"Duane Bozarth" wrote in message
...



No, it's simply a choice of the vendor...many carriage bolts aren't
fully threaded...

Ok

And a machine (hex) bolt is often used to tie two pieces together so a
nut is used just as w/ a carriage bolt. All depends on the application.

My reference was such as a machine bolt used for head bolts on an engine.
No need to thread the whole bolt when the end is all that will engage the
block. But like you said it all depends on the application