Re: Feedback on Free stepper calculator

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Don <donkiwi@y...>"
<donkiwi@y...> wrote:

> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "Fred Smith <imserv@v...>"
> <imserv@v...> wrote:
> > Did anybody get a chance to check the calculations on the rack

and

> > pinion and pulley ratio calculations on the free stepper motor
> > calculator?
> I did a quick check of the Screw calculations using my program in

the

> Group Files area, ~ Or was I checking mine against yours? :)~, and

it

> all seems kosher.

Thanks for checking Don.

> The Rack and Pinion figures I found confusing, however.
>
> I assumed that the units are: Pinion: [Teeth]; Rack: [T.P.I.] (and
> not "pitch", as labelled, although it seems that "(1/T.P.I.)=pitch
> [ins]" has been applied).
>

Rack are sold by diametral pitch (DP) which is different from screw
pitch. A 12 DP pinion with 12 teeth will have a 1 inch pitch
diameter. This yields a distance traveled of pi per revolution on a
12 DP rack.

> A quick test:
> I set the stepper motor to 200 [steps/rev],
> Stepper to 3.33333~ [steps/sec] ( =200 steps/min = 1 r.p.m.),
> and the Rack & Pinion values both to "any-same-figure": "N".
> The resulting speed seems to be suspiciously involved with "PI",
> whereas it should produce a linear speed of 1 inch per minute,

based

> on my assumption.
> Has someone "pied" your calculations when your guard was down

Yes they did and it is correct that way.

The units required or effects of each fill in blank are indicated in
the bottom left of the screen when you mouse over the fields.

As far as the plain jane layout style, beggers can't be choosers. ;-)

It's a gift after all.

Best regards, Fred Smith - IMService