Re: Step resolution question, dividing head

Jon,

My first thought was the same as Peter. You sure it's only 4:1?
Since you describe 1 turn for 90 degrees, it prob'ly is...

Math seems ok, but I'd question the reliability of such fine
microsteps in this type of application. I'd look for a stepper with 1
degree steps, and use a divide by ten microstep driver. This gives me
3600 steps per rev (90 degrees), so 40 steps per degree (.025 degree
resolution). 1:1 drive.

If you can live with this resolution I think you will have a much
more reliable setup. Should cost less too!
Hope this helps.

Ballendo

P.S. If you need the increased resolution, I'd build it into the
drive ratio, NOT the microsteps!

--- In CAD_CAM_EDM_DRO@y..., Jon Anderson <janders@n...> wrote:
>I'm working on setting up my Hardinge dividing head for a 4th axis.
>I think I've figured out a ratio that gives me even steps, at least
>for full degree moves, and wanted a double check that I did this
>right.
>Dividing head has 4:1 ratio, so 90 degrees per full turn of the
>handle. With 18,000 microstep resolution I get 200 steps/degree and
with a 2:1 reduction between motor and dividing head, 400 total
microsteps/degree, or .0025 deg/microstep.
> Does this look OK? I need to get the ratio settled so I can pick
exact
> timing belt pulleys, and finish designing the mounting plate.
> Thanks,Jon