Has anyone used automotive vinyl over foam?

[sswift]

Hey guys,

I bought some cross linked polyethylene foam the other day from FoamByMail.com (it's like EVA foam mats but is smooth on both sides and comes in a variety of thicknesses), and I'd initially planned to paint it... But then I had the brilliant idea that I could avoid most of the sealing and sanding and painting by simply wrapping the stuff in adhesive backed stretchy heat-shrinkable automotive vinyl, and as a bonus the surface would never crack or chip and would be less likely to crease.

So I bought a bunch. Then I started looking for tutorials on how to best apply this stuff. And I found tons of them explaining how to apply it to vehicles, but next to nothing about applying it to foam armor! I spoke to one cosplayer who says he's used it and he suggested that it was necessary to use barge cement for everything.

I already bought a quart of barge to glue the edges of the foam together, but I don't relish the thought of trying to apply that to the whole surface of the armor and then trying to stretch the vinyl over it. And it kinda defeats the purpose of the vinyl, which was not only to reduce the amount of work required, but also to enable me to work indoors. I don't know how bad this barge stuff is gonna stink up the house yet. I bought what I hope is the blue can, so it won't be quite as aggressive as the yellow stuff that says its for industrial use.

Anyway, I was hoping to get a second opinion, and also an opinion on using 3M spray adhesive for foam (74 or 77) to attach the stuff, which would make it easier to achieve full and even coverage.

My original plan was to use a heat gun to stretch and adhere this stuff, and then use the barge to glue down the edges of the vinyl on the back side of the parts, but I don't want the vinyl pulling up as the parts flex, creating concave regions.

 

[George]

Hi S,

as an alternative or last resort,you could look into Cyehra's sealing method with a mixture of acrylic texture gel and woodglue.It's user and environment friendly,and afterwards you can paint it straight away with acrylic paints.Her tutorial: https://m.youtube.com/watch?v=StDwK-tKUuo
Less expensive and messy.I hope that helped.Sorry I cannot help you with your current method.

 

[WardWorks]

3m 77 will adhere the vinyl to the EVA foam. I created human sized DVD costumes a few years ago out of EVA foam. Vinyl graphics were printed and glued to the foam with 3m 77 and it held up to a fair amount of abuse.

I don't think you could get away with just gluing the edges of the vinyl. That will create ripples as the costume flexes. Continuous coverage would be best.

 

[sswift]

Automotive vinyl has an adhesive backing on it. The question is whether that adhesive alone is strong enough. That's why I'm looking for folks who have used this specific type of vinyl before. Of course, I'm going to test this myself once the stuff comes in, but that won't really tell me how it will hold up over the long run, and I'd like the costume to last.

 

[joberg]

Take a small sample of your vinyl and apply it to a small sample of your foam...test it IKEA style (you know, up and down movements, stretching, folding, etc) see the results, post the results

 

[SimplyTim]

https://youtu.be/k4wxf3RWBpU

https://youtu.be/3eZw5SZyIxU

Both are by a young guy/gal but show a good bit of the struggles and how to overcome. If and when you're decide to try something else, the video below using spandex as a cover is the method I'm intending for my current build.

https://youtu.be/_bMBvX40JTU

 

[sswift]

Well, I don't have the automotive vinyl or the barge cement in yet, but I can at least report that the cross linked polyethylene seems like it was an excellent choice! I don't know why anyone uses those EVA foam mats.

This is a 3" x 1/4" scrap piece I formed:



Note it's just the lighting that makes it appear the end is narrower than the middle on the bottom. The top was the edge cut with a hot knife at the factory and that had shrunk and melted a bit so that is actually a bit narrower. But the heat gun doesn't seem to shrink it normally.

 

[sswift]

Hey guys,

I got the automotive vinyl in today and I bought a can of 3M Super 77 adhesive spray and decided to do some testing!

My first test was to see how the vinyl would adhere to foam using just the adhesive on the back and a little heat.

Result: When cold, the vinyl barely adheres at all. It's just tacky enough to stick it in place, but it would fall off immediately otherwise. With heat applied, it's got a little more grab but it still peels all too easily from the foam, even after it is allowed to cool again. But applying heat shrinks the vinyl, which then causes the edges which aren't tacked down to wrinkle and pull up. If I used contact cement to tack the edges down before heating then perhaps I could avoid this, but I don't think I would end up with sharp corners, and where the vinyl bunches up when wrapping it around a curve it would be impossible to smooth out after the fact and the shrinkage wouldn't be enough to smooth it there.

My next test was to use 3M Super 77. I sprayed this onto the foam only, front and back, and let it set for 30 seconds until it was no longer super tacky. I then peeled it away from the newspaper I set it on and the newspaper came up with it. Oops. Hanging the piece by a string when spraying it may be a better option.

I then applied the vinyl over the foam and smoothed it out. I folded it around the corners and I was able to get pretty sharp corners. Curves still gave me problems though. And because the foam is flexible I can't heat stretch the vinyl easily to fit the form.



If I cut more slits in the foam around the corner it would have helped, but then there comes the question of how well I will be able to cover that up since both sides of the foam are visible on this part of the piece. Another option is to use my razor and cut the foam to fit the curve and then cut a smaller strip for the edge, and then have another back piece. I don't know yet how good those seams will look though. I could fold the foam over the edge from each side and then put a thin strip around the edge but I don't know if I will be able to see all the cuts where I went around the corner.

Anyway, the 3M Super 77 worked like a charm. The vinyl adhered tightly to the foam, even when it was folded around corners. I pulled a corner up here and you can see bits of foam still stuck the the vinyl:



I then used my heat gun to see its effect on the vinyl. Would it be able to shrink the vinyl I'd wrapped around that curved portion so make a nice smooth edge without many cuts?



Apparently not!

Also, rather than the heat gun making the vinyl super smooth and tight as a drum, it seems that the middle only ended up more wrinkled. But the corners became sharper, so it seems careful application of heat is required for the best results.

Now for the flex test. Would the vinyl pull away from the foam? Would it wrinkle or remain wrinkle free?



Ugh! This stuff isn't resilient against wrinkles at all!

I should note however that it is resilient to glue. I got some glue and newspaper on the front of it and I was able to scrape it off with my fingernail without much effect on the vinyl. So it has that going for it.

Okay, so it wrinkles. That's not good. I mean the armor is likely going to get folded and bent at some point, just putting it in the car, or sitting down. It would be nice if it didn't get tons of creases.

But as one final test I decided to hit it with the heat gun again:



Hey, not too shabby! And I just smoothed that out with my fingers.

Let's try creasing it again, but this time I'll smooth it out with a credit card...



Hmn... Well it still creases terribly when bending it 180 degrees, but it is certainly possible to repair the creases with the heat gun and some effort.

So what's the verdict here?

Well, the vinyl does hide small imperfections in the foam, including my crappy edge cuts. But it also creases easily. It's resilient though. It won't chip, and sticky glue can be scraped off without harming it much. I would imagine if there were some black rubber marks on it I could remove them with a scouring sponge. And if a sharp point scraped it it would probably fare better and show less damage than paint.

It's a bit of a pain in the ass to apply though. I wanted this to be less work, but in order to apply the vinyl I have to spray all the foam with 3M 77, and I need to do that outdoors. I guess I can bring the piece back inside after the tack wears off and apply the vinyl there though. As long as I'm not actively spraying inside, a fan in my window should be enough for any remaining fumes. I should also mention I only put a very light coat of this spray on the foam. One can of this stuff is going to cover the whole costume easily.

As of right now, I'm not sure if this is better or worse or more work than filling, sanding, sealing, and painting would be. I also don't know how resilient paint would be to my stress tests. I know some paint will crack. That's worse than creases I can repair with a heat gun I suppose.

The vinyl does make the part feel more like plastic. That's a plus. It's stiffer than those rubber coated foam squeeze toys, but still flexible.

Of course, I chose matte colors for my costume. That helps hide the creases. I'm actually using white for 90% of it so the creases will be less visible than the gray I used here specifically because it would be the worst case of the colors I have. But if you were to use a gloss for something like Iron Man, then creasing might be more of an issue for you.

Anyway, that's all for now I guess. I suppose I'll have to make do with the vinyl and hopefully it will work out for me on the final armor. I've only got two weeks to finish this before the convention. I'll post a photo of it when it's all done so you can see how it turned out!