Re: Std vs. stub acme threads

Bill,

From: http://www.normas.com/ASME/pages/B1.8.html

General and historical when formulated prior to 1895, regular acme
screw threads were intended to replace square threads and a variety
of threads of other forms used chiefly for the purpose of producing
traversing motions on machines, tools, etc. for current information
on acme threads, see the latest edition of ASME/ANSI B1.5. The stub
acme thread came into being early in the 1900'S. Its use has been
generally confined to those unusual applications where a coarse-pitch
thread of shallow depth is required due to mechanical or
metallurgical considerations.

Acme vs. Ball for z axis weight? Acme typically will not back-drive
due to gravity, whilst ballscrews/nuts generally will. All other
considerations favor the ballscrews ,IMO.


Hope this helps.

Ballendo

P.S. FYI, Your 12 line sig often does not display correctly.

--- In CAD_CAM_EDM_DRO@y..., Bill Vance <ccq@x> wrote:
> Can anyone tell me about the differences/features of std vs. stub
acme threads?
> Would acme be better than ball screws for moving a lot of z axis
weight?
>
> Thanks.
>
> Bill