RE: rolled ball screw - STANDARD SCREW INSTEAD?

Here is my understanding of the different types of threads:

ACME thread (rectangular) is used in machinery, because the sides of the
wall are used to transfer power, and not grip.
_|~|_|~|_|~|_|~|_

Triangular threads are meant to grip and bite, and not used to transfer
rotary motion into linear motion.
_/\_/\_/\_/\_/\_/\_


Buttress threads are meant to have staying power, so it won't budge and
hopefully won't vibrate out.
_/|_/|_/|_/|_/|_/|_


Hope that helps. (if my ASCII drawings don't come out, oh well)

Cheers

-----Original Message-----
From: Miroslav Pejic [mailto:peja@...]
Sent: January 27, 2003 11:26
To: 'CAD_CAM_EDM_DRO@yahoogroups.com'
Subject: RE: rolled ball screw - STANDARD SCREW INSTEAD?


Hi,
I need your opinions about using standard (but polished) screw with
triangular thread,
for example: 20 mm diameter and 2,5 mm pitch.
What about linearity?
Peja