Variable speed drill press

[Arzach]

I picked up a free working Powerkraft drill press, then killed it.
Can it be fixed?

The scene: Found in a garage, the previous owner said it wouldn’t turn on.
After I got it home and removed the front panel, I discovered a simple mechanical lockout. And after removing that the drill fired right up.

The trouble: With the panel off, I grabbed the air compressor to blow out decades of sawdust. I hadn’t unplugged the drill, and the metal tip of my air hose shorted the control panel.

The solution? It’s a variable motor, I want to bypass the built-in controller and mount an external version. I see them from $20 fan controllers to $$$$ lathe controllers. How do I choose?

 

[whateg01]

Looks like it's a DC motor so depending on the voltage there are various ways to drive it. Need more info on the motor itself.

 

[Firebrick43]

I picked up a free working Powerkraft drill press, then killed it.
Can it be fixed?

The scene: Found in a garage, the previous owner said it wouldn’t turn on.
After I got it home and removed the front panel, I discovered a simple mechanical lockout. And after removing that the drill fired right up.

The trouble: With the panel off, I grabbed the air compressor to blow out decades of sawdust. I hadn’t unplugged the drill, and the metal tip of my air hose shorted the control panel.

The solution? It’s a variable motor, I want to bypass the built-in controller and mount an external version. I see them from $20 fan controllers to $$$$ lathe controllers. How do I choose?

That appears to be a universal motor. They will run on DC and AC and need some method so they don't overspeed. Who knows what Monkey wards contractor used, as they didn't give a circuit board diagram. It should not be used with modern DC and VFD controllers.

 

[Arzach]

There are no markings on the motor at all. At this point I hesitate to disassemble further. There is a crude wiring diagram and switch with some markings.

 

[Arzach]

What about something like the MLCS-9420?
Am I correct in thinking that with a switch rated for 17amp, a 20amp controller would be more appropriate than 15amp?
Can I bypass the original control by adding a male plug to the drill motor?
And/or is it difficulty to I keep the original on/off switch in the circuit?

MLCS-9420 on Amazon

 

[no704]

Open up the blown controller and see if you can identify fried components.

 

[Lightning rod]

this vintage of universal motor control would use a fairly simple Triac
control circuit. Like no704 said. lets see the circuit board
It should look similar to this

Triac speed control for universal motors

Electric Motors -- Fundamentals and Control

www.industrial-electronics.com

 

[bubinga]

Open up the blown controller and see if you can identify fried components.

Yes I was careless one time and fried a mc-60 control board I fried part of the printed circuit board and was able to solder a piece of wire across it.

 

[CCMark]

I have the same drill press with a blown circuit board. As much as I would like to just repair it I wouldn’t know where to begin. I bought a K&B speed control but it only has 2 wires . I called them and they said it wouldn’t work. Can someone suggest one and how would I connect it to the 3 wires coming out of the Motor Black Red and White(assume white is neutral) ?

 

[bubinga]

I have the same drill press with a blown circuit board. As much as I would like to just repair it I wouldn’t know where to begin. I bought a K&B speed control but it only has 2 wires . I called them and they said it wouldn’t work. Can someone suggest one and how would I connect it to the 3 wires coming out of the Motor Black Red and White(assume white is neutral) ?

Black and red on the motor is usually your variable voltage input the white you could probably disregard.
Then you would just need 110 volt in, and a three wire potentiometer wired in there's usually a wiring diagram with these boards, something like wiper is the center one of the pot and the two end ones go to the other two terminals if it works opposite as expected in other words turn into the right and it slows down you switch the two and ones. I'm going to post this and then let me see if I can find it on eBay the board I used heck I might even have one around here I could sell you reasonable but only God knows where it's at right now.
You can usually wire a reverse into these boards too it's a single pole double throw switch it's not hard.

 

[bubinga]

Black and red on the motor is usually your variable voltage input the white you could probably disregard.
Then you would just need 110 volt in, and a three wire potentiometer wired in there's usually a wiring diagram with these boards, something like wiper is the center one of the pot and the two end ones go to the other two terminals if it works opposite as expected in other words turn into the right and it slows down you switch the two and ones. I'm going to post this and then let me see if I can find it on eBay the board I used heck I might even have one around here I could sell you reasonable but only God knows where it's at right now.
You can usually wire a reverse into these boards too it's a single pole double throw switch it's not hard.

I'm sorry if I remember right it's double pole double throw switch to wire up a reversible feature, and you kind of have to Kris Kross the wires on the switch and tap off the two center ones....wires and wire it up I have a diagram around here somewhere or I can find you one.
This one would work.
This is switchable between 220 input or 120 input there's a slider switch on there.
You might even be able to find one cheaper, second hand or open box or otherwise. You have to read good on there I think you need to purchase a resistor too that goes in there.
If you want to try a board like this I can help you wire it up.
You would have to buy a 5 k potentiometer for your speed control and then maybe a little workbox to tidy everything up.

KB Electronics KBIC-240DS 9423M Drive, DC, 120-240V AC,12A, Chassis | eBay

Find many great new & used options and get the best deals for KB Electronics KBIC-240DS 9423M Drive, DC, 120-240V AC,12A, Chassis at the best online prices at eBay! Free shipping for many products!

www.ebay.com

 

[bubinga]

If I'm remembering right also there is a kbic 120 that is 120 volts only input which would probably be a little cheaper but the one above would work as well.

 

[CCMark]

Would this be the one that's cheaper?


https://www.ebay.com/itm/4044082065...hRanker&brand=KB&_trksid=p4429486.c101224.m-1

Would the existing 3 wire Potentiometer work. Also would the original resistor that is connected to the black wire separate from the board work? Pics below

KBWC-115K (H9016), 15.0 Amps @ 120 Vac, Wall Mount, AC Fan Motor Control H9016

This is what I already purchased and KB tech said it would not work

 

[CCMark]

This is the existing board and Resistor.

 

[dogdog]

There are two different controls dependents on the motor. Instead of guessing maybe put a meter on it and test the voltage to the motor if it is ac or dc.

It looks like it have a brush but…. It could be a ac universal motor. If it has a permanent magnet then it would be dc motor.

If it is an ac universal motor. It might be better to drive it with a triac base controller.

If it is a dc motor then a pwm controller might be better.

*just saying know what you are getting into first might be easier to find the controller you needed

 

[bubinga]

Yeah gee I'm sorry maybe your motor is different the board that I link to would be basically proprietary to a treadmill type DC motor.
Has stated above you need to see what kind of motor that is and everything and then maybe the felllow above can help you further.
The potentiometer you have could probably be used if that board is suitable for your application.
Sorry I couldn't give a more concrete answer.

 

[Packard V8]

Randomly, there's one of those on craigslist here:

"Needs fuse and is currently not working. Handyman could probably fix easy and get it running. $20 must pick up." Yeah, sure, those solid state fuses are a piece of cake.

jack vines

 

[CCMark]

Well even more confused then when I started. Don’t see a fuse on the circuit board. Got it to work putting the black straight to power. But afraid I’ll fry it. But I guess its a universal AC motor since it worked. I can’t imagine that board acts as a transformer