Re: Formula? for determing torque of motors and leadscrews.

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Damon" <damonfg@y...> wrote:

>
> I found the formula but it looks wrong. Using it with all others
> equal, ballscrews required much more torque than acme screws.
>
> Just subscribed today, and would love to know the secret
> formula to stepper-driven happiness !
>
> I'm starting with a large mill/drill (8"x24") and acme screws.
> Hoping to upgrade to ballscrews and a fullsize b'port or the like.
> But really only want to buy one set of motors. 740oi? 1070oi?
>
> -d

doing the math, it seems that a 740 into a 10TIP leadscrew would
deliver a theoretical 2,905 lbs.

(2 * PI * 10 * 740 ) / 16 = 2,905
10 is tpi
740 is oz-in of motor


2905 * 90% = 2,615 delivered pounds for ball screws
2905 * 60% = 1,743 delivered pounds for ACME high eff
2905 * 30% = 871 delivered pounds for ACME low eff


as a side note here, when talking about using all-thread or ACME or
ball, considder that you would need a motor and driver almost 4 times
as large to move the same load as a ball screw. talk about the best
place to put your money !

>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "turbulatordude"
> <davemucha@j...> wrote:
> > This is a good reference.
> >
> > Thanks Jon and Mariss
> >
> >
> >
> > --- In CAD_CAM_EDM_DRO@yahoogroups.com, "hllrsr_uk" <hllrsr@c...>
> > wrote:
> > > Guys,
> > > After spending a couple hours searching the archives I'm in

need

> of
> > a
> > > lead.
> > > I can remember someone (Mariss? Jon?) posting a formula for
> applied
> > > force that used motor torque, gearing, and screw pitch.
> > >
> > > If anybody knows the formula, or knows a better way of

searching

> > the
> > > archives, PLEASE pass it on.
> > >
> > > TIA
> > > Iain