I've never dealt with stepper motors before, but have done a far amount of research on them. I'm trying for my first DIY CNC, so it's going to be trial and error for me. So I bought some small steppers from ebay, not sure how strong they are but hey they were $15+shipping for 5, however I'm trying for a small 12" x 12" CNC mostly for engraving and small parts. I was wondering what strength motors are people using for anything from a small CNC to a full blow big one.

There are way to many variables to say, a small 12"x12" i would go no lower than 100ozin, on my 4x4 i use 425ozin motors, 2 on X-Axis and one for others.

Do you have pictures and specs of what you bought how many wires etc.

Joe

I dont have spec, but they are tiny. There are about 1.75" square, 4 wire, bi-polar.
Heres the link (if it works) http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...N:IT&ih=017
The have a gear pressed onto the shaft, so if torque is an issue, i can always use another gear on the acme shaft and use it as a reduction gear. Better accuracy, higher torque, but slower speed. I have 5 total, so if i need (or can) double up on motors i could.

Well as far as i can see, i think they are around 100-160 oz-in holding force. I could only find a 24v model, where mine is a 12v. They are the same size, and manufacturer, however the ones i have are custom for some other machine manufacturer. I'm not sure about these specs tho. I guess i could hook up 12v to one pole and test the holding strength. That would work without the use of a controller right? I'm not trying to see moving force, just holding for now. I guess a good holding equals a good moving force. Someone able to shine some light on this?

Well i tested the motors I have. I put 12V DC on one set of coils. And it did what i thought it would, just lock into a hold position. Well I could break the hold. however not very easily (there gear digs into my fingers pretty good trying to get a good grip) So I see if i were to do a 3 to 1 reduction (if i even need it at all), I think i should have PLENTY of power to do a small CNC etcher. I'll post pics when I get something working.