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Or a little more if you don't have a ceramic heater sitting around.
Since racing planes often die early deaths, you can either shell out $400+ for pre-built composite planes, $150-200 for framed up planes (that are AMA 428 compatible), or you can build.
Epoxy is a wonderful building adhesive once you get it figured out. I highly recommend reading The Epoxy Book from [URL=http://www.systemthree.com/index.html]System Three Resins[/URL]. You will learn all about the chemical process and additives like thixotropic agents, fillers, etc. One of the cool things about System Three epoxy is that it uses one base resin in a 2 to 1 ratio to hardener, but you can mix hardeners to control the pot life of mixed material. This of course affects the thin film set time, and the curing time. While you can use additives to change the curing characteristics, one thing that definitely speeds up the process is heat.
I've gone to using slow curing hardeners because I hate to get caught with exotherming epoxy in the pot. The downside is that you have to wait a day or two before you can proceed. The easy way to speed up the epoxy without having to worry about melting foam cores, or other heat intolerant materials, is raise the ambient temperature. If you raise the temperature of your shop to 95 degrees, the epoxy will cure in much less time. Unfortunately, you'll probably need to leave the shop at that temperature unless you have no air-conditioning and you are used to it.
I've learned that many producers of composite airframes use a curing oven, often made of styrofoam, pink, or blue foam. I made a small test oven to try out my idea for a curing oven, and now I'm building a much larger curing oven that can be top loaded with up to a 60" x 26" piece, or even longer through the end.
Michael Luvara's threads on building composite planes have been popular, and I've been working on applying the info from his threads, along with knowledge gained from dissecting composite airplane remains. The oven should be a nice addition and help speed the process of building up, even if it's just putting 0.7 oz glass on an airframe.
The oven is in process and in this photo, the sides and bottom have been cut to size and glued together.
The plane in this photo is a Q-500 plane called The Smasher that will be available as an all molded composite at a very nice price in the reasonably near future.
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In this photo, the sides have been glued on and filletted with adhesive. This is where the parts to be cured go. The strips on top are scraps cut off of the 1" pink foam. They are secured with 1 1/2" electro galvanized nails used like building pins.
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This where the ceramic heater, fan, and aluminum flashing material used for routing airflow will be. A hatch will allow easy access for adjusting the temperature on the heater without using a complicated thermometer setup.
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The bottom of The Smasher fuselage. Sure doesn't look like any Racer I've ever seen before.
This is #3 off the jig. Funny thing about jigs, the parts that come off of them often look identical, or very similar at the least. I can't build a straight fuselage with these kinds of compound curves without a good jig. So I'll be doing a "Building The Smasher" thread, too.
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The bolt on tail for The Smasher. Kevlar skin hinges, CF reinforced elevators, and jig built also. Don't you just love tangs on the tips?
A little more work and this Smasher will be ready for 0.7 oz glass and paint.
The curing oven has priority though, and I'll have more progress and pictures later today. Full plans and complete documentation will be available soon on [URL=http://www.pylonworld.com/]PylonWorld.com - The pylon racer's information source[/URL]. just check the [URL=http://www.pylonworld.com/news.htm]News page[/URL] for a station near you.
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Don Nice thread. I'm curious about your jigs (Fuse, and tail?)
This is #3 off the jig. Funny thing about jigs, the parts that come off of them often look identical, or very similar at the least. I can't build a straight fuselage with these kinds of compound curves without a good jig. So I'll be doing a "Building The Smasher" thread, too.
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Thanks Mike. I took some photos of the plane and the jigs and you can see them at [URL=http://www.rcuniverse.com/forum/tm.asp?m=240453]Building The Smasher[/URL]]
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Someone pointed out that epoxy fumes are hazardous from a couple of standpoints.
Some epoxies put off bad or toxic fumes that will be concentrated in a "Hot Box". Make sure you know the properties of the epoxy you are using before using a Hot Box such as the one in this thread.
Epoxy fumes may be flammable also. The selection of an appropriate heating device and heat control system is critical to prevent a possible hazard.
Before you build a Hot Box or Curing Oven, make sure you educate yourself on these and any other relevant topics.
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All Forums >> RC Airplanes >> Pylon Universe - RC Pylon Racing >> General Racing Discussion >> Build a curing oven for $50 
Build a curing oven for $50 - 
( and you other folks, too 
Warning -