Foam with Resin/Bondo

[ldefoor]

As every new person I have seen post here, we embark on this journey of creating a new life form. Really, that is what it feels like. I find myself struggling to decide which method to use, then it hits me. Why decide on a SPECIFIC method? Why not use both or have both at my disposal? Kind of a hybrid.

So, starting to look around I see some people have done this. One thing I read was a person putting bondo over top of the foam?

What do people thing of that?

 

[FlyinPhil]

Save yourself the heartache and woe of trying to put bondo on foam. Bondo is super brittle, and not very strong on its own. Pair that with a flexible base, and it is just going to crack and break away. I tried tossing bondo onto an eva foam magnum I was working on, and I ended up scrapping the project. It was extremely hard to sand flat due to it being flexible underneath, and it started cracking while I was trying to handle it and sand it smooth.

There is absolutely no need for bondo/filler on a foam build if you take your time making the armor pieces. Pep builds need bondo and smoothing because they are based on polygonal models with crisp edges. With foam, we can create a smooth, round, and contoured part to begin with, and skip all of that smoothing nonsense. Don't get me wrong, I love pepakura and believe it's the best way to create helmets (aside from 3d printing), I just personally don't believe that bondo and foam mix very well.

 

[Nim]

Just kinda thinking out loud here-
I'm not planning on using it at any time in the future, but what about using resin just to harden foam? Like what you'd do to a pep build before covering it in bondo. You'd probably run into the same issues, but if it was something that would be relatively stationary/inflexible might it do a decent job of stiffening the foam more than glue or plasti dip?

 

[Chernobyl]

Just kinda thinking out loud here-
I'm not planning on using it at any time in the future, but what about using resin just to harden foam? Like what you'd do to a pep build before covering it in bondo. You'd probably run into the same issues, but if it was something that would be relatively stationary/inflexible might it do a decent job of stiffening the foam more than glue or plasti dip?

I doubt it would work in the same way, honestly, and if you're going to work with fibreglass and resin, you may as well do it to a Pepakura form instead of a foam form.

 

[Burt]

Carpathia has done this.

http://www.405th.com/showthread.php?t=41518&p=702909&viewfull=1#post702909

 

[FlyinPhil]

Carpathia has done this.

http://www.405th.com/showthread.php?t=41518&p=702909&viewfull=1#post702909

That looks like a great way to finish foam!

But.... I would just use it in lieu of plasti dip as a finish, and I wouldn't try to bond over it. The pieces still remained fairly flexible, so bondo in thin layers would be veeeery likely to crack, and challenging to sand flat if it is layed on a bit thicker. I think this would be a great way to finish my foam weapons, though, and might have to give it a go.

Edit:

I just want to add this in as well.... one of my favorite things about foam armor is that it stays flexible, and is quite comfortable to wear. Hardening it defeats that attribute, though perhaps some people aren't quite as concerned about that as I am.

 

[Nim]

But.... I would just use it in lieu of plasti dip as a finish, and I wouldn't try to bond over it. The pieces still remained fairly flexible, so bondo in thin layers would be veeeery likely to crack, and challenging to sand flat if it is layed on a bit thicker. I think this would be a great way to finish my foam weapons, though, and might have to give it a go.

Edit:

I just want to add this in as well.... one of my favorite things about foam armor is that it stays flexible, and is quite comfortable to wear. Hardening it defeats that attribute, though perhaps some people aren't quite as concerned about that as I am.

I couldn't agree more. It was more of an idle curiosity of mine, as I'm happy with the rigidity of my armor as it is. I'm not sure what reasons someone would want to bondo over foam for as it seems more cost effective to just go with either foam or fiberglass, not to mention how easily it would get damaged.

Edit: Quote formatting was all wonky, fixed it.