Gauging interest, 914-6 fiberglass engine tin Options

[Chris H.]

There are not many sources for a good racing style shroud and matching look surrounding tin. I think there would be a good market for the block off on top of a 964/993 3.6 shroud.

I have done a fair amount of composite work in my spare time.

If I could offer just a little advice to save you some time and hopefully improve your rate of success.

Anyone can wax up and slap some fiberglass into a mold. You will get a low quality part that, well, people will feel is worth less $. To create a much higher quality part, that is lighter, stronger, more stable dimensionally, and cosmetically more appealing, I would suggest the following:

1 - Consider using epoxy resin instead - Less smell around the house, better heat resistance of the final part, and less shrinkage or warping that can still happen days after you remove it from the mold. You also gain the ability to use other specialty cloth like kevlar or carbon fiber. Epoxy resin is more expensive versus regular vinyl ester resin. Epoxy Resin also comes in different ratios of hardener to resin. They have different applications, but check with your supplier for guidance. Also working with epoxy, one must be more careful with the measurement proportions when mixing. Too far off ratio in either direction can result in a failure. Think jello one way and really brittle on the other side of wrong mix. So suppliers might recommend a ratio pump, scale to weigh portions, or careful measurement cups, depending on how much of it you are doing.

2- Look into vacuum bagging. with a traditional hand layup process, you wax the mold or apply a release agent like PVA. Then you spray or apply your gelcoat or top layer of resin. Next, you wet out your cloth/mat and place into the mold. Then you roll out the air bubbles and ensure proper coverage. you must be careful to ensure the part thickness is even and that the cloth or mat to resin ratio is consistent. A part with too much resin and not enough of the reinforcing cloth or mat will be heavier than it needs to be for the same given strength.
But with vacuum bagging you follow the same process, but place the mold into a bag while the resin is still wet and draw a vacuum. This places a consistent pressure from the outside to hold the cloth in place from all directions, helps remove any trapped air bubbles, and (my favorite part) help remove excess resin which gets sucked out and into a reservoir before it can get to the pump.

I believe that with all the detailed bends in an engine shroud like that, vacuum bagging will improve how the mat lays down and stays in place for all those tight corners while the resin hardens.

Don't let the initial complexity or cost put you off. There are many DIY approaches out there that are yielding some excellent low cost results.

Here are some links to a good resource for vacuum bagging:
http://www.fibreglast.com/product/vacuum-b...Learning_Center

DIY approach - http://www.instructables.com/id/Vacuum-bagging-basics./

This is a supplier that i have used for materials with good success:
Fiberglass coatings https://www.fgci.com/


And please include some good personal protection in your budget. A good mask with replaceable filters designed for the chemicals you will be using, eye protection, and disposable gloves at a minimum. (IMG:style_emoticons/default/icon8.gif) That way you are around here for a long time to enjoy your new parts.

Happy mixing (IMG:style_emoticons/default/stirthepot.gif)

Sincerely
Chris

Very helpful info! Thank you!