Harmony tuners

[Jessbusenitz]

I've been restoring a Harmony mandolin for an elderly lady who has had it for a long time but it was litterally falling apart. Anyway the tuners where missing some parts so I found some new replacements, but they get tight when I turn them one way and loose when turned the other way. I put some loc-tite on the screws that hold the gears down but still not working. Any suggestion? Jess:confused:

[fishtownmike]

Did you ream the holes. The shafts may be slightly to large for the holes and are binding when you turn each way causing the tightening and loosening. This can happen even with the originals. I have had originals bind making them difficult to turn. Reaming helps with this. ..Mike

[Jessbusenitz]

The post fit the holes fine, and they are old original harmony tuners. I'm thinking that the screws are tightening when I turn it clockwise and loose when counter cw.

[mandroid]

the screw in the center of the round gear? it's just there to hold the gear on the shaft.

Does it, the tuner machine mech, exhibit the same behavior off the instrument?

[Jessbusenitz]

Yeah even if the're off the mando they get tight.

[Paul Hostetter]

This sounds messy.

1) Using Loctite to hold the screws that hold the cogs on is pretty much uncalled for. Tensioning those screws properly is extremely important. How do you know you didn't overtighten those screws and then glue them that way?

2) The phenomenon of tuners seeming to tighten up as the string pitches are raised usually results from either a mismatch of post spacing, or mismatched cogs to worm gears.

Get better gears, and make sure the post spacing precisely matches the holes in the headstock. Repairing gears with missing parts is fairly risky. Just get a nice set of simple gears and put them on. If the worm is above the cog, which I suspect it is, consider these (http://www.stewmac.com/shop/Tuners/Mandolin_tuners/Golden_Age_A-style_Mandolin_Tuning_Machines.html).

You might want to consult my page on tuner maintenance (http://www.lutherie.net/tuner.maintenance.html), but I think you're wasting time on funky gears.

[Jessbusenitz]

I just got it finished, and tried to string it up and, it binds sometimes and sometimes not.I can't figure out why and when it decides to stick. I oiled everything, but that didn't seem to help. It dosn't have bushing but I don't think that would be the problem Are they a higher gear ratio? I think it's going to sit on the stand most of the time but I would like to get it playable.

[MikeEdgerton]

Post a picture of the tuners (the back of the headstock).

[Jessbusenitz]

I loosened the screws on the back a bunch (you could see a gap between the gear and baseplate ) and that seemed to help a little, but they still were very tight, but I was able to get it tuned :mandosmiley: ps. I have a picture but I'm not sure how to post them.