Re: [CAD_CAM_EDM_DRO] cnc lathe - threading - alternitive method? (more-info, please read)

That is a very good point you made.... so, lets say one wants to turn a spiral (wood) using a thread theory in that the spindle speed needs to be coodinated with the z feedrate.... you would think there would be some sort of equation for spindle rpm, number of spirals per inch, and z feed rate and the x depth.....

Just a thought,
Russ

ps To all of those people who answered with a feedback type of control, this is what I am trying to work AROUND,,,,,not with.

Jon Elson <elson@...> wrote:

Russ Waters wrote:

>Hi to the group..... I need to pick your brain on this one!
>
>I would like to come up with a alternitive method of threading with a cnc lathe,,,,, not using a feedback system with conjuntion of the G33 code, but would it be possible to cordinate the spindle speed with the feedrate of the z axis to do threading? I think it could be done, has anyone tried this, or have a theory on how it could be done????
>
>

Yes, but....

The problem is that there will be no precise relation between the
spindle and
the Z axis feed, so the thread will be an APPROXIMATION of the desired
thread
pitch! If your spindle speed were held within 10%, then you'd get a
thread pitch
that was somewhere within 10%. So, for a 32 TPI pitch, you'd get
something within
29 and 35 TPI. IS that good enough? I suspect not, for most purposes.

Secondly, you would have no way to make multi-pass threads. Every
thread would
have to be cut in a single pass. Think you can cut an 8-TPI thread in
one pass?
Hmmm, I'd like to see your lathe!

So, these are the reasons why feedback is used.

Jon



Addresses:
FAQ: http://www.ktmarketing.com/faq.html
FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/
Post Messages: CAD_CAM_EDM_DRO@yahoogroups.com

Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com, wanliker@..., timg@...
Moderator: pentam@... indigo_red@... davemucha@... [Moderators]
URL to this group: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO

OFF Topic POSTS: General Machining
If you wish to post on unlimited OT subjects goto: aol://5863:126/rec.crafts.metalworking or go thru Google.com to reach it if you have trouble.
http://www.metalworking.com/news_servers.html

http://groups.yahoo.com/group/jobshophomeshop I consider this to be a sister site to the CCED group, as many of the same members are there, for OT subjects, that are not allowed on the CCED list.

NOTICE: ALL POSTINGS TO THIS GROUP BECOME PUBLIC DOMAIN BY POSTING THEM. DON'T POST IF YOU CAN NOT ACCEPT THIS.....NO EXCEPTIONS........
bill
List Mom
List Owner


Yahoo! Groups Links









---------------------------------
Do you Yahoo!?
Yahoo! Search presents - Jib Jab's 'Second Term'

[Non-text portions of this message have been removed]