I have some 4-40 screws that I have lock washers to hold a canopy. The washers are the type that have claws and penetrate the wood. The problem is the screws vibrate out. I put some thread lock on them but that stripped the lock washer out when I went to unscrew it. What is a good technique for securing?

You need to put a flat washer between the lock washer and the wood. I think that will help a lot.

Those "washers" are actually called "blind nuts". If you used the red locktite then you will never get them out as the red stuff is for more permanent type fixes. If you used the blue stuff then that is correct but you only need one little tiny drop. Much more than that and they will also act like red locktite. It's also important to use a little bit of CA glue on the side of the blind nut where the claws are and not on the threads so when the claw bites into the wood, the CA will help it stay there

In any case you can use rubber backed washers (bonded washers) I used to get mine from Microfasteners and since I started using them locktite has become a thing I only use for metal gear servos.

http://www.microfasteners.com/catalo...ts/WASFWRB.cfm

Use the #4 for 4-40 bolts

You can also make them, that's what I do now. Get a bunch of flat washers, find some thick rubber, like a door mat, rubber car mat, etc... that is around 1/16th inch thick and cut out some small pieces that are the same size as the washer. Glue the rubber to the washer and drill a hole slightly smaller than the screw or bolt. Now just stick the screw/bolt through the washer and tighten it down into the blind nut. The rubber gribs the surface and also the screw/bolt and it will not back out.

I got hold of a black rubber pickup truck mat about 3 months ago, bought 100 washers of each of the following sizes #4 for 4-40 stuff, #6 for 6-32 stuff, #8 for 8-32 stuff and #10 for 10-32 stuff.

To cut out the rubber I used a sanding drum on my dremel and did not put the sanding disk on the whole way, that way I used the edge of the disk to cut the circles and on the smaller washers, once I glued the rubber on I just trimmd the excess off. It's a bit of work but for 10 bucks for 400 washers and about a days worth of work I have plenty of each size

What Bubbagates said!!!

Ken

I'm curious is this canopy on a giant scale model?like was said here just flat washers with blue lock tight.

make washers out of fuel tubing works great

He said the washers had claws on them, I assumed he meant blind nuts

i was thinking those screws are rather big for a canopy is why i ask if it was a giant scale airplane.

I didn't notice that...hmmmm

Jigeye,
Do what Skiman said, although you godda give props to Bubba!! If you use about a good 1/4 inch of fuel tubing works like a charm on canopys and cowls. The reason some kind of rubber works so well it stops (for all intensive purposes) the vibration erosion. Know what I mean?