Hi Arnie, I vote for heat too. In the worst case scenarios, I've pulled the letoff rail, clamped it in a bench vise, and quickly heated the regulating screw loops with a propane torch enough to melt a little candle wax in around the screw. It does pollute the rail, but it's a low expectation kind of performance requirement, unlike pinblocks or soundboards, and all you really need is for the screw to turn when you want it to, and not when you don't, and for the rail to stay where it's mounted. My preference in this kind of situation is to heat the rusty old screws as necessary (no wax), back them all the way out, and replace the screws and buttons with new ones. For what it's worth. Ron N
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