[time-nuts] metric / English

Chuck Harris cfharris at erols.com
Sat Dec 17 07:48:53 EST 2011

Which works very well, but unlike all of the English
thread combinations, you must keep the lathe's half-nuts
engaged to the lead screw ALWAYS.  That means when you reach
the end of the thread, you must stop the lathe, and back
it up to the beginning of the thread to make the next cut.

With English threads the following rules exist for using
the thread dial indicator:

Even threads - engage half-nuts anytime
Odd threads  - engage half-nuts on any numbered line
1/2 threads  - engage half-nuts on any odd numbered line
1/4 threads  - engage half-nuts on the line you started with.

Metric threads are miserable to cut on English lathes...
and not much better on Metric lathes.  Metric thread dial
indicators are complicated and easy to get wrong devices.
With English threads, you would have to work to get it wrong.

-Chuck Harris

Don Couch wrote:
> Hi, Brooke,
> To cut metric threads on an inch machine, I mesh the 127 tooth gear with the 100
> tooth gear that came with my Sherline lathe threading attachment. Works great.
> Don Couch

More information about the time-nuts mailing list