Drill size for 6-32 tap?

[MRogersII]

Should a #35 or #36 drill be used for a 6-32 tap in mild steel? I've seen references for both.
Thank you

 

[WSnyder]

I’d lean toward the #36. You could use the #35 for about 70% and it’d probably be fine.


A #37 would be 84% thread engagement.

 

[GenePoole]

I would use a #37 (0.1040 in) . The minor for a #6-32 is 0.1042.

 

[MRogersII]

View attachment 1509240

Thank you, Sir. I had seen references for both so I did a test in a piece of scrap al with the #35 and the tapped hole seemed pretty sloppy with a 6-32 screw. As it happens, I have about 10 #35's and 0 #36 bits.
Thank you again
Michael