Re: [CAD_CAM_EDM_DRO] Z axis servo reduction gear

Actually that is the same equation. I split the efficiency out for later
so your equation becomes:
Force= [Torque x 2 x Pi]/ Screw lead
screw lead is 1/TPI so the equation becomes:
Force= [Torque x 2 x Pi]/[1/ TPI]
Tidy up the divides:
Force= Torque x 2 x Pi * TPI

I always go for very pessimistic efficiency numbers to allow for dirt in
the nut, wear and extra friction from bearings, slide ways etc. I also
rounded the numbers down for the same reason.

Les

H & J Johnson wrote:

> Les, just for the record I've been given a totally different equation
> to calculate force from a screw.
> Force= [Torque x 2 x Pi x Eff]/ Srew lead
> F=lbs
> T= in/lbs
> Eff =x/100 or [0.xx]
> Lead=inches
>
> In that instance w/ a delrin nut I'd think it would be at lease 30% efficent
> 50oz-in = 3.13 lb-in
>
> f=[3.13 x 2 x pi x 0.3] / 0.10
> f=60lbs
>
> Sorry to cloud the numbers
>
> Just thought I'd throw that out there anyway.
>
> Jarrett J
>