Quote Originally Posted by efwd View Post
Ummm, is it concerning at all that there are a dozen holes drilled into the spar under the mount. Their right in the bottom side of the spar where all the stress is. Sure there are rivets to be placed through them but it seems to me rivets don't hold a piece together. Sure, they hold two parts together but they wont strengthen the spar just by filling a hole in it. What if I drilled a hole two inches away from the bracket, oops, then just put a rivet in to repair. No way right? Scratches, all retained under the bracket and filled with Hysol? Dang, its a tough one. If the bracket and Hysol maintain the integrity of the spar after all those holes then I am not sure it would not retain the scratches. Just me thinking.
Eddie
Your point has been expressed by many I've talked to recently. An experienced guy said that the hysol is packed in tight underneath the sleeve, esp. with the rivets. West systems epoxy even recommends 40 grit on aluminum when making a structural bond for the epoxy to key (of course after al prep, and al oxide pads). Also, I don't see any evidence that the scratches could make the joint any weaker. Originally I thought stress risers could emerge, but they could emerge just as easily from the holes given constant tension and compression under the spar. Dang is right. Wish I had some pictures of other's spars to compare to mine. Back to still thinking.