Re: My dream! - Torque

Gerry, Jan

Thanks - is there some kind of formula that links torque and X-Y
size? Or is the weight (inertia) of the moving carriage the issue?

Using force = mass x accelaration My conclusion is the heaviest
object must have enough accelaration from rest to move the step
distance before the next pulse. The solution then is light carriage
or big motor or slow pulses when ramping up to full speed. Am I
right?

After measuring my shed an XY size of 2ft x 3ft (or maybe 2ft x 2ft)
is more realistic than 1m x 1m. Would 110 oz motors then be
sensible - if not what is the max size/weight for 110oz motors?

And if later I added encoders and a PIC, surely smaller steppers
would be ok because the PIC would adjust for lost steps?

Many thanks for answering these beginner questions!

-Paul

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "notoneleft" <ger21@c...>
wrote:

> Yeah, like Jan says, I'd go for ACME or metric trapezoidal, and at
> least 250 oz-in motors, 400 if you want to go fast. But fast costs

$$$

>
> Gerry
>
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, JanRwl@A... wrote:
> > In a message dated 6/26/2004 11:06:03 AM Central Standard Time,
> > paul3507@b... writes:
> > What have I missed apart from a few weekends of work?
> > Paul:
> >
> > The size of X-Y you ponder, with "V-thread" lead-screws, even IF
> stainless,
> > will require MUCH more stepper-motor than 110 oz-in! Even if

you

> were
> > pondering preloaded ball-screws, I'd go for more like 400 oz.in.
> per axis!
> >
> > Further, your best bet is "bipolar chopper".
> >
> > Which is less expensive, GOOD stuff that WORKS, or "surplus
> leftovers" that
> > won't function in the intended purpose?
> >
> > Lotsa luck! Jan Rowland
> >
> >
> > [Non-text portions of this message have been removed]