Screw threads

[MooseFET]

One can have as fine a thread as one wishes (say 80TPI max); the
alloy makes no difference.

I guess I should have qualified that with "for the given bolt size"
and it wouldn't have been misunderstood. Still into a casting a
smaller bolt is not as reliable.

 

[Don Bowey]

(snip)

I've often said "screw threads" as I brought out the riveting tool.

 

[Robert Baer]

I guess I should have qualified that with "for the given bolt size"
and it wouldn't have been misunderstood. Still into a casting a
smaller bolt is not as reliable.

I would hazard a guess that the finest (erliable) screw thread one
should do is 40TPI in casting.

 

[MooseFET]

I would hazard a guess that the finest (erliable) screw thread one
should do is 40TPI in casting.

I'm sure it depends on the casting but I've had #4-40 screws fail in a
casting. We switched to a machined part.