Re: Screwcutting Software

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Kim Lux <lux@d...> wrote:

> I don't know what would make you say TurboCNC is "hobby oriented". I've
> found it to have a nice set of features and we use it in a production
> workshop every day.
>
> Kim
>
>
>
> On Mon, 2003-12-08 at 09:01, glm59 wrote:
> > What software offers screwcutting as standard, i know about Ah Ah and
> > Turbo cnc, but are there any more out there mainly for the hobby
> > market.
> >
> > Gavin

I think he meant, are there more hobby-oriented programs than these?


But it seems that threadcutting would be a long Z-axis move with a
synchronized rotation of the spindle. Or in reverse, a multi rotation
spindle move, with a corresponding Z-axis move.

Although I have not done threadcutting on a lathe, I think TurboCNC
does it with one rotation sensor, and no mid rotation correction.

On the surface, it sounds as though it can be a very elaborate routine
with multi rotation sensors, and a fast algorithm to adjust the Z feed
rate, but on the other hand, if nothing moves, (part slips, tool slips
etc:) then a single point threading can be open loop in a more simple
way.

It seems that if one is controlling the spindle as a linear axis (servo
with feedback?) and can lock the spindle to the Z axis for synchronized
movement, it could be as simple as one revolution being equal to the
thread pitch, then synchronizing the Z to move at the same rate.

After all, if one were to unwind a thread into a 2 dimensional chart,
the line would be perfectly straight and on a known angle.




Dave