tiny screws

[arpthark]

I need one of these:





Any idea where to look? McMaster-Carr?

[LeMark]

What's the thread? Put the caliper on the threads

[arpthark]

What's the thread? Put the caliper on the threads

Unsure, can check tonight. How do you measure the thread with calipers?

[arpthark]

just post the diameter, there are charts that do the rest

[bloke]

If it's for that old Kruspe tuba, it's hard to know whether the threads are SAE or metric. Is the picture out of focus, or are some of the threads boogered?

[arpthark]

If it's for that old Kruspe tuba, it's hard to know whether the threads are SAE or metric. Is the picture out of focus, or are some of the threads boogered?

Yep, Kruspe. This is a screw for the string linkage on the backside of a valve lever.

Just a bit out of focus. This particular one is not boogered but another one of the same size is. Previous owner used some sort of nasty crud to glue the screw in place. I removed the glue and figured out they did that because the screw is loose. I checked the hole with another screw, and the female threads are OK, so it's just that one screw that is boogered, and not the threads inside the lever, thankfully.

[bort2.0]

Generally speaking, I've found that the screw thread/size/gauge/whatever is the important thing. You'll probably have to make compromises on the head style, and maybe even the length (but you can cut them down).

Get a good screw gauge and that'll help, as well as good sharp cutting tools.

Unless the original screws are really ornate or cool looking, it might be worth replacing all of them with the new ones, for a more uniform look.

Also, I wouldn't necessarily think the threads in the screw hole are perfect, and you may want to invest in some threading taps to either clean up what's there or to be able to fix things that are... um... boogered.

[bloke]

You can also pick up some SAE or metric French horn screws and tap the holes in the linkage to match the screws.

If you want squared-off style heads (ref: picture) VINTAGE King French horns (no longer made) featured screws styled in that manner.

possibly Olds...??

You could look through junk single horns and worn-out-valves doubles in the back of a repair shop...4

Otherwise, if you're perfectly fine with domed/brass, it's just a matter of determining the thread.

[arpthark]

This is a very tiny screw on the back of the tuba on the fourth valve lever that is almost completely obscured by tubing, and all the other ones work perfectly, so I would be fine with a one-off. Aesthetics are not important for this 'un.