Alrighty, so I have finally uploaded some pics with some of the testing I've done in regards to foam and spandex.
I first started cutting out little hexagon pieces of 8mm foam, not the EVA foam but like a camping mat, which is pretty spongey and not very rigid:
That little square piece of paper I was to try get a hexagon template going, but it's extremely hard not to wreck it if you keep cutting in the middle of it with the x-acto knife. I decided to just freehand little hexagons, measuring around 1cm in width (which is the approximate length of hexagon on the undersuit, I believe anyway). Due to the foam's spongeyness, I found it was easier to cut holding the knive horizontally (like cutting steak) than it was vertically in the template I did. They weren't exactly shaped hexagons, but they did the job for the test I was trying to achieve.
For half of the hexagons, I cut them in half to make it approximately 4mm high, just to see if the depth of foam made a difference when stretching the foam around my body. I then glued all the hexagons in the pattern of the undersuit and attempted to space them 1mm apart from each other:
(Apologies for the glow, as I took the picture at night time)
It was difficult to know how much glue to use so the foam was adequately stuck onto the spandex and would hold properly. Definitely messy work and trying to keep the hexagons close yet still 1mm apart was a challenge as the glue made the spandex surface slippery. The glue was also causing the spandex to stuck to my art mat, so I had to keep moving it without disturbing the hexagon's position.
I then left the fabric on the washing line for the glue to cure (as per the foam glue's instructions) for 24 hours. It seemed to have worked! The glue definitely does provide enough give for the foam to remain stuck on the fabric. I did find that I used too much glue on the thicker 8mm foam bits than the 4mm foam bits, evident in the result shots below:
Thicker 8mm hex foam bits result
Thinner 4mm hex foam bits result
I've stretched the spandex piece around my thigh just to show how it looks with the foam pressing from underneath and the bumpiness I'm trying to achieve. As you can see, there is excess glue that has come through to the surface, but it was only a test piece to see if the glue would hold the foam to the fabric properly.
I think the thicker 8mm provides the bumpy texture a lot better than the 4mm pieces.
I don't have a photo of it, but I have submerged the test piece and the foam bits to see if the foam comes off. This was to simulate a drink spillage or similar. Thankfully, the foam remains glued to the fabric even though the glue is water soluble. I might try keeping it in water a little longer for further research but the signs appear that this method is fit for use.
Although it will be rather tedious and time consuming cutting out and gluing single hex foam pieces to the undersuit, I think the result will be quite rewarding. This in addition to sublimating the fabric with the rubber look (with the addition of scratches and weathering
THIS PATTERN that I created is what I'll probably print) I think I'll manage to have a breathable, lightweight undersuit that is still convincing rather than wearing actual furnace-inducing rubber. At the end of the day, I'll probably have little hexagon marks on my skin from the foam pressing in, but it'll be worth it
Let me know what people think and if you have any questions or want more pictures of the test piece.