"Eisboch" wrote in message ...
This is such an easy answer, I can't believe nobody has answered correctly.


You use a coarse thread bolt when the only nuts you have that match are
coarse thread.
You use fine thread bolts when the only nuts you have are fine thread.

You give up and head for the hardware store when one is metric and one is
standard and they are the only ones that will work for your project.


Eisboch (yeesh.... why is this so difficult?)

Pretty much correct, except, even with a quite large bolt and nut bin,
I usually get tired of hunting after a few seconds, and head for the
hardware store anyway! One day, I hope to need a bolt, and actually
find the right one in my bucket!