The short answer:

For a smaller wood and plastic cutting machine (and maybe – maybe! – some light aluminum), several people on CNCzone seems to have had success with 100-200 oz-in (0.7-1.4 Nm) stepper motors direct driving a 5 turns/inch (5 mm lead) ACME (trapezoidal) screw.


The long answer:

... hopefully you can find in the attached file. Please, if you spot any errors or have trouble viewing the file (like missing characters or fonts), write a comment in this thread: http://cnczone.com/forums/showthread.php?t=5639, or use the email address in the file to notify me. Other comments are also welcome to my email address.

Arvid

Very good reading material Arvid,

I'm going to have to look up the data sheet information for my steppers now.

Maybe one of you have already done so and could post the specs. The steppers are from a few old HP Laserjet III's

LABELED: Astrosyn
TYPE: 23LM-C701-01
P/N: RH7-1048 04
5.2 V/Phase
1.4 A/Phase
1.8 Degree/Step

First, thank you for this document. Second, this may be a newbie thing to do, but there may be a typo in your PDF.

For the power equation you specify that it's force times speed (or velocity) but you write it at Force times distance F * s instead of F * v

Third, I am creating a spreadsheet of the equations as a tool, and ifthere is any interest I can make a web form. We'll see.

Jay

Jay,
It would be great to have that kind of information available if it's not already on this site.

I'm going to have to look up the data sheet information for my steppers now.

Maybe one of you have already done so and could post the specs. The steppers are from a few old HP Laserjet III's

LABELED: Astrosyn
TYPE: 23LM-C701-01
P/N: RH7-1048 04
5.2 V/Phase
1.4 A/Phase
1.8 Degree/Step

Check out the attached PDF for specs, pictures, internal wiring, etc. I hope this helps...

I have this Stepper motor and have tryed it using my Sherline mini Mill.
The following plastics were tryed:
Delrin Great at slow feed rate
Acrylic nice finish but needs lubrification(I use 10W30 motor oil)
Lexan Great at slow feed rate might be ok to mill at higher feeds if lubricant is used.

This motor does not have the force to feed a larger end mill(Grizzly 1005).

I have retrofit over 300 milling machines, and the only thing i can say to you is, there is not that much cost differance between a 200 oz in stepper and larger ones. Go with as large of one as fits your machine and budject. dont risk going to small.