A ‘jungle temple’ wall in Kapa foam

After so many years I’m finally coming close to the ‘look’ for this piece that I originally wanted. I made this wall piece mainly for fun around eight years ago, and I’d looked forward to painting it, but when I first attempted it I was disappointed. There wasn’t any of the thrill I’d expected, and it failed to look convincing.

My painting abilities, or more especially my understanding of how to achieve ‘natural’ pattern or weathering, have moved on a bit over the last years. When I originally tried to paint this I didn’t do anything that much different to now .. a darkish basecoat allowed to dry, then other colours dry-brushed (or dry-sponged ) on top with progressively lighter tones. What was fundamentally different though, and why I failed, was because I hadn’t yet acknowledged what I’m calling the ‘chocolate trap’ .. by which I mean, how too much of a good thing nullifies the effect! The first portion I tried was a delight , seen on its own, so I couldn’t stop myself doing the same on every bit! I couldn’t understand why, once I had lavished attention on every portion and took a step back, the expected excitement just wasn’t there.

I’ve had a few more years now in which to start seeing what natural patterning really looks like i.e. how often the pattern is challenged, or broken. Here I’m including as ’natural’ the effects of natural processes on the artificial. We expect a stone, a brick or a cobble to age and wear down in much the same way as its neighbour, when in reality there can be many unplanned differences. More importantly, as humans our minds are conditioned to separate the pattern from the chaos .. it’s something we’ve been particularly good at .. but it does mean we can become blind to disturbances in the pattern especially when it comes to aesthetics. So my being too regular was not entirely my fault! For some while now when I’ve been leading sessions on painting surfaces I’ve been encouraging people to deliberately interrupt, subvert or randomise small parts of their patterns. It’s really interesting how hard that’s been for people to bring themselves to do!

Another improvement to my painting method has been to at least try to record the colours used for future reference, even if I can’t account for how I’ve mixed them. Nowadays I can create a much more convincing ‘algal’ or mossy effect using an olive green as a basis. In fact I’ve found this to be the best basis colour for any type of greenery.

The only conscious reason I had for making this piece at the time was to illustrate the sort of things which could be done with these, above .. foam-impressing tools made from sliced portions of plastic cake decoration moulds. These flat, hard plastic moulds are not meant for pressing, rather they’re for filling, with mouldable icing or marzipan for example. It wouldn’t be possible to make much of an impression with them as they are, even in a soft foam such as Kapa-line. But cutting them into smaller sections and pressing them into narrow strips of foam just about worked because then the foam had somewhere to move.

Another method I used for the first time on this wall was making a specifically shaped strip of foam in order for it to be sliced into individual pieces, lined up at the top. Shaping the small pieces separately would have taken a huge amount of time, not to mention it being much harder to control the shape. See this method illustrated in more detail in my article Pressing decoration into foam, shaping and wire- brushing under Special surfacing methods in the Methods section.

I remember wondering at the time how many other interesting shapes could be produced in this way .. slicing a shaped length into small portions. It reminded me of one of the most remarkable form-making ideas I’d ever seen. When I was living in Germany I saw some examples of simple animal figures carved in wood. There was nothing distinctive about the figures themselves .. just the way they were done, each as a small portion sliced from a lathe-turned ‘wheel’ shape. What was also really surprising was that this ingenious method was confined to a speck on the map, around a small town in south Germany called Seiffen. For many hundreds of years Seiffen had been a focus for wooden toy manufacture, and particularly for Christmas ornaments. The technique of lathe-turning a circular ‘mother’ form, known in German as Reifendrehen (translates as ‘tyre turning’) is thought to have started in Seiffen at the beginning of the 19th century and is still practiced there.

What was at first unclear to me was how the wood turner could possibly know how far to cut, just looking at the outside surface of the ‘tyre’ form, especially with a design as elaborate as the one below?

But a clue is provided in the following photo from the workshop of the museum in Seiffen. A wedge has been cut from the circular block while still on the lathe, and presumably at the beginning of working on it. I’m assuming that the design is drawn or pasted onto one of these interior faces as a guide, but which of course can only be checked once the lathe stops.

‘throw-sculpture’ May 2020


‘throw-sculpture’ n15, May 2020


‘throw-sculpture’ n28, May 2020


‘throw-sculpture’ n21, May 2020


‘throw-sculpture’ n23, May 2020


‘throw-sculpture’ n18, May 2020



I’ve written about this small object collection in the previous post, where I explained that creating ‘components’ which could be put together into bigger ensembles, different arrangements or loosely determined piles used to be one of my main ‘things’. I also referred to not being so keen on ‘deliberate arrangements’ nowadays, and that’s the basic idea behind these ‘throw-sculptures’, so I wanted to expand upon that idea now.

‘Nature isn’t always pretty’  Of course it’s not! So to re-phrase this, and because it’s not only about prettiness but more in this case about things being in the ‘right’ place .. ‘Nature isn’t always the thorough designer we’d like it to be’. For example, a beautifully balanced view of a lake seen through a framing of trees, fringed on the far side with forest and distant mountains beyond that, might have a Giant Hogweed sprouting up in centre view. Although it’s placement there would offend most people’s aesthetic, the Hogweed is probably much more ‘true to nature’ than the rest.

We’ve spent the ‘lifetime’ of our species rearranging nature according to our needs so we’re not only thoroughly conditioned by this approach to nature, it may even be in our genes by now, either way we may not be able to help ourselves. Is ‘love of nature’ or more importantly the respect needed to leave it be, no more than a continually resurfacing crumb of counter-culture?

When I’m teaching model-making and we come as a group to the painting of surfaces, one of the things I most enjoy advising (because it’s most often forgotten) is to include a little ‘mess’. Especially when creating a natural pattern, there’s the tendency to make it too regular. Anything other than an industrially produced pattern will have ‘messed up’ areas or slight distortions which we can easily spot if we scrutinise, but which do not corrupt the overall effect. In fact these aberrations are what makes a surface convincing .. they make it live .. because the eye takes them in as natural even if we are not directly aware of them.

So the arrangements above are just as they fell, and there were certainly ‘rogue’ elements I wanted to tweak but had to leave alone. It’s not just about allowing small disturbances though, it can also include seeing the value of a complete contravention, such as the Hogweed .. dissonance in music, an opposing notion .. except that there weren’t any of these here because of the way I’d shaped the pieces.

‘there’s no such thing as random’  Or again, rather .. there’s no such thing as ‘completely’ random, though some would argue there’s no such thing as anything being random at all. Although I conceived the piece to be dropped as a pile and these featured versions have been left as they landed without any adjustments, I did as I’ve said consciously create forms that were likely to settle in certain ways, to reflect the fact that ‘natural’ is always a combination of two types of occurrence ..  those which are already determined by previous actions and those which can’t be. So for example the forms are all straight, and smooth, and of the same basic shape .. they’re aesthetically determined anyway, so however oddly they fall they’ll be united. But in addition their shape determines how they will behave physically. So when I pick them up with both hands to drop them they can’t help but align, like a clutch of pencils. When dropped they slide over each other, one of them can’t balance easily on another, and there’s no way that any of them can land upright. After that, or rather after a whole list of other things like that, it’s anybody’s guess exactly how they’ll fall.

‘the artist shouldn’t decide everything’  In prepared ‘statements’ of artistic intention I think I used to put that I was not happy with the ‘Final Word’ presented in a gallery, unchangeable from that point on. I didn’t really think about the notion that each person will ‘change’ what they’re seeing anyway, regardless of what the artist does, according to their own internal version of the world. I didn’t consider either that what many artists do throughout their careers is basically reiterate the same sculpture or the same painting, so none can be construed as a ‘final word’ just the latest inflection of the same one. So Art can’t afford to be as pompous as I once thought it was, and that’s come as a relief .. and a release! However, that remains part of my explanation of why I’m interested in creating things which can be changed; played with; repurposed; individually customised etc.

Is this form of work accepted?  This was back in the 1990s, and in Germany, when I first tried these things .. and some people wanted them! But what I wasn’t prepared for was when people said, in honesty, that they’d prefer if I’d make my own arrangement, which they would then leave be! It defeated the object, or some of it .. and I was too, a bit. But so far I haven’t gathered much of an answer to the question. Should we assume that artists have a fuller understanding of their own work than others? Perhaps. Should we assume that artists are somehow better educated, stronger willed, or better at thinking than others? I don’t think so! Does the final artwork represent just one of many ways it could have gone and perhaps not necessarily the best? Hell yes!

Making ‘throw-sculptures’ and ‘smallhenges’ in wood and PVC, May-June 2020


David Neat 'throw-sculpture' sculptural object group 2020

‘throw-sculpture’ group1 2020


David Neat, 'men looking at stones', sculptural object group 2020

‘men looking at stones’ 2020


David Neat, 'pinehenge', sculptural object collection, 2020

‘woodhenge’ group 2020


David Neat, 'pinedolmens', sculptural object group, 2020

‘woodhenge with dolmens’ group 2020


David Neat 'polyvinylhenge', sculptural object group, 2020

‘polyvinylhenge’ group 2020



Almost as soon as we went into ‘hibernation’ here in the UK, I had the urge to work in wood. It seemed the natural thing to do in the situation! Perhaps it’s not surprising .. whittling wood can be very relaxing, especially if you’ve no firm objectives for the outcomes. I wanted something which could be progressed quite safely while listening to music, or audiobooks, or glancing at the TV, because I needed those distractions .. sometimes I needed to escape far away with them .. but the thought of achieving something constructive while escaping was pretty cool! I also had quite a bit of wood .. pine and ramin lengths, and birch from dismantled IKEA furniture .. which I thought I should get rid of, so it was also the positive thought of making something from nothing.

The ‘throw-sculpture’ group was the first, made from odd leftovers of ramin. This is a tough wood, not so tough for sensible mallet/chisel carving or using power tools, but tough enough when whittling with a scalpel which is what I’d insisted on using. The concept behind this artwork .. and the photo you’re seeing is just as much the ‘artwork’ as the group of wooden forms itself .. is one I’ve experimented with a number of times in different materials. Especially when I was living off my exhibited work for a certain time in Hamburg in the 1990’s I worked on collections of small forms which could be arranged differently each time, or thrown down part-randomly, or played with by the gallery audience. I tried to define them with various titles like ‘Variable Sculpture System’ or ‘Interactive Sculpture Kit’ but I wasn’t comfortable with any of them. At the time I didn’t know of any others who were doing, or had done, a similar thing, and that was probably just as well, because I’m impressionable like a chameleon, and if I’d had more contact with fellow artists I probably wouldn’t have been able to ‘see’ myself so clearly. The photo documents a ‘placed handsful’, meaning the 12 pieces of the group taken up with both hands and placed with not too much deliberation on a specially made mat of Douglas fir, with no alteration to the way they fall. This last condition was the most important part, because I’ve become very tired of ‘deliberate arrangements’. The pieces are shaped so that they will ‘organise’ themselves to a certain extent when dropped, but not quite according to our part-conditioned human aesthetic sense. In other words .. nature decides, to some extent.

‘men looking at stones’ developed as an offshoot from the ‘woodhenge’ work and the subject flowed naturally from that. It just ‘happened’ one day, because I cut the tip off a split end of wood and when placed on its feet it just seemed to say ‘Man’ very clearly! Nothing but filled trousers, if you like! So I made a number of them and this is the first ‘trial-photo composition’ featuring a pile of boulders I’d very painfully whittled from an old, hard and resinous length of pine, or maybe spruce. I’ve made a group of women now too, so there’ll be a series coming.

‘woodhenge’ was a bigger undertaking, or rather just much more of it, of which this test photo is just a fraction. Better photos will have to follow. I really regret not having kept an earlier version entitled ‘foamhenge’ which featured a number of standing ‘sarsens’ and a handful of ‘bluestones’ in untreated blue styrofoam. It just seemed very apt, including the stark ‘juxtapose’ of styrofoam being so fragile, ephemeral, synthetic and negatively ‘modern’. But the sanded, smoothed blue was also so beautiful in its own way. It’s almost gone now, the blue, because of EU regulations .. it was not benign apparently! So ‘woodhenge’ is more sustainable, and my purpose in whittling and smoothing quite a large collection of shapes and sizes, apart from justifying a huge load of television time, was an earlier idea I’d had for naturally-shaped building blocks. A more nature-inclined, less anthropocentric construction toy, so to speak!  No, with these you can’t build ambitious towers without them toppling fairly quickly! No, you can’t construct a tight, impervious wall, or a solid triumphal arch! What you can do with them though is appreciate how certain things balance in spite of their differences. What you can see is how even the smallest, most irregular element becomes a crucial part of the whole! There you go!

But you’ve noticed with ‘polyvinylhenge’ that my allegiances are muddled! I’ve been working with foamed PVC for so long, exploring and nurturing all that it’s capable of, that I’ve come to think of it as ‘mine’! It’s a plastic, which should not be considered lightly, but it’s such a wonderful, versatile plastic to work with! This was just a quickly thrown-together photo, and as I’ve said better are meant to follow, but the polyvinyl ‘stones’ are doing more or less what I wanted them to. It may be just visible that I’ve ‘grained’ the surfaces of the blocks by running sandpaper firmly along to give them a wood-like quality but I’m also looking at further subtle ‘pitting’ with blunt tools. The coloured PVC (this one is the grey, which is actually a very attractive one) is limited in thicknesses so for most of these forms I had to bond up to 6 cut-outs together before sanding.

Finally getting the hang of Instagram


I’ve been thinking about tackling Instagram for a while .. because I desperately needed more opportunity not to have to write that much .. if you can believe it!  But because I process photos quite ‘seriously’ on my PC before letting them loose, and because I have a Windows phone which I’m determined to keep until the bitter end .. there just didn’t seem much hope! But recently I did yet another search for alternative ways of uploading to Instagram, and finally I’ve found a way that works .. like a dream! It simply involves installing the free browser Vivaldi on the PC (no need to make it the default browser) and accessing Instagram through that! The extra piece of software doesn’t weigh the computer down like some other methods I’ve tried and failed with. The only drawback is that it only allows me to upload one photo at a time rather than grouped .. but this could change, and personally I prefer that anyway. Here’s the link where I found out about it ..


I’ll be posting on Instagram more regularly than here, I would imagine. WordPress will remain my serious ‘writing’ place, and I’ll be able to elaborate here especially regarding ‘instructional’ content but .. you might have noticed .. I seem to have less and less time to do that these days. Here are some images from the couple of posts I’ve put on Instagram so far .. and if you’re interested, have a look at



Above .. works in progress. Green styrofoam ‘beasts’ shaped in two halves, ready to be sealed to make moulds and casts from, and polyurethane resin cast ‘Arpish Dancers’ which I’m testing on a mock-lacquer sushi plate.

Below .. I recently ‘re-vamped’ some pen drawings from the Thames Foreshore made a few years ago, converting them into transparent ‘layers’, colouring them in Procreate and finishing them in PaintShop Pro. This is ‘Base#1-1’ and below is an enlarged detail from ‘Base#2-1’

Below .. resin cast ‘eggs’ and foamed-PVC ‘twigs’ collection. I’ve given the PVC my usual treatment of ‘graining’ with sandpaper and staining with Spectrum Noir alcohol ink pens, to resemble bone or wood. I’ve surfaced the mat underneath with a laminated digital sketch .. part of my experimentation with different presentations, or ‘contexts’ as I call them, for the ensembles of small sculptural forms.


Where to look for ready-made forms

I’ve compiled a new page List of sources for ready-made forms which I’ve put in the Materials section under ‘shaping’. If you’ve ever searched for something just the right size for puppet eyeballs, wondered whether you can get mini ‘taxidermy’ domes or whether there’s maybe a ‘magic’ way of making model bottles, you may appreciate this list and some of the tips included. I’ve copied the introduction and a short extract from the list here.

inside 4D modelshop, London

There are many instances where being able to take advantage of a pre-formed shape could not only save a lot of time but also opens up exciting possibilities .. promoting the work beyond one’s technical means. But often the thought of having to take the ‘time out’ to hunt down the right something is a dissuader, as is the notion that somehow using something ready-made is a bit of a cheat! I started this list originally to encourage myself to make more use of the ‘ready-made’ by having a quicker overview, but also because whenever I came across useful ‘things’ I never knew where to note them down for the future.

I’ve tried to divide the list into categories as far as possible, so here is the ‘Table of Contents’:

Discs especially small, in various materials; Domes flattened or semi-circular, whether thin/hollow or solid, including taller display domes; Spheres or balls whether hollow or solid; Ovals in 3D; Wheels and cogs; Teardrop shapes; Cones mainly solid; Straight dowels, rods, cylinders i.e. solid, circular in cross-section; Small rigid tube mainly plastics and metals; Larger round tubes including cardboard and plumbing supplies; Patterned rod or tubing because there are some; Curved or bendable rods, flexible tubing to include foams, Pvc and silicone, cable supplies; Rings; Trumpets, funnels etc; Eggs wooden or polystyrene; Blocks  ‘off the shelf’ and lastly Other forms for the rest.

Each section is organised by supplier and the underlined product titles are from the online catalogues so you can find them more easily in searches. The fact that this wording is sometimes specific and unpredictable is the reason why I’ve bothered to make a separate list in the first place .. after all, one could just do a Google search as/when needed .. but unless one uses many different search words some possibilities would always be missed! Prices were last updated in May 2016, all adjusted to include VAT. I haven’t just listed the cheapest, rather those suppliers who seem to offer the most useful range. If you have anything to add to the list your suggestions will be welcome!


Trumpets, funnels, ‘bottle’ shapes and superglue dosers

Heatshrink tubing or ‘sleeving’ is made from polyolefin plastic ( i.e. polyethylene, polypropylene ) and commonly used in electronics/electrics for wire insulation or bundling. It shrinks uniformly when heated with a heat gun, usually in the ratio 2:1 meaning it becomes half as small. It comes in different diameters and the clear versions are ideal for making small-scale ‘bottles’. Finer heatshrink tubing also makes very good ‘dosers’ for superglue work, to attach around the existing nozzle if more precision is needed (Poundland includes a few already in their packs of superglue bottles). I should note though that you will need a heat gun (preferably a small one) to shrink the tube uniformly as shown below.



Easi-Shrink’ Heatshrink Sleeving available in small diameters 1.2 – 6.4mm, and bigger sizes up to 100mm. 3.2mm diameter is ideal for 1:25 scale bottles (since these are commonly 8-9cm wide). Price for clear 3.2mm £0.83 per metre.

heat-shrink tubing


1ml or 3ml pipettes e.g £10.99 for 500 3ml pipettes

1ml and 3ml pipettes

I’ve included these because there are sections that can be cut to make reasonably good model bottles (from the thinner 1ml) or glasses depending on the scale you need. Bear in mind that this polyethylene plastic is never ‘glass’ clear, it has a slight frosting.


Plastic funnel set 50, 75, 100 and 120mm diameter £1.85

plastic funnel set


Plastic party glasses are a good source of shapes, but online suppliers don’t usually list measurements except capacity in ml.

Clear Brights Plastic Champagne Flutes’ 148ml (like image but clear, uncoloured) £4.14 pack of 10

plastic flutes


Cutting smooth holes in foam

I chanced upon this method of making almost perfect holes in rigid foam after I was asked about the best way to do the same in cake .. making holes to take tube supports between storeys of a wedding cake! For this I very roughly carved ‘teeth’ in the end of a plastic plumbing pipe, which as it turned out could be twisted into the cake without a problem. So I wondered whether something similar would work for other materials. I was fairly certain it stood a chance of working if I could cut the teeth finely enough, and for this a slightly harder form of PVC pipe is needed .. MuPVC ..which stands for ‘modified unplasticised polyvinyl chloride’.

I’ll need to cover this briefly first. The various plastic waste/drainage pipes you’ll see in any building supplier or DIY store (whether white, black, grey or brown) are likely to be two or more different plastic types. They will either be polypropylene (PP), ABS (a form of styrene), uPVC or MuPVC. MuPVC is harder than the others, but actually easier to cut or file cleanly because it is slightly more brittle. The only sure way of identifying it is finding the letters ‘MuPVC’ as part of the printed info along the side of the pipe, but also if the pipe is referred to by the store as ‘Solvent Weld’ it’s very likely to be MuPVC.

hole-cutting tools for rigid foam

Obviously there are only a few available diameters when it comes to these pipes and it depends on the store which ones they actually have. Standard outside diameters start at 22mm and normally end at around 44mm .. before they become something else, i.e. drainage or guttering pipes which are either brown or black. At the moment in the UK Wickes has the best selection of MuPVC .. 22mm, 36mm, 40mm and 50mm .. but don’t search for ‘mupvc’ in their online catalogue because that will only bring up one of them. Instead find the sub-section ‘Plastic pipe’ in ‘Heating & Plumbing’ which should show all the others, just described as ‘solvent weld’.

Wherever and whatever you find, the supplier normally should list the pipe according to its outside diameter, not its internal one. For more technical details see ..


squaring end of Pvc pipe

After trialling a few ways of making the ‘cutting’ edge, I found this to be the best method. Firstly, the end needs to be cut and filed/sanded straight i.e. at 90 degrees to the pipe length, as above. Then, using either sandpaper wrapped around a dowel or a round file, the thickness of the cut edge needs to be reduced to almost a point, as below. This should be a gradual slope (over 5-10mm) and on the inside .. the outside diameter remains constant.

chamfering end of Pvc pipe

The next job is to file the ‘teeth’ and I would recommend using a small-size power drill and a diamond-coated bit .. if you have those things. If not you have to do it by hand using a round needle file, but again, I’ve found the diamond-coated needle files more effective on hard plastics. The box of diamond-coated bits below is from Rolson, found in Maplin, costing around £5.00 as I remember.

fine filing tools

For each of the ‘teeth’ shown below I held the drill bit or file at a slant outwards from the centre of the ring and also slanting forwards around the ring, as saw teeth normally are. This may look painstaking, but it wasn’t really .. it look a while, but the plastic sanded comfortably. I made the teeth on the inside of the pipe so that the hole cut might be smoother.

finished 'teeth' on pipe

These tools worked well on the three types of rigid foam I work with .. blue styrofoam (extruded polystyrene); Kapa-line foamboard (polyurethane foam), and ‘Recticel’ another polyurethane insulation foam sold in thick sheets i.e. from Wickes.  Below, the pipe is first positioned on the foam and then turned very carefully until it has some purchase. After that it needs only moderate pressure while turning, making sure to keep the path of the tube straight .. the angled teeth will draw the tube in. Recticel is very soft and fibrous, but the tool still managed to make quite a smooth-sided hole.

turning foam 'hole cutter'

cutting holes in Recticel PU foam

I made use of the technique for the sculptural pieces I’m working on at the moment .. i.e. this prototype base shape for casting, which is meant to take a number of peg forms.

base unit shaped from styrofoam


Coating styrofoam with polyurethane resin

These are the latest forms I’ve been making for my .. not-quite-working-title .. Ridiculously Organic Construction Toy. For this I’ve been creating simulations of eroded rock and driftwood cast in resin, twisted Pvc branches covered in fake moss and lichen, corals, leaf clusters and strands of seaweed made from latex etc. But I also wanted to include some play elements which are more obviously scaled down, such as these brickwork ruin pieces. The best way of picturing the whole idea is to think of aquarium or reptile tank accessories and then imagine getting a large collection of these instead of a box of Lego. I’m still working on the question of how exactly the ‘construction’ is achieved .. i.e. how such components will be fixed together when playing .. but as part of the system I’m working on an artificial ‘mud’ which I’m hoping will solve part of it.

ruin fragments in resin-coated styrofoam

The forms above were cut/carved in regular blue styrofoam, textured using a heavy-duty wire brush and then coated in polyurethane resin. There’s a bit more to the ‘painting’ process .. something new I haven’t tried before .. but I’ll come to that. If properly done the method of resin coating makes the forms unbelievably strong! .. perhaps not enough to survive little children, but certainly any adult wear-and-tear.

Making a brickwork arch in styrofoam

These two photos illustrate other forms intended for the collection and the process of making them. I’ve described this method of form-making in more detail in Shaping styrofoam. The arch piece above started with a Pvc template, which I used to help sand a block shape. I found I had to make a separate drawing template (the one at the bottom) just in order to inscribe the brick pattern onto the styrofoam shape. Then I used the special diamond needle files pictured to scratch out the brickwork divisions at the right thickness. I wanted these pieces to be 1:12, i.e. usual dollshouse scale, but I’ll eventually use a mixture of scales.

Making a brickwork niche in styrofoam

To make the ruined ‘niche’ shapes above I also used the method I described in Shaping styrofoam of using a curved sander to create the concaves. I roughed out very deep channels for the mortar lines, because these will become partially filled with coloured resin .. and this is what gives the pieces unusual strength. I found it was better to make all the channels before attacking with the wire brush, because I made the pitted texture mainly by hitting or pressing with the brush. This peppers the foam with deep holes and it may fragment a bit too much if the channels are made afterwards.

diamond needle files

Here is a close-up of the type of file I’ve found to work best for detailing foam. These have a ‘diamond coated’ surface which has more of an effect on relatively soft materials than the other, cheaper, form of needle file which is just ‘toothed’, grooved metal.

wire brushes useful for texturing rigid foam

I usually use the smaller brushes pictured above when working with the more delicate polyurethane foam in Kapa-line foamboard, but styrofoam has a tougher surface .. the heavier wire brush has more effect. Importantly, the action in this case is not a brushing or sweeping one, it’s more hitting downwards and rocking around .. I call it ‘scumbling’.

styrofoam 'ruin' fragments

Now to get to the main point of this article! Of the polyurethane resins I most often use (Sika’s Biresin G26 and Tomps’ Fast Cast) I know that both can be used in the following way, but Tomps Fast Cast is best because it’s a little thinner, powder pigment mixes better into it, and according to Tomps it is designed to cure properly in very small amounts or in very thin layers. This is not the case with all polyurethane resins. I’m basically making a very quick-setting paint with it, and because it’s quick-setting it has to be done a little at a time. To dose both resin parts I use disposable plastic pipettes (which are available from a few places online) and usually work with not more than 2ml of each part at a time. I can normally manage to use up to 4ml before it thickens too much. Because there’s usually no time spare to clean the palette surface before it sets I use a ceramic tile which can be scraped clean afterwards. There’s always just enough time to clean the brush though, and this can be quickly done with acetone.

Coating styrofoam with polyurethane resin and pigment

Here I’ve dosed 1ml of each resin part together on the tile, added a small amount of powder pigment, mixed the whole together with a synthetic-hair paintbrush and used the same brush to paint the foam. Synthetic is best because the hairs will be rigid enough to push the pigmented resin into deep pattern, but full and fine enough to hold a lot of the paint. Powder pigment is the best form of colour to use .. strong colour, inexpensive, available .. and I usually find that it mixes better into resin than it does with water!

The polyurethane resin has no effect on styrofoam (unlike polyester resin), it will cure hard and ‘fused’ to the surface, and it’s done .. that is, it’s touch-hard and ready for further work .. in about 15 minutes! Whereas regular paint such as acrylic will infiltrate more and contract as it dries, polyurethane resin does less of both so there will be a little ‘smoothing over’ of fine surface detail. It will also be a gloss finish! .. which I don’t like, would never choose, and at the moment I’m experimenting with the different  ways of dealing with this. There is no matting additive for polyurethane resin, and regardless of which pigment or filler is mixed with it, the top surface exposed to the air will always be glossy. Obviously painting over with another matte paint, such as a good acrylic, is an option .. but polyurethane needs a lot of preparation if the paint coat is to resist a lot of handling and this is made difficult by such a patterned/textured surface.

One possible solution is to use my own version of cold powder coating. If you google ‘powder coating’ you will find that this refers to an industrial painting process in which fine thermoplastic powder is melted onto metal to create a durable surface. It’s very like the enamelling that you might have done at school, with coloured glass powder on a copper plate, melted in a small oven. My version does not require heat, and it’s perhaps more related to the model-making practice of scattering granules into glue to create a surface .. but it does share some of the surprising durability of these other methods!

crushed brick

Below is a close-up of the styrofoam ‘ruin’ forms after coating. I first gave the bare styrofoam an undercoating of resin mixed with black pigment, and then a second coat without any pigment, covering a small area at a time. While each portion was still wet I sprinkled a mix of finely crushed brick and sand onto the resin. I’m fortunate in that, living close to the Thames beach, I can pick up fragments of any colour of brick, illustrated above. Since these have already been broken down by the elements they are much easier to crush to a powder using mortar and pestle.

detail of brickwork surface done with 'powder coating' method

While working I could see that the particles were readily sinking into the thin coating of resin, and when the excess is shaken off after a few minutes the powdery top layer still adheres strongly. Polyurethane resin is a strong adhesive, especially if the dust or particles are porous and jagged. Having tested the strength of the surface once the resin cured I have little doubt that it is permanent. I still have to do some paint finishing on these pieces, emphasizing contrasts and colours and giving more ‘speckle’, but I have no worries about regular acrylic paint attaching itself on top. The greatest bonus in this particular case is that these pieces have a lot of the look and feel of real brick .. because that’s what it is!


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


More work with styrofoam

I’ve made some additions to my .. according to the statistical accounts .. most visited page Shaping Styrofoam which is under ‘Shaping’ in the Materials section. One is that epoxy resin glue works very well to bond it! I’d always assumed that epoxy would damage it, in the way polyester resin does .. but no, it doesn’t dissolve it and the bond is very strong! .. and I’ve used the cheapest stuff around, the one from Poundland! The other addition deals with preparing styrofoam prototypes for mouldmaking and I’m reproducing the entry here. I’m also finally managing, by the way, to hint more at what I’m up to at the moment .. working towards a solo exhibition of my current sculptural work which will take place in or around September next year!

If a styrofoam shape is being made as a prototype form intended for casting it doesn’t need to be made particularly durable .. it only needs to withstand silicone rubber being either brushed or poured over the surface. It does however need to be sealed, because if not the silicone rubber will grab into the surface too much and become very difficult to separate. Vaseline (petroleum jelly) is an ideal temporary sealant in this case because it can be easily brushed or rubbed into the micropores without damaging the surface. If care is taken not to use too much of it the Vaseline will also even out the surface, although I’ve noticed that most of it is absorbed into the silicone anyway. The only problem is .. it’s very difficult to see where you’re applying it! The solution is to colour it.

base unit shaped from styrofoam

This is one of many base-unit prototypes I’m making for a sculptural work which I can describe best by its working title .. ‘the ridiculously organic construction toy’! The components of the ‘nature driven’ form system will be assembled by means of holes and joining-plugs, hence all the holes in the base. Once I’ve made the mould from this the base units will be cast in polyurethane. I found a laughably easy way to carve out clean holes in styrofoam and I will explain this method sometime soon.

pigmented Vaseline

The best way to colour Vaseline is to first mix a little powder pigment, in this case half a teaspoonful, with roughly the same amount of Vaseline to make a thick paste not unlike tube oil paint. I chose the ultramarine here because it’s a strong pigment and finely ground, combining smoothly with the Vaseline .. some powder pigments may be grainy or clump a bit, which is not so good! The half teaspoonful was sufficient to give a strong colour to c. 50g of Vaseline when I added this to it, but one could use far less pigment. For example, the pigment will stain a porous prototype, so you have to bear this in mind if you want to keep it or if it’s an object of value.

using coloured Vaseline to seal styrofoam

There were a couple of larger scratches in the surface which I needed to fill and I’ve found that soft modelling wax (this one is the Terracotta Modelling Wax from Tiranti) is the easiest to use, worked carefully in with a brush.

filling larger holes with modelling wax

That’s actually it .. surprisingly short this time!

More on gluing, surfacing and repairing styrofoam

I’ve been slowly adding to my page on Shaping styrofoam in the Materials section, partly because I saw that it was one of the most visited pages. I wanted to consolidate the scraps of knowledge I’ve gained over the years on gluing styrofoam and the range of options for finishing or reinforcing the surface. I also wanted to look into a more satisfactory method of making repairs which I found, as you’ll see from the photos  .. well, very satisfying!

More on gluing styrofoam

I’ve bonded pieces of styrofoam together with a strong, double-sided carpet tape for years and they’re actually much more permanent than I’d first imagined. I have composite forms made many years ago which have been well-used as teaching examples and show no signs of coming apart! A few observations are necessary though! .. the two surfaces have to be smooth and flat against each other; if these surfaces have been sanded to make them fit, all dust should be removed, ideally vacuumed using a brush attachment. For the same reason the best bond occurs between the slightly ‘skinned’ surfaces of the sheet as it comes. When using the tape it’s particularly important to avoid placing it too near to where the styrofoam will be carved or sanded if one wants a seamless join .. but this applies almost equally when using most glues. But if it’s impossible to predict, or avoid, gluing in an area which will later be carved through or sanded, I’ve found some of the following options most suitable because they offer the least resistance.

For example what works surprisingly well as a bond between flat styrofoam sheets is spraymount, by which I mean the permanent spray-glue types from 3M. 3M’s ‘Craft Mount’, which is the strongest of their range, is particularly suited because it has a little more body. It should be sprayed on both sides to be joined (different to how it’s normally used), and it’s best to wait a little i.e. half a minute, before the two pieces are firmly pressed together. As with all contact glues, even the ‘instant’ ones, the bond will hold straight away but needs a day or two to get stronger. But the same applies with this as with double-sided tape .. the surfaces must be completely flat against each other and dust-free to bond strongly enough! Spraymount never sets completely hard, even though it’s grip is strong. When cutting through a glued edge the glue may catch the blade a bit but one can get used to this. It will sand reasonably well, especially if the tackiness gets mixed with styrofoam dust. For the same reason, I’ve found that it can help to dust the piece with talc while sanding.

If you want to glue pieces of styrofoam together which do not lie completely flat against each other .. you will need something ‘gap-filling’. There’s hardly anything more gap-filling and instant that hot-melt glue! Contrary to what you might have read elsewhere, hot-melt glue will work reasonably well with styrofoam .. as long as it’s not too hot! One just has to know how to manipulate it. Polystyrene foam is much more heat-sensitive than polyurethane foam .. it softens already at 90°C (193°F), while the temperature of hot-melt glue is around 180°C or more. So there is bound to be some melting of the styrofoam surface, but if you experiment and are careful you can find just the right number of seconds to wait before pressing the surfaces together, cooling the glue down a little but not so much that it fails to stick. Obviously it’s not possible to cover a whole surface, even a small one, with hot glue before most of it hardens. Think of this more like ‘riveting’ .. applying very quick spots of hot glue which will secure the pieces at those points once the glue has cooled. This method is definitely not for carving into or sanding though.

Another option is provided by the ever multi-tasking polyurethane! It’s common practice in scenic work and prop-building to use a rigid-setting, 2-part polyurethane foam to bond other foams such as styrofoam together. A small amount of the two parts must be mixed together in the directed ratio and then brushed quickly onto the joint before the foam pieces are pressed together. The resulting foam will expand to fill any gaps in the joint but the pieces must be held firmly in position while this is happening, otherwise they’ll be forced apart. Often this is easier said than done because the expanding foam exerts quite a force, but generally with these polyurethane foams and glues the less gap there is the stronger the joint will be. Prop-makers and sculptors are more likely to use the foams which are supplied in two separate parts and which need to be manually mixed .. a good source is a sculptor’s supplier such as Tiranti .. but the ‘instant foam’ tube cartridges sold for wall repairs or insulation are similar.

Gorilla glue is yet another option .. a polyurethane glue that comes as one part, so no mixing is necessary, and which foams while curing on contact with moisture. What this means is that both surfaces to be glued need a light misting first .. best with a small pump spray. The glue needs to be applied thinly to just one of the surfaces before the two pieces are pressed together. Below are two blocks of styrofoam already sprayed .. just enough to dampen the surface, certainly not dripping wet!

Gorilla Glue test, styrofoam moistened

Gorilla Glue can be deposited in spots if preferred, and these will spread once the pieces are squeezed together. It is not necessary to spread the glue beforehand over the whole surface but here I used a coffee stirrer just to distribute it better. What is very important to note (and not included in the manufacturer’s directions!) is that the glue should be dropped from the nozzle without letting it touch the wet surface! If it does moisture will contaminate the bottle and some of the glue will set inside .. as I found out when I tested it for the first time!

Gorilla Glue test, applying the glue

Below, I have weighted down the two pieces with a solid metal block. This was sufficient, although where possible it is always better to clamp the pieces together (sandwiched between flat pieces of wood to protect the styrofoam). The expansion occurs after a minute or so, 3-4 times in volume according to the manufacturer, and if the pieces are properly clamped the excess is forced outwards rather than upwards. If, because of the shape of the pieces, it is difficult to clamp without damaging the surface, masking tape or cling-film could be used to bind them together but these could give way a little and there may well some shifting as the foam expands. I had to correct the alignment of these blocks a few times before the foam stopped moving them.

Gorilla Glue test, weighting down

A couple of hours are needed for the glue to cure. Here below is a section through the seam line, cut with a knife then sanded. If it is properly cured the glue sands through well …. although it is different to the styrofoam it is much more alike than other glues. Also the bond is as strong as they say it is! I think polyurethane grabs on the styrofoam particularly well .. at least, I couldn’t pull the blocks apart.

Gorilla Glue test, section through the seam

More on surface treatments

If the surface is going to be reasonably protected .. I mean, if it’s not going to be handled and if it’s shielded from knocks etc. .. a good coat of acrylic paint may suffice. Acrylic paint will toughen the surface slightly, but by no means protect it from any handling, even if careful. Coating first with non-waterproof Pva glue and then painting will do a little more, and the same applies if coated with Pva or a water-based varnish afterwards. But the surface will still be very susceptible to scratches or dents.

If Paverpol is added to the paint mix .. more than half by volume .. greater surface strength can be achieved. Paverpol is a Pva-type medium manufactured in the US mainly for the hobby market and is intended for painting on fabrics or foams to give them a much tougher surface. For example fabric will become rigid and almost ‘resin-hard’ if soaked with it and the manufacturer recommends it for outdoor sculpture. It will not impart the same degree of toughness when painted on styrofoam because it doesn’t infiltrate far into the surface, but a couple of coats using Paverpol will be stronger than either regular Pva or acrylic alone. On its own Paverpol is quite viscous (a little more so than straight Pva glue usually is) but with careful brushing can be worked into a detailed surface without clogging it noticeably. In fact, whether applied straight or mixed with either powder pigment or acrylic paint for an opaque colour, the first coat will emphasise much of the porous foam surface and appear matt with an even roughness. If this is allowed to dry completely (needing a good few hours or preferably a whole day) and then painted again, the pores will start to be filled. Especially if combined with careful sanding between each coat using a medium grit sandpaper (for example 120-200 grit) a fairly smooth finish can be achieved. This must be applied as evenly as possible because raised streaks in the Paverpol will be tough to sand down!

Paverpol fabric strengthening medium

The next option is either painting or coating with a ‘polyfilla’. I make this distinction between ‘painting or coating’ because certain polyfillas can be thinned with water to a gesso-like consistency without losing too much of their strength and can be smoothly painted on. Polycell Fine Surface Polyfilla is in my experience the best of these. It is bought ready-made in tubs; it’s particularly smooth; thins evenly with water; sticks very well to sanded styrofoam and is far less subject to shrinking and cracking than other types. It also retains a little flexibility when dry. To get an even, lump-free cream with water it’s best to ‘condition’ some of it first either in a bowl with a spoon or on a clean glass plate with a spatula or palette knife. As you work it around it will become more liquid and if this is continued while adding water a few drops at a time you will gradually get something like the consistency of gesso, without any lumps.

The forms below were carved/sanded in styrofoam; the sanding stage finished with a flexible foam-backed sanding pad (see below) to achieve the smoothest surface. They were then painted with a thin coat of Polycell’s Fine Surface and left to dry for a day. After this a second coat was applied and then a third, which was left as before. The final treatment before painting was a careful sanding with a very coarse (60 grit) sandpaper which imparted a visible grain, softened with an overall rub using finer (240-300 grit) sanding cloth. The surface achieved with this polyfilla is not any tougher than the Paverpol, but it is much easier to sand, making it more ideal if the aim is an even, glass-smooth one. I painted these with Humbrol matt enamel, which is thin enough not to clog surface detail or add any additional texture but opaque enough for a rich and streak-free coverage.

Finished forms in styrofoam, coated in polyfilla, re-sanded and painted

I waited a few days for the paint to reach maximum hardness (although thin, the enamel dries very hard and durable) then rubbed carefully with a fine sanding sponge (these look similar to kitchen washing pads) to bring out some of the grain.

But an equally smooth and even harder surface can be achieved using a more specialized material. Casting resin is not usually considered as a medium for thin coating, mainly because it’s thought that it will fail to cure properly under a certain thickness. This may be true of some, but I’ve used both general-purpose (GP) polyester resin and special types of polyurethane resin many times for this, mixing in very small amounts and applied like a varnish .. with consistently good results! Polyester resin cannot be used to coat styrofoam because the styrene part of it will eat into the surface. However, polyester resin will work perfectly on polyurethane foam and, with predictable logic, polyurethane resin works perfectly on polystyrene foams such as styrofoam!

Uncoated and coated styrofoam 'heads'

The ‘head’ on the right above was painted with a small amount of Tomps Fast Cast polyurethane resin, first mixed together quickly and then worked with a soft brush into the styrofoam surface. I chose this brand because of its low viscosity, designed to cure even in very thin sections. After about an hour this cured enough to be sanded, just to even out the surface a little, before being coated again. More careful sanding followed, and finally one more coat. The overall coating is now akin to eggshell in thickness and hardness .. but in important respects stronger because it is supported uniformly by the rigid foam underneath. An ‘industrial’ ceramic-look smoothness can be achieved using a mixture of careful rubbing with special sanding ‘cloth’ (blue/green below) or thin layers cut from the surface of a nail parlour sanding block. These will flex with the shape, unlike sandpaper. Polyurethane resin sands surprisingly well for something so hard .. even easier to sand than some fillers!

Foam-backed and cloth-backed sanding materials

Below I’ve included the stages in the shaping of these ‘heads’ .. starting with a block shaped on a template, then sanding away from a centre line.

Stages in styrofoam shaping

The concaves for the eyes were started with a curved sanding tool, similar to the one used on the form at the beginning of Shaping styrofoam. These are easy to make, involving only a thin strip of sandpaper glued to a former.

Custom sanding tools for making concave shapes in foam

Major repairs or alterations to styrofoam forms

It is a long-established practice amongst carpenters and, in more recent times, restorers to neatly excise a damaged area .. i.e. to cut it neatly out .., glue a new block of the same material in its place, and then reshape this rather than ‘bodging’ with something else like a filler. Most fillers tend to shrink, to varying extent .. inevitable if they rely for hardening on the evaporation of a solvent. They usually can’t be laid on too thickly otherwise they can take an age to harden, and it may take a few goes to fill a deep repair properly. The other disadvantage of using fillers, especially to repair or alter styrofoam is that when set the filler material reacts very differently to sanding than the surrounding foam. It is usually much harder and inflexible, making a seamless transition difficult. The much better way to do it .. patching in with the same material .. is illustrated below.

This test form was made in the same way as one of the components described above .. first rough sanded and then finished with a 120 grit sanding block.

styrofoam repair demo test form

Below is some stylised ‘damage’ ..

styrofoam repair demo 'damaged' form

I sanded away a broad channel, making sure that the bottom of it was flat and smooth. The side edges are not parallel but a little tapered, so that a wedge-shaped block can be slid into position. This means that the block doesn’t need to be perfectly accurate in width.

styrofoam repair demo, damage cut out

In this case I secured the block with double-sided carpet tape. I’ve found Ultratape ‘Rhino’ very reliable so far. The block needs to be slid into position, as I’ve said, but not pressed down until it’s tight against the channel edges. I also slanted the edges of the block a little i.e. making the top surface a little bigger than the bottom, so that when pressed down it squeezes even more tightly into place. Styrofoam will compress a little to make this possible.

styrofoam repair demo 'patch' inserted

Then it was just a matter of re-attaching the semi-circular templates either end of the form (see earlier) to protect the undamaged surface and sanding the block down to the same point.

styrofoam repair demo 'sanded flush'

Just out of interest I tried similar repairs using Gorilla Glue as a filler ..thinking that, since the glue takes so well to the styrofoam and cures with a similar composition it might be an ideal solution. Unfortunately not!

Gorilla glue as filler, test piece

I made some notches with the scalpel, spray-moistened the styrofoam surface, then laid the glue into them making sure to spread it completely over the edges of the cuts. I also spray-moistened the topside of the glue after this was done.

Gorilla Glue as filler, cured foam

I waited a little more than two hours, during which the glue had expanded .. as the manufacturer says .. 3-4 times in volume. The first few millimetres of the cured foam was fine-pored and sandable, ideal in fact, but deeper down the bubbles were much bigger and the consistency soft and fibrous. It was like trying to sand bread! The foam had become weaker and more irregular because it was allowed to expand too much and I’m guessing that it would work better as a sandable filler if it were more confined i.e. by wrapping a non-stick covering over the form before the expansion starts.

Gorilla Glue as filler, sanded down