I have a decent W&B FBU that had some really bad horn scales and decided to use the matching scales froma recent ebay purchase. I was able to remove the pins and the domed washers and the bass stepped washers without too much difficulty. When I pinned the blade into the new scales, I used some bearing washers since the original didn't have any. It went together okay, but now it isn't tight enough to keep from opening and centering when closing. It will tighten some after tapping, but eventually works loose. Is it because of the bearing washers I put in? I can't tap them any tighter without risking cracking them. Any advice? I think I am going to have to re-pin them.