RE: Hardened screw holes
 

PS. Nothing I lost was nearly as nice as the plane you lost though. Really too bad about that one. I still don't understand how we builders keep coming back for more. Makes me wonder what's wrong with us. I really want to be a part of a builder/flyer team. I know a great pilot who I would love to build for, but he already has a builder. Oh well... until I find someone I guess I just keep crashing my planes. :(

RE: Hardened screw holes
 

I don't think CA is fuel proof......

Jerry

RE: Hardened screw holes
 

TailSkid - It's not nitro-proof, but your engine shouldn't be spewing out raw fuel. CA is oil proof which is what gets all over your plane.

RE: Hardened screw holes
 

I think it's important to make sure your mounting block or plate is thick enough to get a good amount of threads in contact with the mounting screws. Also, one needs to be careful not to destroy newly-cut threads when tapping and cleaning out the hole with the tap, or the strength is compromised. I usually make a visual inspection of the tapped hole to check the threads.

To avoid nylon mounting screws from binding (once you have hardened the threaded hardwood with the CA and kicker, and allowed it to dry completely), I have use a small amount of paste wax rubbed on the screw threads as a lubricant. This makes for smooth threading of the screw, and helps prevent binding of the nylon, especially if you should apply a bit too much torque. The wax does not seem to weaken the threads, and seems to help repel oil which may creep onto the threaded block. I also recommend sealing the outside of the block or mounting plate with sealer or polyurethane (before applying the wax), to further insure against oil seeping into the wood and surrounding joint.

Regards,

Al Parry - "Eaglewatch"
[email protected]