Hammer Screw Thread

[Bruce Day]

What is the proper thread designation for an external hammer screw? The screw that holds the hammer to the square post.

[Brian Dudley]

XXX

[Tom Carter]

Hammer screw threads are 4-42 for external hammers..

[Brian Dudley]

I stand corrected. I was going off the top of my head. I trust Tom, he makes them Often.