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HNNLIC
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Thats nice, but it appears like its only good for lip kits.
 

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Coops93 said:
where would you get the foam for that? i think i may be able to make a kit outa like kevlar at my school if i can just come up with the mould for it. good find on the site.
It's just big sheets of insulating foam from a DIY or builder's store. You want the pink or blue stuff, not the white bead foam.

Shaping the foam *is* coming up with the mold. He didn't explain the process very well on his site, but you're basically shaping the foam into the shape you want, covering it with a release agent (he used aluminium foil), and then modling the fiberglass over it and removing the foam afterwards. You could use this process to make any body kit part, not just front lips.

Kevlar would be really expensive, and probably a waste of money. I don't see how it would have any advantages over glass in an application like this.

In any case, my biggest concern would be to make it durable enough. Making a one-off product like that without vacuum-molding it is going to require a big thick coat of filler of some kind or another, and it'll probably crack up or flake off the first time you hit anything with it.
 

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HNNLIC
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How would we be able to use polyurethane for this instead of fiberglass?
 

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to use poly, you would need a negative mold, rather than a positive mold that the foam creates. The Poly, i think, needs to be sprayed in in some manner. Kevlar would prbobly not be all that usefull. While it would be stronger than the fiberglass, i think that you would still have similar problems with cracking as you would with fiberglass. I live in a hilly city, so fiberglass does not make sense, cause i would destroy it on parkinglots and such. But poly might be an option....
hmmm..... i think i have an idea, ill get back to some of you on DIY poly


Brian
 

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Blaque_Out said:
How would we be able to use polyurethane for this instead of fiberglass?
Make the positive mold out of foam, cast a glass part off it, and then build a frame around it to turn the glass part into a negative mold. Cast your poly parts off the "inside" of the negative mold. But I've never done any work with poly so I'm no expert on the rest of the process.

Even if I were going to do glass parts, I would use a negative mold. IMHO, assuming you took your time with the molds, it's a much better way to churn out high quality parts without vacuum bagging equipment. The "outside" of the finished product is then the part that was in contact with the mold - so, by creating a good mold surface, you're creating a good part surface without too much finishing effor or filler afterwards.

Why on earth I sold my vacuum setup years ago is beyond me. I could be making *so* many cool car parts. . . :oops:
 

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driver found said:
Shaping the foam *is* coming up with the mold. He didn't explain the process very well on his site, but you're basically shaping the foam into the shape you want, covering it with a release agent (he used aluminium foil), and then modling the fiberglass over it and removing the foam afterwards. You could use this process to make any body kit part, not just front lips.
Why would you take the foam out, wouldn't you just want to leave it on there?
It said on there that he put the foil so that the foam doesn't mess up with the fiberglass.
 

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I guess I just assumed he was using the aluminium foil as a release agent. I wouldn't want to leave the foam in place, and I don't see a reason why anyone else would.

And unless he's using some real quirky epoxy, I don't get what he meant by the statement about messing up the foam.

To each his own in the end I guess, but leaving a layer of aluminium foil and blucks of foam inside a molded part would certainly not be standard practice.
 

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b dash rian said:
some epoxy's will attack foams, i think thats why he suggested the foil
After years of molding composites using those same foam boards and the most common types of epoxy, I've never had a problem.
 

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HNNLIC
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driver found said:
b dash rian said:
some epoxy's will attack foams, i think thats why he suggested the foil
After years of molding composites using those same foam boards and the most common types of epoxy, I've never had a problem.
I know for a fact that clear liquid epoxy will eat up styrofoam. Its pretty interesting to watch as well. As far as other epoxies like the one used in fiberglassing, im not quite sure, but I'd assume they are stronger than a liquid epoxy.
 

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Blaque_Out said:
As far as other epoxies like the one used in fiberglassing, im not quite sure, but I'd assume they are stronger than a liquid epoxy.
Yes, Fiberglass resin will eat foam, at least the pink insulation foam from Home Depot. I used that same technique as that website to make a Viggen style rear spoiler a few weeks ago. It came out well but looks home made. That hardest part about making your own parts is carving the foam. It takes a long time to get it symmetrical and smooth enough so it doesn't look like crap.

Eric
 
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