Replacement Tuners for my 1976 Johnny Smith

[sgosnell]

When you install the screws, make sure the threads go into the original threads in the headstock. Don't try to force the screws into new wood. You should be able to feel when the threads are into the grooves by turning the screw counterclockwise until you feel it drop into place. But the holes in the headstock can still be too small, of course, and you can drill new pilot holes of the correct diameter. Just be absolutely certain that a larger pilot hole is needed. It's also possible that the new screws have a different thread than the original, which would force the new tones to try to cut new wood. If that's the case, new pilot holes will probably be necessary.

[nevershouldhavesoldit]

It's also possible that the new screws have a different thread than the original, which would force the new tones to try to cut new wood. If that's the case, new pilot holes will probably be necessary.

If the new screws have a different thread count and pitch but are anywhere close to the same root diameter as the originals, it’s not this simple. A pilot hole is sized to be a bit smaller than the screw’s root (the diameter of the screw without its threads). The thread count and pitch determine how much smaller the pilot should be than the root. Finer and more numerous threads per mm don’t bite as deeply into the wood as coarse threads, so the pilot hole is a bit larger than it is for coarse threads on the same size screw. And the pilot hole should be smaller in softer woods than in hardwood.

If you drill into the old hole, even with a smaller bit than would be used for a virgin build, you’ll remove some of the female thread cut by the original screws. This may not leave enough wood for the replacement screws to bite, and you won’t be able to secure them. Even if you don’t drill at all, the coarse female threads in the wood may not offer enough wood for finer threads to hold.

The best solution would be screws with the original thread dimensions but a larger head and root above the threads to hold the tuners securely without ripping up the threads in the wood. It may be impossible to find these off the shelf - I used to machine what I needed on my old South Bend lathe until we retired to an apartment and I lost my shop. Without screws that fit properly and match the finish on the tuners, the holes might better be filled and redrilled to the correct size for the dimensions and thread of the new screws.

If whatever you’re trying to screw onto something else doesn’t go easily and feel right while assembling, don’t force it. Find the problem and solve it.

[JazzNote]

When you install the screws, make sure the threads go into the original threads in the headstock. Don't try to force the screws into new wood. You should be able to feel when the threads are into the grooves by turning the screw counterclockwise until you feel it drop into place. But the holes in the headstock can still be too small, of course, and you can drill new pilot holes of the correct diameter. Just be absolutely certain that a larger pilot hole is needed. It's also possible that the new screws have a different thread than the original, which would force the new tones to try to cut new wood. If that's the case, new pilot holes will probably be necessary.

If the new screws have a different thread count and pitch but are anywhere close to the same root diameter as the originals, it’s not this simple. A pilot hole is sized to be a bit smaller than the screw’s root (the diameter of the screw without its threads). The thread count and pitch determine how much smaller the pilot should be than the root. Finer and more numerous threads per mm don’t bite as deeply into the wood as coarse threads, so the pilot hole is a bit larger than it is for coarse threads on the same size screw. And the pilot hole should be smaller in softer woods than in hardwood.

If you drill into the old hole, even with a smaller bit than would be used for a virgin build, you’ll remove some of the female thread cut by the original screws. This may not leave enough wood for the replacement screws to bite, and you won’t be able to secure them. Even if you don’t drill at all, the coarse female threads in the wood may not offer enough wood for finer threads to hold.

The best solution would be screws with the original thread dimensions but a larger head and root above the threads to hold the tuners securely without ripping up the threads in the wood. It may be impossible to find these off the shelf - I used to machine what I needed on my old South Bend lathe until we retired to an apartment and I lost my shop. Without screws that fit properly and match the finish on the tuners, the holes might better be filled and redrilled to the correct size for the dimensions and thread of the new screws.

If whatever you’re trying to screw onto something else doesn’t go easily and feel right while assembling, don’t force it. Find the problem and solve it.

Thanks guys, so i certainly was right in my decision to use the old screws :-). The were slightly thinner AND had different thread. I'm wondering if Gibson used the same screws for all Sealfast equipped guitars. But whatever, i still think a buyer could expect the Kluson provided replacement screws to be able to pass through the holes of the replacement tuners without having to use force.

[Cunamara]

There's the complicated way, and there's a simple way: use the old screws. Good choice.

[sgosnell]

If the new screws have a different thread count and pitch but are anywhere close to the same root diameter as the originals, it’s not this simple.

Yes, if the screws are the same diameter but different threads, you basically have two choices. You can use the old screws, or you can drill the hole a little bigger and do a partial fill with a little wood glue and toothpicks or similar, and rethread the hole. That's a common way to fix a boogered screw hole. But the OP said he couldn't force the new screws into the holes, indicating that the new screws have a thicker stem, and that a slightly larger pilot hole would likely work, allowing new threads to be cut into the holes. I've done all of the above at one time or another, but my preference is using the old screws, unless there is an ugly color mismatch or some other problem.

[wintermoon]

Try a little soap on the threads

[Russ C.]

The new Klusons have arrived :-)

Attachment 89439

ok, new here. Not sure I did this correctly. Most important, DO NOT USE THE SCREWS THAT COME WITH THE NEW TUNERS. THEY ARE OF INFERIOR QUALITY AND EASILY SHEER OFF. Use your original screws or find premium quality USA MADE screws.