Spindle motor options

[awetmore]

I bought a used Taig 2019 CNC.

The spindle motor on my mill is not the "upgraded" 1/4hp motor that they use now. It is a 1/8hp 3000 rpm Dayton motor. I've already had the bit bog down a couple of times while doing spiral drilling (I'll lower the feet rates to avoid that).

I'm wondering what options I should consider for a replacement motor. If I go with a DC motor how hard is it to add speed control to my mill? Is there an aftermarket AC motor which is high quality and 1/4hp, but less expensive than the ~$110 that I can get from Taig.

Is this the simplest option for going to a DC motor? It is the ~$100 motor from Penn Industries.
http://sites.google.com/site/davescl...ovariablespeed

[awetmore]

I forgot to ask the most important question. Does the Taig mill motor mount plate have a standard hole pattern? The Dayton motor on my mill is listed as "non-standard NEMA" on the Grainger website. If not it is easy enough to make a new one.

[Lynn Livings]

Personally, I would be leery of the PSI motor and controller. Why? Because I bought that upgrade kit for my Delta Midi and the motor quit (open rotor) about 1 month after upgrade. After 3 attempts to get PSI to talk to me about it, I replaced it myself with a similarly rated motor from Surplus Center. It worked for about another 2 months and then the controller fried (open regulator). At that point, I threw it all in a box.
I also own a Taig lathe and mill, and have upgraded both to DC motors with speed controls. Both setups, although different, were purchased through Surplus Center about a year apart. Both setups are still working 2 years after the last upgrade (lathe has been going for 3yrs) and I have had zero problems with either. The lathe got a replacement 1hp motor and the mill got a 2.5 hp motor, although you can really not depend on the ratings of either motor.
My advise is to research your planned upgrade as much as possible and buy good parts. Good parts do not come real cheap; trust me I've tried it. But, you can find good deals if you know what you want and seek it out.
Good Luck!

Lynn

[Al_The_Man]

About the only option for AC 1 phase is a Universal motor and Triac controller, but I would not recommend it as a first choice.
The better bet would maybe look for a suitable fairly high grade DC motor or a servo motor and use a KB or Baldor SCR drive, these operate across either 120vac or 240vac 1 phase in for either a 90vdc or 180vdc motor.
The motor controllers are cheap on ebay, or even new if the open chassis style as these can be installed in your own enclosure and save a few $'s.
The set up in the link looks reasonably priced.
Al.

[awerby]

It's more expensive than the Penn State thing, but it might last longer. It's a nice, light 1/2 HP DC motor with a variable-speed controller, and I've adapted them to the Taig for foreign customers (since they can run on 220v 50hz power). You'd need to redrill the Taig mounting plate and bush out the shaft to fit Taig's 1/2" pulley, but it's not that big a deal to do.

Andrew Werby
www.computersculpture.com

[awetmore]

Thanks for the idea Andrew. I didn't know that Sherline used a DC motor. Does it maintain good torque even at low speeds? It sounds like a good option for me to consider.

[awerby]

but it won't be as strong as the standard Taig motor at low speeds. Any time you reduce speed electrically instead of with pulleys, you don't get the torque-multiplication effect that trades speed for torque, although DC motors have much better torque at low speeds than equivalent AC-DC universal motors run through a speed control. But that said, you can run it at about half-speed and use the pulleys for the rest of your speed reduction, which will allow you to take advantage of torque-multiplication. Just don't try to do it all with the dial, and it should work fine.

Andrew Werby
www.computersculpture.com