---------------------------------------------------------- Glasair-List Digest Archive --- Total Messages Posted Tue 06/05/12: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:40 PM - Errata on tighting wing/fuse hardware (mppalmer@aol.com) 2. 08:29 PM - Re: Errata on tighting wing/fuse hardware (Craymondw@aol.com) ________________________________ Message 1 _____________________________________ Time: 07:40:03 PM PST US Subject: Glasair-List: Errata on tighting wing/fuse hardware From: mppalmer@aol.com I guess I wasn't clear. This was the second time I've re-torqued the hardware in the life of the plane. But you're correct - twice in 17 years isn't bad. The nuts are marked with nail polish. It's not a matter of the nuts backing out. It's a matter of the fiberglass changing dimension. It could be the high density foam crushing over time in addition to the resin shrinking. Yes, I can believe that the resin is constantly shrinking/curing. Someone told me once that, with the Glasairs, this is because the resin was never oven cured and so is constantly shrinking as it (still) cures. Remember how the factory started to oven cure the fiberglass gear legs on the FT's and TD's after a while? Taking them to a certain temperature in the oven made thema a lot stronger. Before they were oven cured, they used to creep outward. I know that here, in sunny, hot Phoenix, the dark red fairings on our Glasair have shrunk. You can see the texture of the weave of the cloth over time - kinda like the bones poking out in an emaciated person. And, consistent with oven curing, the engine mount to fuse bolts only needed to be re-torqued once. The heat of the engine compartment seems to have done a final cure and any further shrinkage there has been minimal. In any event, next time you're doing maintenance on the airplane, check for things like this. We tend to think the static parts stay static. But no harm in putting a wrench on them to make sure. Report your results here. It should be interesting to know what the rest of you find with attach hardware tightness on your plane. Mike <>< ________________________________ Message 2 _____________________________________ Time: 08:29:28 PM PST US From: Craymondw@aol.com Subject: Re: Glasair-List: Errata on tighting wing/fuse hardware Fiber glass pioneers like you will provide the data for future designs and maintenance and your knowledge will be incorporated into manuals. That German friend of mine informed me that the first German made fiber glass glider manufactured back in the late 1950's still flies!! 1950's resins, glass cloth and building techniques have evolved since then and there is no co mparison with today's products and technology. My German friend thinks over built Glasairs will be the D.C.3's of the future. After 21 years my fuselage skins are beginning to pull in a tiny bit and what was once a perfectly faired surface is beginning to look a little puckered in spots. From new, when I hangered my plane, I use a jack with a one foot by one foot board with a cushion of hard rubber foam and jack my wing up until the wheel comes off the ground, then I let the jack down completely and then jack it up about and inch or so to take the weight off the landing gear so that it doesn't splay out. Before I flew a Glasair I flew Grumman Tigers that had fiberglass legs and noticed the landing gear splayed out after a while and hoped to avoid that. I too mark all bolts and nuts with a line of red paint. When I saw that on my over hauled engine I thought it was a good idea. Too bad you are dropping out, I always took your advice. Chuck Raymond N16CD Gl2SFT 200HP In a message dated 6/5/2012 10:47:44 P.M. Eastern Daylight Time, mppalmer@aol.com writes: --> Glasair-List message posted by: mppalmer@aol.com I guess I wasn't clear. This was the second time I've re-torqued the hardware in the life of the plane. But you're correct - twice in 17 years isn't bad. The nuts are marked with nail polish. It's not a matter of the nuts backing out. It's a matter of the fiberglass changing dimension. It could be the high density foam crushing over time in addition to the resin shrinking. Yes, I can believe that the resin is constantly shrinking/curing. Someone told me once that, with the Glasairs, this is because the resin was never oven cured and so is constantly shrinking as it (still) cures. Remember how the factory started to oven cure the fiberglass gear legs on the FT's and TD's after a while? Taking them to a certain temperature in the oven made thema a lot stronger. Before they were oven cured, they used to creep outward. I know that here, in sunny, hot Phoenix, the dark red fairings on our Glasair have shrunk. You can see the texture of the weave of the cloth over time - kinda like the bones poking out in an emaciated person. And, consistent with oven curing, the engine mount to fuse bolts only needed to be re-torqued once. The heat of the engine compartment seems to have done a final cure and any further shrinkage there has been minimal. In any event, next time you're doing maintenance on the airplane, check for things like this. We tend to think the static parts stay static. But no harm in putting a wrench on them to make sure. Report your results here. It should be interesting to know what the rest of you find with attach hardware tightness on your plane. Mike <>< ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message glasair-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Glasair-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/glasair-list Browse Digests http://www.matronics.com/digest/glasair-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.