Quote:
Originally Posted by jimepting
...I know that fiberglas cloth/resin needs support to hold any shape while hardening. Therefore, it must be laid down over some sort of full support. I also know from personal experience that resin is not compatible with styrofoam. I have tried to mix it in syrofoam cups and it just disolves the cup. A while back I discussed this with someone in the ecomodding community who indicated that this problem could be sidestepped by painting the finished styrofoam shape with a water based latex paint before fiberglas overlayment. No direct experience, but I've heard it....
|
My vote is for foam/fiberglass.
For a method on how to do this, please look here....
http://ecomodder.com/forum/showthrea...els-10638.html
Last summer was spent making under body smoothing panels.
Using styrofoam, the steps are something like this:
1) Place hard mounts on the frame.
2) Start gluing bits and pieces of foam to the hard mounts.
3) Get the entire shape done with adequate support.
4) Remove the panel, and using epoxy resin, wet out the glass on the top side of the panel. This is the side that touches the car frame.
5) Place Saran wrap over any portions that touch the frame, then mount in the usual fashion. Think of Saran wrap as a peel-ply layer that keeps the wet resin from sticking anywhere it shouldn't.
6) Mount the panel back on the car and allow to setup.
7) Remove the panel and the Saran wrap and inspect. There still might be areas that stick and you will work carefully to get the area unstuck, with any thin objects that can be slid into position to break the glue bond.
8) Glass the other side of the panel, and place with the wetted area facing up, and let gravity do it's work.
9) There may occasions where you need to vacuum bag something, but if not done properly, the vacuum bagging process can distort the shape, and make a useless part.
The comment about resin and styrofoam not being compatible needs to be put into context. Polyester resin will attack styrofoam. It's the stinky stuff, and less costly.
Epoxy resin, such as West System will not attack styrofoam, and in fact is compatible with it. So is covering the styrofoam with Latex outside house paint first, then laying up the glass with Polyester resin. Just make sure all surfaces are covered with the paint first, or the Polyester resin will eat the foam.
You're correct in stating that fiberglass needs to be supported properly, for a good layup. The styrofoam itself actually works to make this happen. Assuming the foam board is thick enough for the task, laying the fiberglass cloth on the board and wetting the glass, will make a very good part, with hardly any flex during the hardening process.
You can use whatever you need to keep the panel in a neutral state while allowing the glass to setup and harden.
Hope this helps.
Jim.