I am thinking of building my own power feed for my PM-727m mill, What I am wondering what speed range would be realistic? My thought right now would be in the 1 to 4 inches per minute range. Rapid would be? Or am I better off buying a power feed? I would like something that hangs off the end of the table less then what I've seen commercially available. Any input from anyone who has built one would greatly be appreciated!
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X axis power feed question
- Thread starter tweinke
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- Jun 12, 2014
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- 4,815
I built an X axis power feed for a bench top mill using an AC 10-90Hz (20-175 RPM) Bodine gearmotor with a direct coupling to the X drive years ago, using a VFD drive it would have a speed range on that mill of around 3-30 IPM, usual milling I would want a range of around 3-10 IPM, high speed button was 30 IPM. Wish it would have gone a bit lower, also not much power at low speeds but good enough for the size machine. Most factory axis drives use a DC motor have a usable RPM of around 4-160 RPM with a bit more torque/Hp so a usable machining speed range of around 2-20 IPM, high speed button is probably around 20-40 IPM, but this depends on the pitch of your leadscrew ( work back from the rated motor shaft RPMs). So you are in the ballpark, but for aluminum I usually machine in the 8-10IPM, steel 1-4IPM but depends on a lot of different factors. High speed on your size machine I would be fine with 20 IPM.
Not sure you can get away with something that hangs less off the table and usually need some form of clutch disengagement. A cogged belt design to a stepper motor or DC motor may be the most compact. Different approaches, some people use windshield wiper motors. I used a jog joystick with a speed pot for left right and had separate high speed buttons for either direction independent of the joystick. Also would add limit travel stops.
AC motor drive and servo motor
Not sure you can get away with something that hangs less off the table and usually need some form of clutch disengagement. A cogged belt design to a stepper motor or DC motor may be the most compact. Different approaches, some people use windshield wiper motors. I used a jog joystick with a speed pot for left right and had separate high speed buttons for either direction independent of the joystick. Also would add limit travel stops.
AC motor drive and servo motor
MKSJ that was absolutely what I was hoping to get in a reply. The DC motors I have available to me that appear to be powerful enough would either run too slow for any rapid travel or too fast for cutting even if geared down. I do have three stepper motors think they are 34 size off my deCNC'ed Shoptask. Don't have functional driver for them though. Now I'm not sure which way to go, buy or build.