dc motor for delta rockwell drill press

[bagged89s10]

I have the opportunity to get this this dc motor for a good price. 90v baldor 3/4hp, 1750rpm.



it should bolt right up to my drill press. will it have enough torque and what do I need to control it? looking for an easy solution that looks good. Does a dc motor offer better low rpm HP than a 3 phase motor with vfd? I want to mount it on my delta rockwell drill press.

 

[bagged89s10]

well I found this video by mr pete which I forgot i watched before. It happens that he used the same motor. I still need to source the parts I need to control it without breaking the bank.

 

[Packard V8]

I still need to source the parts I need to control it without breaking the bank.

All the DC motor control parts you need are found in "Free treadmill-U-haul it." Of course, that assumes you'll be able to recognize them, strip them out and re-board them.

jack vines

 

[tool_scrounge]

Just buy a industrial grade used DC motor drive (Minarik, Dart, KB Electronics) off of ebay. I like the packaged ones (NEMA 1). This one drives a 1/2 HP 1725 RPM motor on a vintage Craftsman 15" drill press just fine.

 

[wga]

That is a permanent magnet DC motor. So only two wires to connect to a control. It will operate from a DC motor control as Tool Scrounge mentioned. 110 VAC or 220 VAC single phase input. The control should have a method to select either input voltage. And a select 90 VDC or 180VDC armature voltage. This one is 90 VDC. There are several industrial brands out there too - SECO, Boston Gear, Reliance, and the others previously mentioned. Should be a 5/8" shaft on the motor. These work great for wood turning as well, usually need more HP.

 

[wga]

Just re read your post, as far as motor speed vs torque - DC motors are constant torque
so you should get good low speed RPM control. It might want to bog down. On the better higher cost DC motor controls, you can mess with the current limit and get some more amps.
The newer VFD's and AC motors are close in both cost and performance to DC drives. So That is why the DC's are going away. And now with PMSM permanent magnet synchronous AC motors, you get the torque and speed control, plus energy savings.
This gets pricey -

 

[FlyingLow]

I got a free treadmill that didn't work. Had a 1.5 hp motor and a stand alone DC power supply. I'm far from an electrical genius but managed to figure out how to hook up AC power and add a $10 adjustable potentiometer. It needed a fuse on the ciurcit board which is why it didn't work. I built an aluminum box to contain the ciurcit board and switches. I'm away at work until tomorrow but I can post up some pictures then. I still have to install everything.

If you don't mind spending some money though I would scrounge a 3 phase motor and buy a VFD. From what I've learned it will have much better torque at low rpm than the DC setup.

 

[FlyingLow]

Here's some pictures of my board and potentiometer. It is probably the cheapest way to go.

 

[Super Mech]

All the DC motor control parts you need are found in "Free treadmill-U-haul it." Of course, that assumes you'll be able to recognize them, strip them out and re-board them.

jack vines

Agreed. I took a motor and the needed parts with it out of a treadmill to power a small atlas lathe years ago. Google and YouTube have info on what you need and how to wire it. It wasn’t difficult.

 

[marinusdees]

I have a Craftsman floor model powered by a DC 1hp motor. Used it for years, not industrial use. I power it with a 10 amp rotary dimmer run through a full wave bridge rectifier. This is stone age technology, but it works. The motor slows down under load, but the rotary dimmer allows me to increase power as needed. I added a polarity reversing switch to allow me to reverse the press. Just for kicks I added a tachometer. All this stuff is available on ebay.