aggie79 wrote:This is one of the most unique and intriguing approaches to building a teardrop that I've seen.
Obviously, this isn't your "first dance" with epoxy, composites, vacu-forming, etc. Other than the curves, do you think this approach is possible for a comparative newbie to fiberglass?
I'd say it would be good to approach this the same way I have - start small, with projects that don't really matter (i.e., cost) too much, then build up to making whatever you want. (afterthought - build fenders first - good way to gain experience and you'll have parts to sell if you do it right.)
I've done stitch-and-glue plywood/epoxy/fiberglass kayaks, vacuum molded various bits for them out of fiberglass and carbon over foam molds, and fabricated all sorts of other little bits, but this was my first step up to this scale. I was going to be all fancy with this first build, with a radiused transition to the roof, and even built a partial mold to test the concept, but in the end I ran myself out of time and went with square corners. Expedience rules!
I had been looking into vacuum resin infusion, but your method seems to be much better for what I may be doing on my second build. I don't mean to go off-track on your build, but would you mind commenting on vacuum pumps - particularly less expensive options than continuous-use commercial-grade pumps?
Get experience in traditional vacuum bagging first, then transition to infusion. If I were building these for resale I'd definitely go to infusion, as I think I could get a much better part finish without fairing labor, as well as more consistent parts. I would also thermoform the core if it weren't just for a one-off.
As for vacuum pumps - here's a short list of links to various suppliers and DIY options:
http://www.berkut13.com/sucker.htm
http://www.joewoodworker.com/veneering/ ... mpress.htm
http://www.dream-models.com/eco/vacuumpump.html
http://www.fiberglasssupply.com/Product ... gging.html
http://www.acp-composites.com/home.php?cat=4732
eBay search for: "AC vacuum", "refrigeration vacuum", etc. - here's a link I found:
http://cgi.ebay.com/Vintage-Robinair-2- ... 35ae40a5a4 (I own one of these that I paid even less for, but haven't hooked into an automated system yet. It's bulletproof and moves a LOT of air out of a bag FAST.)
If you decide to do the DIY route with the compressor let me suggest that your air outlet be run through a bronze wool oil trap into a homemade collection cup that's mounted to the vacuum inlet with a needle valve. If you do it right you'll have a self-recirculating open system that doesn't get oil all over the place.
For laminate materials, make sure you test what you're using before shooting a big part with it.
As a last word - don't underestimate the volume (and cost) of epoxy for a project of this size. I have a distributor next door, and was able to buy on-the-fly, but if I had to do it mail order I'd've been in trouble several times over.