Motor for power feed on milling machine?

[Dudemanrod]

I was wondering if I could build a power feed with this motor it's a Bonfiglioli BN-63 A4 it's a gear motor I think and I'm not familiar with this type of motor 100 or so rpm. Itscca 3 phase so bad would be a must. Is it possible? It looks like a stout little motor.

 

[benmychree]

Dang, I think I just saw that motor just lately!

 

[mksj]

I used a Bodine gear motor of a similar kW (130 RPM) for an X drive driven by a VFD. Worked well for a smaller mill on the X axis. I used a direct drive coupler, the gearbox/motor turned easily with no power applied to the motor. Not sure on the right angle drives if the shaft will rotate w/o power to the motor. I used both momentary and a jogstick switches for feed direction with a speed pot in a small control box. Also added limit switches for travel, used 2 wire VFD motor control.

 

[Dudemanrod]

Thanks mk this motor won't turn without power so I I guess you you have to uncoupled it? The mill is a rf-30

 

[talvare]

Thanks mk this motor won't turn without power so I I guess you you have to uncoupled it? The mill is a rf-30

I built a drive for the knee on my BP mill a few years ago and I fabricated a clutch mechanism for it so that the drive could be un-coupled as well as adjusting the "slip" to control the available torque. Couple of photos attached.

 

[Dudemanrod]

Nice job Ted that looks awsome. Thanks for the photos it looks like my motor would work.

 

[Silverbullet]

I saw a YouTube where he used a power wheelchair motor . They have a cut off from the drive to freewheel , and with dc it's easy reverse and a speed pot . Those are quite strong and have long life. Just adding a thought.

 

[mksj]

Depending on the motor type and gearing, you may need some form of clutch system which is typical in most factory drives. I looked into elector-mechanical type clutches as I did not want to futz with having to engage/disengage a manual clutch/ belt/chain drives in addition to pushing drive buttons. I was able to pick up an inexpensive Bodine 240VAC 3 pahse gear motor and the VFD ran about $100. The type of gears used in this reduction drive allows the motor to turn without power and with an AC motor there are no issues with regeneration back feeding the control system and damaging the electronics. Below is the feed on the right with a direct drive flex coupler connecting the motor shaft, on the left is the control pod with Jog stick, momentary high speed jog buttons (bypassed the speed pot) and speed control knob. I had no shortage of drive power, only down side is a very slow feed rates for long periods would trip the VFD overload. I recommend limit switches so you do not damage anything.

At the end of the day you need to factor in that although the motor may be inexpensive the additional components to get it all to work and the complexity may not be worth it at the end of the day. In my case there were no off the shelf drives, so I made my own X and Z drives. Really a time saver with when doing a lot of repetitive work.

 

[Dudemanrod]

Thank you for giving me a reality check before I got into it. I'm thinking I'll save up and go the Chinese route and save money and keep my sanity. A little to much engineering for me right now I just got into this so I'm better off keeping it simple.