Space Marine Helmet - Need help with Plastidip!

I've been working on a Space Marine costume using Pepakura and 6mm craft foam. I've assembled the helmet using hot glue gun and filled the seams with Silicon Acrylic filler, also known as "Caulk". After repeatedly applying multiple layers of Caulk and sanding, I thought my helmet's surface was smooth ready for plastidip. However, after a couple coats from spraying plastidip, I realize the crevices still show as seen in the following pictures:





What should I have done to prevent his from happening to other parts of my costume and what can be done to fix my helmet?

I would say to get some Bondo on there, assuming it's compatible with the materials you've used so far.

Rubber Slug said:

I would say to get some Bondo on there, assuming it's compatible with the materials you've used so far.

Click to expand...

Interesting, I'll give it a shot. I'm not sure how well it will stick to plastidip or what happens if I sand plastidip. We'll see.

Great start on the helmet dude.

I haven't done it personally, but you probably want to stay away from using bondo (or any other non-flexible filler) on a flexible medium like foam. Even with plastidip over it, there's still flex to the foam, and that will cause the cured body filler to crack or lift.

Since you've already put plastidip on it I'm not sure if you could still use silicon caulk to fill in the areas, I'm not sure if something will inhibit curing or if it will be fine. I would try that on a test piece and see if that works out for you.

Also, in case you have to remake the helmet: try using super glue instead of hot glue to attach pieces of foam. Make neater cuts (a sharp blade will work wonders!). Don't be afraid to sand the foam and caulk to flatten out seams. And buy brush-on plastidip and brush it on like paint. You'll get far less of a stippling effect and you'll be get a more smooth result when it comes time to paint.