Mini Mill to cnc Project log

[moto21]

Hello all. I decided to start a project log for my new mill conversion. I started out building the controller before I knew what I was putting it on, yes I do that a lot. I’m using a 24VDC, 6.5A power supply that powers 3 gecko G201 drivers and cooling with a 4" ac fan. As for motors I’m using automation directs 434oz-in Nema 34 steppers. .I am using mach 3 for control through a winford dbl25 breakout board. I’m getting excellent torque out of this setup with good motor speed. As for my mill I bought a Cummins mini mill. I just received the mill Monday and I’m finished to clean it up. My plans are for now to use the current lead screws until I build up some funds again for ballscrews plus that will give me the setup I need for the ballscrews. I also plan on installing a two speed belt drive and add a spindle lock in the near future. Any suggestions, questions, or complaints are welcome. Any thing you want to see more detailed just ask. I’m more that happy to help.
~Brad

[JFettig]

looks like a good project, but you may want to consider automation directs smaller steppers, if you take a look at the torque/rpm curve, the 272oz-in motors pass up the larger ones quickly.
although if you go with the stock leadscrews it is likely it wont be that big of a difference, but youre likely to get higher speeds with the 272s on ballscrews.

Jon

[moto21]

To late. I already have the 434's but Im happy with them. I have already got the main plates done for the x/y axis. Its coming alone nice.

[JFettig]

How do you plan on doing the z-axis?

You might find that you will need ball bearings in the y-axis. with the 272s on the the recent mill I converted, I couldnt get more than 12ipm out of the y-axis with regular mount, but with ball bearings I was pushing 40+IPM

Jon

[moto21]

For right now I plan on using the rack and pinion gear on the Z. Just to play with for now because I to wait and do the z axis When I have the ball screws. When I do get the ballscrews I plan on running the z axis alone side the dovetails or maybe down the center. I'm planning on doing ball bearings on all the axis but not right away. I want to get the main setup done and then make improvements from there. Thanks for your input Jon, I look at your mill alot to get ideas.

Brad

[moto21]

Little update. I worked some extra hours this weekend and got some money around so the mills on hold until wensday when my ballscrews and nuts come. I also have ball bearings for the ends of the leadscrews coming. Its fun being broke.

[jjwl89]

Your conversion looks good so far. Where are you geting your screws from? Will you be machineing the ends yourself?

[moto21]

I got them from mcmaster-car. Im doing the maching myself. I have a fair size manual lathe and mill. I should be able to start maching them tomorrow as long as they show up. I also have the z axis almost done excluding ballscrews and mounting. I'll have some new photos soon.

[moto21]

Well I just got done Grinding the ballscrews on my lathe. They came out Very nice. I still have to make the ball nut mounts before I mount them. Well I'm off to the hardware store.

[moto21]

Got the x and Y axis mounted to day with the motors and running smooth. Im still working some bugs out of the z axis but thats also almost done. Im also currently cleaning up my wiring in my controller box because the wiring for testing was a bite messy. Im aslo adding some little things like a e stop, indicator light, and heat sink. well back to work. So much to do so little time.

[acondit]

Moto21,

Where did you get your Lovejoy connectors? What did they cost?

Alan

[moto21]

I got them from ENCO. Heres the link. Remeber you need 2 hubs and 1 spider two make 1 coupling when you order.