Hole size for self tapping M4 x .7 screw?
- 1 decade agoFavorite Answer
2.5 mm drilled hole.
- Thomas SLv 61 decade ago
3/16 approx. The 4 is hardness, 8 being very hard. With a four you should be able to self-tap through 1/8" mild iron. With an 8 up to half inch of iron.
- 1 decade ago
no sure off hand but for future use if U have a drill hold, one or the one that has holes cut in it for each specific drill bit, or a drill bit guide.
Use that to put the screw into, if with wriggling the screw around, not turning it, U can push the screw into the hole, then go for the next one down, if it even jumps one turn use the smaller one, that's what i do.
i hope this helps for the future