Re: [CAD_CAM_EDM_DRO] How does a polygon turnign lathe work?

it looks like a single point cutter that's moved in and out depending
on the angle of rotation of the cutting head.

The cutting head spin is synced to the lathe rotation by the shaft in
the back, so the two are moving in lock step. I'm guessing it's not a
1:1 gear ratio, otherwise the cutter would hit the same spot every
time.

On Fri, Oct 7, 2011 at 12:23 PM, Douglas Vogt <dbvogt@...> wrote:
> The flats may be concave after all but not noticeable at this diameter. Look at the second video from citizen showing slow motion. The cutter makes a much larger diameter pass on a relatively small diameter piece. The larger the diameter cutter and smaller diameter work piece, the less concave will be the flats of the hex. What is surprising is that the cutter diameter is under CNC control as well as in the video you cite - the cutter makes a second larger hex closer to the chuck without missing a beat. It seems the number of "axes" in a machine can be extended well beyond what we're used to. All possible due to CNC.
>
> Stop the video several times and you'll likely see a perfectly consistent reflection on the flats as if they were truly flat. Stop it at 1.02 and you see the top and bottom parts of the flat shiny but the middle of the flat is darker suggesting concavity.
>
> Of course, this completely a guess :-)
>
>
>
> From: danmauch <dmauch@...>
> To: CAD_CAM_EDM_DRO@yahoogroups.com
> Sent: Friday, October 7, 2011 11:44 AM
> Subject: [CAD_CAM_EDM_DRO] How does a polygon turnign lathe work?
>
>
>
> I saw thisamzing video http://www.youtube.com/watch?v=KMdBIBzGtKI and can't quite figure out how the machine is cutting the hex so perfectly. I do see that the cutter is just a staight bit and see that the millhead is syncronized via drive shaft to the spindle. But with the cutter on the perimeter of the milling head I would think the hex flats would be concaved. So how does the machine actually work?
> Dan
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> 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
>
>
>
>