John Bertotti
Jun-17-2004, 7:39pm
My older Vega needs a tuner tune up. What do I need to do? will Disassembling and cleaning them up help? They are almost to loose in part of the turn and way to tight in others. Are there any pieces that are routine wear that may need replaced? John http://www.mandolincafe.net/iB_html/non-cgi/emoticons/rock.gif
Bob DeVellis
Jun-18-2004, 12:58pm
John:
A cleaning and lubrication certainly can't hurt, but it might not help much either. It may simply be that the parts are worn. Something I've never done but keep saying I'll try the next time I get a vintage mandolin with a couple of bad tuners is swapping parts across strings. The A strings are often the ones with the bad tuners, due to the frequent need to retune those strings. I've thought that swapping the pinion gear with one from the other side of the headstock (like the G strings) might put a less-worn part where it's most needed. There's no reason why this shouldn't work, but I've never actually done it.
Sometimes, the pinion gear isn't seated properly on the shaft of the string post or isn't mated properly to the worm gear. The latter usually self-corrects when the tuner is turned but the former can persist and cause a gear to bind on part of its rotation. If it's been doing that for ages, it's probably worn unevenly. The plate that the moving parts are attached to can also get bent (e.g., the hook-like openings that the worm gear shaft sits in). That can cause binding, also. On headstocks without bushings, the hole the string post rides through in the peghead can become enlarged and the post can get yanked out of alignment a bit by the string force. Because the string post wants to tilt toward the tailpiece, the pinion gear attached to it is being forced out of alignnment with the worm gear. That will cause binding, also. But usually it's just excessive wear. Finding replacements to fit old instruments can be quite a challenge. So, unless it's really bad, it may be best just to do as much minor fiddling as you can to make things better. That would include a good cleaning and lubrication and possibly moving a pinion gear or two.