Mold making and foam shaping

I want to make a old of my stock rear spoiler then I will be added some type of foam to it so I can shape it better and make it fit better then stock. Has anyone done this or could someone tell me what kind of products to use? I was just thinking of taking up my spoiler then doing a few layers of fiberglass. let it dry and pop it off and spray some foam that expands and then shape it and use filler to get the shape perfect. then make another mold this way i can make spoilers. . Also what kind of foam would be good?

This store is near me too, so maybe the guys that know can check it out and see.


tap plastic

anyone know of a good foam to shape?

I heard somewhere that that foam that they use to stick plastic flowers in is the stuff you need. You can get it at flower shops I guess. It's that green stuff. I don't recall the name of it, but I'll do some web searches to see what I can dig up.

Ah! Here we are. Floral Foam. http://www.save-on-crafts.com/wetwatholfoa.html

Here's an idea to get you started. http://www.alumilite.com/howto.cfm?ID=20

Now let me find the article in the magazine I read this in. I'll scan it for you. :ax

Cool thanks

Do u think they make that type of foam in a can? what I plan to do it make a cheap mold out of my rear spoiler. then fill that up with foam. then begin to shape it and make it good. then add body filler to smooth it out. then make a really good mold out of it. That flower foam though is perfect. I used some of that before to make a console ofr a friend. I wish I could find that stuff in cans or spray cans

[Lugnuts]

Originally Posted by f70t/a

Do u think they make that type of foam in a can? what I plan to do it make a cheap mold out of my rear spoiler. then fill that up with foam. then begin to shape it and make it good. then add body filler to smooth it out. then make a really good mold out of it. That flower foam though is perfect. I used some of that before to make a console ofr a friend. I wish I could find that stuff in cans or spray cans

what I use for this is the expandable urethane foam they sell at any hardware store. it comes in an aerosol can and once hard can be shaped. you can also get it in a can in liquid form but I am not sure were to get it maybe at a boat suply store.

when making your mold of the spoiler make sure you use a release agent. spray the spoiler down with the release than using fiber glass and a 2 part epoxy wet the fiber glass and apply it to the part. you should make it in two halfs so you can take it off the spoiler. also try to put some support bracing in the mold like plywood gussets to maintain the shape once removed and also it will help maintain the shape when you fill it with foam.

good idea. I will try that

Well I bought some foam today. here is my question. I will be making the mold today or tomorrow. what would be a good tool to shape the foam? I would like something that can flex so i can get into curves.

[Lugnuts]

Originally Posted by f70t/a

Well I bought some foam today. here is my question. I will be making the mold today or tomorrow. what would be a good tool to shape the foam? I would like something that can flex so i can get into curves.

a flexable file like a body rasp without the holder works good auto zone sells them. you can also use any kind of file or sandpaper to form it.

I went to homedepot and bought a sh*t load of files and stuff that could help me out

[Marty Phipps]

The biggest problem you're going to face with using foam for a "pattern" will be all the air holes in it
Make sure you use a fine coat of body filler on the final shape to seal the air pockets.
Ax made a very good point about the florist foam.
It's fairly dense, but also very soft.

Expanding urethane spray foam works well, plus it's not chemical reactive once cured.
meaning it wont disolve if you spray paint or primer on it

Ya once I got the shape I was gonna go body filler and make it perfect. then I plan to make a really good mold and start making rear spoilers for 70-73 birds that actually sit right and go with the body lines.