Quote Originally Posted by Duffman View Post
What ur sayin Jazz sounds about right for they sound as if they are struggling to move at times. I'm going to try and put a video up and let u see the way in which they are moving. Also can I add those lead shines to my nema23 motors which have four wired coming from them ??
Yep always going to struggle with direct drive and such large pinion.
Now other than Torque here's another reason why you want a ratio.? Looking at your Pics the pinion looks about 50mm dia which means your pitch will be around 157mm per rev which will give a ridiculous Rapid speed of 141,370mm/min or 141M/mtr Min and that's working on very conservative 900Rpm stepper speed.
This will mean at 100Rpm you'll still be traveling at 15,000mm/min which is still way faster than you'll cut at even with plasma. Now lets say you need to cut at 2000mm/min then your motor rpm will be around 13rpm and the action will be horrible.

So to give a sensible for plasma but still quite high rapid speed of 30,000mm/min you'll need 5:1 ratio using pinion of 50mm.
Problem with this size pinion is the size of the other pulley will need to be huge so using a smaller pinion is the answer. It will also lower the pitch and reduction needed which makes it easier to do.
But what should be clear is that you NEED a Reduction no matter what you use.!

Those motors will work with EM or AM drives but they will most likely be Series wound motors and high inductance which means they will lose torque fast when RPM rise. This means Voltage will be more important to get decent speed from them. But because your using reduction then you'll get away with it and can account for the lower RPm with it.