Hi all.

I have been lurking around for the past two or so years gathering info for my own cnc lathe build. I have been putting some more time into lately and looking forward to the final stint. Some pics....









Lots of neatening up to do and work on the cabinet.

Now for some questions.

The Z axis is direct drive. I have the driver set at 2000 steps and the Mach3 steps per rev at 400 (2000 divided by 5mm pitch ball screw). Is this correct as this is giving me accurate readings.

Secondly what do I set the Mach3 step pulse and dir pulse at?

I have tried to setup the MPG but when I use it the saddle goes bananas.......jerking forwards and backwards.

Anyone know a good retailer of timing belts?

I'm sure I'll have more questions when I set up the spindle timing and VFD.

Thank you.

Joe.

Hello Joe, Welcome to the forum!

Your steps per sounds right to me when I do the math if your native units are set to MM.

Set the step and direction pulse width to 15.  You may also want to try to enable Sherline 1/2 step mode in config., ports and pins, port set up page.

Get all other motion nailed down first.  Make sure you are moveing the right distances and not skiping of looseing steps and then we will look at the MPG.

http://www.sdp-si.com/  Timing belts

Brett

Nice lathe Joe!  You're gonna love it when you get all the bugs worked out.  Hopefully you'll have better luck than me.  Seems like the list of things to do on mine gets longer instead of shorter.  The more things I learn and get working, the more I need to do!

You probably already know this but it'll be a lot more rigid with that compound removed.  Just make a solid steel block of the proper height to mount a QCTP directly onto the carriage.  We don't need no compounds anymore.

Thank you for the comments guys.

So far a G code of Z50 is giving me 50mm in the Z. A code of X12.5 is giving me 12.49 in the X. I'm stoked so far.

The compound will be removed eventually. You will notice a third stepper driver in the cabinet.......future tool changer.

Just waiting on some timing belt gear for the spindle then I'll get stuck into getting the chuck turning.

Once I get this running well it will be time for the next project......