| It's not unusual to have to apply thread sealer in order to keep the saddles from creeping down. It's just the ticket until you have to adjust the saddles, then it can be tricky to loosen them.
Best way is to apply heat. Take the strings off first. Insert the correct size hex key into the saddle screw and then heat the key with a solderding iron. The heat will transfer through the hex key to the saddle screw. Then gripping the hex key with something other than your fingers (HOT!), ease the set screw. Don't force it - if it won't move fairly easily, it's probably not hot enough. Completely remove the set screw, wipe off the threads and let it cool. Rassemble and you will be able to adjust the saddles again.
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Instrument Technician, Toronto
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