On Fri, 6 Jun 2008 19:02:24 -0700, "Michael Koblic"
wrote:

I have spent a very long and unproductive day trying to cut a 5/16-24 thread
on a cut-off piece of 5/16 bolt.
I knew things were not going to go well when I could not get the
*never-previously-used* die to even bite. I chamfered, then chamfered again,
nothing. eventually I made the tip almost conical. I got some purchase but
a) the effort to cut was disproportionate and b) the end result was a thread
which was skewed - and not subtly!
I tried again with another piece of 5/16 rod - same result.

I hit the books to see if I omitted something glaring. Most of the texts I
have are big on starting *taps* straight but they did not stress the dies so
much.


I had the identical problem with a new chinese die. 1/2 inch national
coarse thread.

I persisted until I got the rod threaded. beautiful thread in the end.
.....but 1.2mm under spec diameter! no wonder it wouldnt engage on the
rod.

I went out and bought an australian made die and had not a problem
threading the rod. and it was bang on spec diameter.

throw your die at the neighbours cats and get one made by a quality
manufacturer. your die is more than likely a piece of garbage.
Stealth Pilot