Spanner nut set screws replaced

[Logan Novice]

Spanner nuts on my PM1127 rely on a slotted set screw that is a PITA to tighten. l Found a M4x.70 cap screw through ACE Hardware at .65 cents each. Much better. And with a tiny bit of leather in the bottom of the hole it doesn't damage the threads on the gear axle. I chose the leather because it protects the threads and stays in the threaded hole when removing the part - a brass insert just drops out when the part is removed.
Adjusted the fit:
I did find that the head on the cap screw was a tiny bit wider than the spanner nut so I turned if down a couple of thou. so it doesn't contact the face of the adjacent gear. I just bored a scrap and threaded it for M4x.70 and used that as a base for holding the cap screw while I turned down the head.

 

[benmychree]

A little hunk of brass might have been a better choice than leather.

 

[7milesup]

If you could go up one size and change to SAE threads you could use a brass tipped SHCS's. One size up looks like a #8 SAE, but you may have to use a #10 to get the threads cut properly.

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[markba633csi]

An 8-36 screw is nearly identical to an M4 screw, FYI
-M

 

[Batmanacw]

I changed mine to set screws today because of this post. I don't need to snug mine that tight so I didn't use brass. They work much easier now for sure.