Re: Making Stepper Pullys

Hi John,

I've examined the "TimingBeltpulleys.xls" file, what I saw was a table
of "MP, XL, H and L" series pulleys, with pitch, depth of cutter and tip
width for each. Does the spread sheet do more? (I've sent Bill a PDF
made from the XLS file). I have, in the past, ran a "export macro" (I
didn't write it), and exported comma delimited data. That data I was
able to incorporate into a specialized program, much like we'd like to
do here.

COGPULY.C by Marvin. W. Klotz is a step in the direction Bill would like
to go. It is based on calculations in an article by John Cooper, who as
Marvin puts it: "wrote one of the best articles on homeshop gear making
I've seen". For those of you who haven't seen it yet, the reference is:

"Spur Gears and Pinions" by John A. Cooper
"Machinist's Workshop", 4/99, Volume 12, Number 2, pg.8

The program is functional, but as Marvin comments, that " but we were
never able to get agreement with the results in the original article - I
suspect a mislabeling in the article."

If we could resolve the discrepancy between the article and the program
output, we'd have a base for generating Gcode to cut timing belt pulleys
to spec!

I think Bill wants to make multiple passes on the tooth profile,
starting before, on, and after centerline. I'll let Bill quote it from
the article. This, I'm told allows cutting the tooth profile with a
simpler cutter (I think).

Ideally, a program could generate these multiple passes, depths, and
indexing for various tooth pulley dia's (tooth counts).

"timingbelts.pdf" had a limited amount of tooth profile information, I
don't know that a cutter profile could be created from it (from my
limited "tooth" experience), or if we can use the information to resolve
the discrepancy.

Apologies to anyone that I misquoted or misunderstood, and for jumping
in the middle of this "project". Corrections requested!

HTH

Alan KM6VV


machines@... wrote:

>
> >--- In CAD_CAM_EDM_DRO@y..., wanliker@a... wrote:
> >
> > You are of course right, but I could never get anything out of it,
> >as I did
> > not have EXCELL, but one other member tried it, and also could not
> >get
> > results, so it passed out of my memory banks. Thanks for the
> >reminder, I
> > hang my head.
> > bill
> >
> >
> OK Bill,
> That's got that sorted. What software do you have that can read a
> spreadsheet?
> I can rework the program to get it to do this and repost the file.
>
> John S.