leadscrew power calculation ( was Re: formula ?

Hi Guys,

Seems this is one of those standard mathamatical
problems that lends itself well to a spreadsheet.
and that spreadsheet would be GREAT to have in the
files section. (hint hint)

Obviously there are at least two different calc's

Direct is: rack style and leadscrew.
rack and gear is the other style.

Seems that a spreadsheet that also lets one
compare stepper/servo torgue from one system
to another is needed and wanted. I mean if
we use oz/in for nameplate and inch pounds for
calculations we need that.

I think most of have Lars Josefsson's program for
converting metric to SI to whatever.
http://www.steamesteem.com/index.html?units

but there is still that missing link.

Dave

--- In CAD_CAM_EDM_DRO@y..., batwings@i... wrote:
> I don't think this is correct.
>
> At 06:14 AM 4/15/02 +0000, you wrote:
> >docholliday01201 wrote:
> >
> >> once again, who knows the formula for converting rotational
torque at
> >> the motor-to linear force at the table ??
> >
> >Its really simple. Consider the leadscrew to be a drum pulling a
string,
> >where the circumference of the drum is equal to the lead of the
screw.
> >If you have a 5 TPI screw, that is the equivalent of a drum with
> circumference
> >of .200 in, or .0637" diameter or .0318" radius. If the motor
produces 10
> In-Lb,
> >that is the same as 10 Lbs pull at a radius of one inch. This
will translate
> >to 10 / .0318 = 314.16 Lbs linear force on the table! Pretty
amazing, these
> >ball screws!
> >
> >Jon
> >
> >
> >Addresses:
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