layer I successfully solved a problem which had troubled me for a long time. How can you place a large cut-out shape (such as the one above) into exactly the position you want it (with a nice 1cm margin all round in this case), making any slight adjustments that might be necessary, but then stick it down without moving it from that exact position? Of course I’d thought about pencilled corner guides, even little corner blocks, to fix the position for later when the glue-covered surface is impatiently waiting! That’s the whole problem .. anyone who’s tried to manoeuvre a large, bendy, sticky sheet into exactly the right position before any of it starts sticking anywhere it shouldn’t will know the problem!
I solved the problem, thanks partly to double-sided carpet tape. This is a good one .. ‘Rhino’ Double Sided Carpet Tape, from Ultratape .. I’ve used it for years and it’s often sold very cheaply for some reason. I knew that this kind of smooth, thin carpet tape would be fine for securing smooth Palfoam to a smooth, manufactured surface (in this case painted MDF). It just doesn’t usually hold that long on porous, dusty or uneven surfaces.
I hoped that I could take full advantage of the fact that the tape could be fully applied, as shown below, and then stripped of its non-stick covering, but in stages. Take note of the little square of tape that I’ve put in the bottom right corner.
Once the taping was done I turned the sheet over, positioned it on the baseboard exactly as I wanted it, but then put whatever weights I had near the far three corners leaving that corner with the square of tape free. I could then carefully bend that corner up a little just to get at the tape covering and pull it out with tweezers. Then I could press this corner firmly down. Now it’s stuck at one corner and all the other corners are still fine. Then it was a case of carefully repositioning weights so that enough of the sheet could be flexed to get at the end corners of tape lines, to pull out the covering strips .. progressing in this fashion roughly diagonally from where I started. Incidentally I had to use this photo taken to remind myself where I’d put the pieces of tape because they’re not all easy to see once the sticking starts.
In the final part to come I will be looking at the various options for making the windows in the model.