This is not exactly a model-engineering issue, but I know some of you
are involved with larger machines, so I'll ask anyway...
I have a threaded hole (in an old tractor, as it happens) which is 7/8"
in diameter and threaded 9 TPI. Looking at various tables leads me to
believe it's either Whitworth or UNC. A UNC tap will go in, but I don't
have a Whitworth tap to try. My questions are :-
1) Will a 7/8" UNC tap screw easily into a 7/8" Whitworth thread ?
2) If so, how else can I work-out which thread it is ?
16 years ago