Endless Mountain Models http://www.scalesoaring.com email: [EMAIL PROTECTED]
don't make this more difficult than it has to be. Some ill advice out there it seems. You need to roughen up the area to be bonded inside the fuse. You do not need to sand so much you chew through the fibers. Secondly, there is rarely enough mold release or contaminants inside the fuselage of a molded fuse to degrade the joint, if in doubt clean with a de-greaser (prep sol or similar) or lacquer thinner before sanding. Do not use PFM or some temporary flexible glue on a retract, it will come loose. All 1-1 epoxy formulas are weaker and a lesser quality than 4:1 and or 5:1 commercial grade epoxies. The reason is 1:1 formulas incorporate volume fillers to make the mixing easier for consumers. Slower set epoxies regardless of mix ratios are notably stronger bonds than 5-15 minute formulas. If you use 1:1 hobby shop epoxy use 45-60 minute set time formulas with fumed silica thixotropic agent. The easiest (and best) method is to buy a quart size of West Systems or Fiberlay Pro Glas, or Aerospace Composites EZ Lam and use fumed silica as a thixotropic agent. 25 -45 minute cure formulas are fine with a good grade epoxy. This is not something that you won't use all the time if you are an active modeler, the shelf life is quite long and it is not so expensive considering what you get for your money in terms of quantity and quality. Never use glass bubbles except in fillets requiring easy sanding or non structural repairs. Glass bubbles add volume and weaken the cured epoxy. Fumed silica, AKA Cabosil, et al, does not add significant volume to the mix and will not degrade the final cure strength. Polyester resins are a thing of the past, emit waxy residue, and are unpredictable in the long run. If you are a hard lander, consider gluing in stringers from the retract bulkheads up to the wing rod or wing root plywood doublers if they exist. This will distribute the landing loads to the wing attachment points and will lessen the chance of breaking loose the retract. See my article on building a 1/3 Puchacz for pictures of all of the above examples. http://www.rcgroups.com/forums/showthread.php?t=141706&highlight=puchacz JD RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off.
