I put on my first set of slot head Waverleys a few days ago and didn't appreciate how fragile those little screws are compared to regular Waverleys. Broke one off when I thought I was doing everything right. I broke a Gotoh screw a while back as well and have used the same technique on both and it worked great.
I masked off the screw hole with several layers of binding tape then used the dental burr shown below to ream out the screw. Started on slow speed with the Dremel to get a starting notch then increased the speed. Had a syringe of water handy to cool things and an air gun to blow away the filings. I had the Dremel on a foot switch. A small easy out helped clean out the fragments. The first was hollowed out and removed in fragments, the second started spinning when I was about halfway down and I got it out largely intact.
The holes were not enlarged enough to show and I filled it with a piece of wood and re-drilled.
These are the same dental burrs I use for inlay. They end cut and really worked slick for this difficult problem. Picture shows the setup on some scrap wood.
Terry
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