Lathe Conversion, PM1228 to CNC

[AlanB243]

Very nice CNC conversion.

On the BLDC motor, I suspect the controller is the main problem. Before changing the motor it might make sense to try a quality BLDC controller. I suspect the motor is capable but the electronics aren't doing a great job with it.

[maxspongebob]

Very nice CNC conversion.

On the BLDC motor, I suspect the controller is the main problem. Before changing the motor it might make sense to try a quality BLDC controller. I suspect the motor is capable but the electronics aren't doing a great job with it.

I have looked high and low for a BLDC controller that will work better. I had a thread on it here. https://www.cnczone.com/forums/spind...78956-cnc.html I actually bought a controller from Anaheim Automation (very nice). The only problem was that I lost some RPM because the controller output 170VDC and the motor wanted 230VDC.

After giving up on that combination, I went back to the Chinesium controller that came with the lathe and got it to work with an interface card. See this thread. https://www.cnczone.com/forums/bench...-sx4-bldc.html This gave me the voltage I needed but the rpm and stability is just not there.

Any help or suggestions you can provide would be appreciated. Thanks.

[AlanB243]

Sorry I don't have any specific recommendations, our experience was primarily in industrial and electric bike controllers. There is a wide range of performance and features, and many are well below average. BLDC motors are current driven devices, the voltage determines acceleration and maximum speed, current delivers torque. The really capable controllers can generate speeds higher than the voltage would indicate at reduced torque by timing adjustments. Good luck with your project. I'm considering purchasing one of these lathes, if I come across a better controller I'll check back, but most of my applications are not too demanding.

Since you got a better controller already, is there a motor that matches the controller that is suitable? I should go look at your other thread, will do that now and stop posting in this thread.

[maxspongebob]

I made another modification to the lathe. I replaced the discrete interface cards with a universal BOB for the ESS controller. Here is the thread for the new BOB.
https://www.cnczone.com/forums/gener...ml#post2507344

[maxspongebob]

I wanted to turn threads on a gun barrel and needed a spider nut to keep the barrel centered in the spindle. What I made is a new nut for the spindle. Here it is. Some brass screws will finish it up.

[maxspongebob]

I made a depth stop for the spindle. It screws into the spider nut and is secured with the brass knobs.