Originally Posted by
sensei
Building and gluing to crash proof as suggested is a waste of time and only hinders the performance of an airplane IMO... We build to fly. The proper choice of airframe materials, adhesives, and a properly designed structure that includes proper bond lines is what is needed.
Personally I only use thin and medium CA on all my wood airframe structures including firewalls and landing gear blocks, I do use thin laminating epoxy on my sheeted foam wings and tail feathers though. There are many really great adhesives out there, most are much stronger than the materials that make up our airframes, so again bond lines are key.
Bob
I'm not sure it hiinders performance but it certainly can be overkill. And "less is more" as long as the bonding requirements are met. I like to use a variety of adhesives...each has its strengths and weaknesses...Hysol on firewalls around spar tubes, gear mounting blocks, basically anywhere there is repeat vibration and high stress...West Systems epoxy for finishing and laminating glass and CF and a lot of CA framing the bones as well as clear silicone to cushion and help secure wheel pants and the like. I like CA a lot but I don't use it around high stress, high vibration areas as I have seen it fail. If the fuel tank area is exposed wood I like to thin epoxy with isopropyl alcohol about 50/50 and fuel proof the area. And....all joints must be flush and clean! And I always keep a little JB Weld on hand for odd jobs. All of this takes time and patience and I have had to "walk away" more than once on a project...I find better results working with smaller batches of adhesive or confining it to a smaller area so I can control and clean along the way...even Hysol has a short pot once it is out of the tube when the ambient temp is 105F.
Oli, could you please add JB Weld to the test list.