Does anyone rehab these tuners? Guitar is a '20s Weissenborn plectrum and they won't tighten. Screws through the ivoroid buttons are at max tightness. I bought another set and same situation. Isn't there supposed to be a leather washer to regulate tightness? I'm not a luthier and am mechanically hopeless and I've gone as far as I can go in terms of unscrewing, loosening and exploring (haven't found anything like a leather washer).
Here's an article by our host, Frank Ford, about banjo pegs. It's possible these things can't (or shouldn't) be repaired.
What does the inside look like?
Why not unscrew the knob and put a washer in there and see what happens? Between the knob and the housing.
Here (red arrow)? Tuner doesn't come apart completely (or I'm not willing to force things given my proven lack of mechanical competence) so it would have to be a split washer? How thick? What material?
The second set I bought has thin metal washers between the screw head and the top of the button, for whatever that's worth.
Looks like the only place, just try it with something. Maybe the screw will "bite" better - or not. The washer on top of the knob is there to distribute the load from the screw head over a bigger area.
Try contacting 'Bill Camp Banjos',experts on vintage banjo tuners.
The button does pull off, but often requires some force. Then a leather washer would be a good idea. Regardless, I'd replace the screw (most often a #4-36, likely to be a hard one to find) and lubricate the threads with oil or grease so it can be tightened more easily. Don't forget to grease the gears, too.
One way or the other, you'll want to increase the friction between the rotating post and the tin housing so you do need to get that screw tight.
At their best, these are among the worst geared banjo pegs, so don't feel alone in your frustration!
Thanks for the replies. I'll contact Bill Camp Banjos, as you suggest, Dave.
A quick and cheap way to deal with that might be to just grind a few threads off the screw, if it has in fact bottomed out. I'v done that on several cheap instrument tuners with good results. Feel free to disagree with me here anyone, if there's a reason that shouldn't be done. Adding washers sounds better to me, if you had some handy.