Identifying hardware???

[Josephryanevans]

Hey folks,
So I’m missing a bolt from the tuning hardware on my mandolin. I’ve taken out an adjacent bolt to identify what I need for a replacement. But I’m stumped. It’s too small for my local hardware stores to ID with there measuring equipment and it is certainly too small to fit any of their nuts. I don’t even know if it’s metric or standard. I measure the diameter at 0.1 inch. That makes me think it’s either a #3 standard because that measurement doesn’t seem to fit any metric measurements. But a #3 doesn’t even seem to exist.

Any ideas?
Thanks,
Joe

 

[38 Dodge Coupe]

I just rebuilt a banjo uke that was a family piece. I got all of the parts, tuners, strings, saddle etc on line. Not sure what part you need but I had many vendors to choose from at very reasonable prices


Sent from my iPad using Garage Journal

 

[Mr_fixit]

Got a music shop nearby? They fix instruments. That means they have or can get parts.

 

[californiaHank]

If it's an American made instrument, it's unlikely to use metric hardware.
I don't understand your comment about "#3 doesn't seem to exist".

3-48 UNC machine screws are pretty common.
3-56 UNF machine screws are also available, but somewhat less common.
Both of those have a nominal diameter of 0.099".
3-48 UNC is coarse thread - 48 threads per inch.
3-56 UNF is fine thread - 56 threads per inch.

You should be able to check the thread pitch with a ruler and a magnifying glass.

You didn't say what kind of head they had, but if you're ordering from someone on-line, you measure the length differently depending on the screw head type: For round head screws, you measure the length of the threaded part only, not including the head. For flat head screws, you measure the length of the whole screw, including the head. (Google 'machine screw head types' for pictures if you're not sure of the difference.)