is, if i threaded a rod with a 1-72 die, and i threaded a hole
with a 2-56 tap, will it make it much easier to screw in? or is that
the way it's supposed to go and i just didn't know that...
No, a 72 tpi. (threads-per-inch) rod will NOT fit in a 56 tpi. hole.
Often dies are made to be adjustable with a slot and set screw usually
arranged to push the opposing side apart slightly. If you have that
kind of die and the set screw is pressing the die halves apart it will
make a larger diameter screw. In that case, loosen the set screw to
allow the die to close more and make a smaller diameter screw.
If, on the other hand, your die is not adjustable and it’s cutting a
screw that’s too big, you can carefully MAKE it adjustable by grinding
a thin slot with a cutoff wheel (aim for the non-threaded place in the
center). Then squeeze the die with handle (limit the chance of
breaking it by using a shim in the slot) and it will cut a smaller