hi Brian, I had the same issue as well but it was only with one axis. It would spin beautifully in the one direction and when I jogged in the other direction, it would still move very slowly in the same direction as before, but very noisily (like a misfiring engine)
I isolated the problem by checking if it was the motors or the drivers or the board. It seemed to be coming from the board so I changed the (board outputs to drivers) numbers from 4 / 5  to 6 /7, and moved the axis outputs from 6/7 to 8/9. (essentially not using the number 4/5 outputs from the board). I also the changed the ports and pins output for the relevant axees in MAch 3 number ports and pins.

Not sure if it all makes sense to you but I will send pics, which will explain it no prob if you dont understand what I am saying.

regards
Thys

I see I'm going to try it, I think the problem may be that I am using too small gauge wiring, I'm going to change my wires to 18awg tonight and see if that helps. Right now my 5v signals are 24 awg and to my motors is two strands of 24awg which I think might be choking it. I read on a couple other forums that the sputtering is due to low voltage getting to the motors too so if the gauge switching doesn't help I'll try your method. Hopefully one or the other will work. Also you asked to see some projects, were you talking about in CAD form or actual finished projects?

hi brian, hope you come right tonight. Any projects, planned or completed.
regards
Thys

Motor tuning can be the culprit too. Too fast of an accel and or speed will cause stalling.

Update #3: ::sigh:: OK, so it was not the size wire though I feel more comfortable with the larger gauge wire. I switched ports that the signals are coming out of and that did fix some of the problem. So here's whats going on now. When jogging at 30% (which I'm not sure that means anything to anybody) all three motors jog wonderfully. However when I plug in a Gcode, the motors sound like a 30cal machine gun going off and is awfully loud. Now, the Gcode I'm running looks like a tomb stone and It starts on the round side of it so I don't know if it smooths out once I get to the flat edges however given how loud these are I'm not sure I want to.  So I'm googling like crazy to find a solution to this now... gotta love trouble shooting...

Ok Now here's my question, What is your dip switches on the motor controllers set at? I have 1-8 dip switches and all but 2 are up, so that should give me 3.0amp at 1 micro step. I'm thinking about changing it to 1/2 micro step but I wanted to hear what someone else had first

That is all for now

Thanks again for helping me get this far,
-Brian

ps  after reading over some earlier posts of mine I apologize for my awful proof reading (or lack there of )

hi Brian, i agree with fastest1 (quite appropriate name for this topic) your motors tuning could be too fast. i have run the motors too fast and that does cause a horribe noise. It would make sense that when jogging at 30% there is no issue but at full speed it is an issue.
to sort this out i need to know what lead screw pitch you are using (TPi) or (TPmm) and the what speed you have set your motors at in the Config - motor tuning page in mach 3 software. I think 1/4 microsteps are fine for what I am using but I am sure it differs from person to person and depends on the type of method you have used to move the move the axees. we are getting closer, so don't give up hope.
regards
Thys

Update 4: Ok, after following the advice of Fastest1 and a few others, I tuned my motors a bit and I was able to get my motors to perform a gcode with little to no grinding noises. I think after a little more tuning I'll be confident in installing the motors and building my machine WOOOO WHOOOO! So thanks guys for your help I really appreciate it!

PS I also had to move my y channels from 4 & 5 to 8 & 9 this solved the problem in which the motor would turn great in one direction but horrible in another. - Thanks for the tip Thys

Hi Brian, thanks for the update, I was wondering where you went!
great, I am pleased to hear it all worked out.
good luck with the next project

To all those reading this thread as reference purposes, please note that the sherline 1/2 pulse checked sorted out the problem. the motors are turning fine now. Tweaky was fantastic is assisting me patiently to isolate the problem.
May thanks to the adminstrators for setting up this forum. it was a life saver.
Heres to a long happy cnc journey!
Thys

What do you mean "please note that the sherline 1/2 pulse checked sorted out the problem. the motors are turning fine now." What is sherline 1/2 pulse? Thanks for any help. Tony
 

Sherline is an option you can choose, it makes the pulse 40uS wide so 25KHz kernel is the most you can use with it. Some drives require a wide pulse so it is needed for them.
Hood