Re: Force through ball screw based on stepper motor torque??

Hi Mike,

The force is being measured when jogging as slow as I can - I don't
recall the exact rate of feed, but probably less than 1" minute.

Chris




--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Mike Richards" <miker@...>
wrote:

>
> <Chris wrote: >
>
> > This problem (if it is) has been bugging me for some time now.

On

> > my CNC router, I can only get about 70-80 pounds of force on any

of

> > the 3 axes. <snip>
>
> Chris,
>
> When are you measuring the tourque? On my test bench, I only get
> HOLDING torque when the stepper is moving very slowly. Shortly

after

> stopping the stepper, the automatic current reduction feature on

the

> drive kicks in and reduces the holding torque substantially. On

the

> other hand, running the drives at speed usually puts the stepper in
> that part of its torque curve where torque is very limited. In

short,

> I would only expect to see full torque when the stepper is running

in

> its full torque range.
>
> - Mike
>