CAD CAM EDM DRO - Yahoo Group Archive

Subject: Re: AMAZING STUFF!

on 2000-03-12 11:53:46 UTC
I try to read the messages pretty regularly but don't contribute a lot since
there always seems to be someone out there who has the answers to questions
that arise and so my own comments are usually superfluous -

However the point about a system of using a DRO of some kind to "close the
loop" on a stepper motor is something that to my knowledge has been around
for at least 25 years - I've been using and working with NC and CNC for
nearly 35 years and this concept has been used several times with various
levels of success -

The implementation of the electronics is pretty straightforward with the
software being more complicated and overcoming the realities of the physics
of machining with "backlash", "hysterisis", or "wind" in the system being
the most difficult problem of all - It has been said, after all, that you
"can't fool mother nature" -

Electronics and computer software can be pretty wonderful stuff but
machining using CNC with backlash can be a really frightening experience for
those who are unaware of the amount of kinetic energy that can be stored in
the resulting flying parts caused by mixing backlash and CNC - As someone
who has had the misfortune to be in the way of such flying pieces and had to
endure the resulting personal damage I would hate to see someone else have
the same problem because I didn't speak up -

On another topic - I'll issue another invitation to display or participate
in the CNC seminar to be held in Wyandotte Michigan at the annual NAMES show
- End of April - Contact me for more details off list if you are interested
- Several folks have already signed on and it is always a pleasure to meet
and greet people with common interests -

Roland Friestad
cardinal.eng@...

Copy of message follows
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Message: 10 - Digest #399
Date: Sat, 11 Mar 2000 18:17:27 -0000
From: "james owens" <wotisname@...>
Subject: Re: AMAZING STUFF!

Some time ago I proposed a system using DRO input to a CNC program for
stepper motor control of workshop machinery. The idea was considered to have
"No Merit" and not of commercial value. I proposed it as a means of using
lead-screws that have some wear and still achieving an accurate CNC
machining centre. I have continued to develop my thoughts and am close to
achieving the required results. It has taken so long because it was
necessary for me to start from scratch without the benefit of readily
available components.

Is this a case of parallel development or piracy. Don't get me wrong if this
is piracy Dan has every right to produce this application but it would be
nice to have been given a little recognition.
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Discussion Thread

Roland Friestad 2000-03-12 11:53:46 UTC Subject: Re: AMAZING STUFF!