tatjna (tatjna) wrote,

Good things are happening in my corner of the world today

So you remember back ages ago I sent a bunch of pics of my Dad and his mate with their experimental SCUBA equipment back in the 1950s to the York Sub Aqua club, thinking they might like them? Well it turns out that the British Sub Aqua Club got their hands on them, and because the photos are kind of historic (as in, they depict the very first SCUBA apparatus being used), they have decided to use some of them on the cover of the 60th anniversary issue of SCUBA magazine.

My Dad, he was pretty cool. And he's still getting little snippets of fame, even posthumously. He would be pleased. ;-)

My samples of PVC expanded foam board (known as Palight here, Sintra in the US) arrived yesterday. This stuff is normally used for making signs, but it has thermal moulding properties which makes it of interest to me. It's $40 cheaper by the sheet than Wonderflex and the sheets are roughly twice the size. Thus, it's worth my while to investigate it for making armour with. So I emailed the manufacturers and they sent me three A4 sized sheets. Given that I'd asked for a 15 x 20cm sheet, I was stoked to get so much.

I had four tests in mind - curves, folds, darts, and joins. Doing these also allowed me to test things like how easy it is to cut, and free moulding. So anyway, I cut a bunch of bits from the first sheet for testing. A couple of them were using templates for the under-pauldrons because if I'm going to mess around I might as well be making progress at the same time, right?

Turns out you can draw on it in biro and cut it with a craft knife. Scissors would work but they are difficult on this 4mm thick stuff (they might be easier on the thinner sizes - it comes in 2mm and 3mm as well). The craft knife took 3-4 passes with a bit of kaha behind them, but once the first cut was made, the knife naturally followed the groove so it wasn't hard to stay on the line. I'm told you can also cut it with a coping saw. Anyway, then I started my experiments.


I applied the heat gun for maybe 20 seconds and I could see the surface of the material change a little bit. It was cool enough to pick up and only slightly flexible. I first tried bending it around a jar, but found that holding it and just using my fingers to form it worked better. It was easily cool enough to hold (not a heat conductor then). It started to set within 10 seconds and after 30ish seconds was stiff enough so I couldn't mould it any more.


For this I gave it a little longer with the heat gun and focused it on the centre, then used a ruler to fold it along a straight line. After 10 seconds it was holding the fold without support but I could still mould it if necessary.


I was really impressed with how it deals with darts. The way it maintains its rigidity while still being mouldable allows you to really get into that corner bit that can be troublesome when trying to make a smooth dart. And even though the sides didn't quite meet, the stiffness of the material holds the shape anyway so you could fill the gap with hot glue or modelling clay to smooth it out.

I wasn't really happy with the fold test because it hadn't come out as sharp as I'd hoped, so I tried another dart and this time scored along the back of the bit that would be folded, to try and create a sharp fold similar to those on Cullen's breastplate and leg armour.

This time my attempt to get the dart sides to join led to a bit of burning and curling of the edges of the plastic, but the fold is much sharper and I'm very happy with that result. Turns out it's very easy to shave the ridges from those curled-up edges with a craft knife, too.


This is two triangular bits joined together at roughly right angles. As you can see, heating it enough to melt and create a join tends to lead to wobbly curled edges. However, they are easy to shave off. Also, it occurs to me that it'd be pretty easy to form Wonderflex over a join like that and cover all manner of evils.

So then I thought I'd try something a bit harder - a curve and a fold with darts on the same piece:

This is the bit that goes around the corner of the shoulder on the under-pauldrons. I am very pleased with the way it came out, particularly the fact that it'll only take the addition of some smoothing clay to the join and it's 'done'.


-The biggest pro I think is that it retains some structural rigidity even when it's hot enough to mould. With Wonderflex, it gets hot and melty very quickly and becomes floppy, which makes it quite hard to do hand-moulding or reshaping without having a jig to place your piece on to keep the rest in shape while you work on one bit. With this stuff you can fiddle with one part and the rest will hold together while you do it.
- It's already thick enough to make convincing armour so I won't have to sandwich it with craft foam to get bulk.
- It's easily shaveable, carvable and cuttable even after being thermoformed.
- If you make a mistake you can just heat it up again and fix it.
- Won't need much prep before painting.
- Durable. I think I could stand on that pauldron bit and it'd be fine.


- Hard work to cut - I suspect I'll wreck a couple of craft knives per costume using it.
- Edges tend to curl if you heat it enough to stick to itself.
- Not really any lighter than Wonderflex.
- It's a bit fumey so air circulation will be important when working with it.

So the verdict is that I'm very excited about this stuff and will be getting a large sheet of it to use for the larger and stiffer parts of Cullen's armour and shield.

Other snippets of happycool things:

- We rented the house out. This means our financial stranglehold will end this week. Yay! I can get on with the things I've been putting off.
- Dr Wheel received two boxes in the mail yesterday, which are full of componentry and THINGS! Things which will make his art project!
- The YoT is out of his fire at will government bollocks 90 day trial period at his job. This means he now has actual employment rights!
- I redid the ring for Yorick and I like it a lot better now. All I need now is a good drying day and it'll be ready to bring for you on Friday, pombagira.

And it's only Wednesday! I got a call from my client with the sheep yesterday and she had been without power for a day at that point. Her sheep, her yards and the ground are all sopping. It'll take some special weather to dry them before the weekend, so we're trying for maybe Thursday night, then maybe Saturday. One day those sheep will get shorn!
Tags: experimenting with thermoplastics, fondle my armour baby, i make stuff, mmm plastic fumes
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