Drill Press Modifications

[skeer]

So, here lately I've begun modding the 'el cheapo' DP I picked up a few months ago at the local salvage yard. Plans included: treadmill motor, RPM gauge, and work light (for now).
Yesterday's trip to the SY netted a very nice condition TM motor; 96vdc, 21A. I also came home with it's controller, just in case, and the 120V incline motor. Along with two other DC motors that were on the frame of one of those 'electric mobility' deals. Like the things you see at a grocery store from those with issues walking, and the controller for it.

So, turns out, the TM controller is not one of the easy older models you can just potentiometer-ize. It's an MC-2100-UW, meaning must have a pulse generator to control the motor speed. So to the drawing board/Google I went... found some threads here on GJ that led me to Youtube where i found a guy who'd designed a simple circuit using a pair of 555 timers. His site led me to an Amazon link for a cheap digital PWM controller.. which then led me to another guys YT channel who had used a cheap 120v motor speed controller and a fat FW rectifier.

So the last idea is the one I'm rolling with, I have a Controller, RPM gauge and an ABS project box on order.

So the over-aching idea is to mount a toggle for main power, power LED, relocated MSC potentiometer, and the RPM gauge in the enclosure. With a disassembled 120-12v wall-wart splitting off the toggle to power a 12v light that will be mounted underneath the head to shine down from behind the quill, onto the table.

I'm still on the prowl for a 1.810" OD steel pipe to replace the column and raise things up a bit. If I can get a longer column then I'll look at adding a rack and somehow rig up the incline motor to raise/lower the table.

 

[skeer]

The other two motors and controller I brought home (I just discovered) are for one of these: https://shoprider.com/products/power-chairs/streamer-sport

The motors themselves are 24vdc.. unknown amperage. The gear reduction is built into the end of the motor housing.. the workign end of the armature is nt ribbed or slotted but its threaded as such to mesh with a normally toothed(?) gear.

No idea what the rotational ratio is, the label ont he motor returned nothing when I searched for it. I have no idea what I could use these for. The Controller is listed here: https://mobilityequipmentforless.com/products/permobil-c300-d5067607-vr2-power-chair-control-module

Might just toss it on eBay, I found the tech manual for it last night and it doesn't seem to be anything useful outside of one of those chairs.

 

[LXCam]

Sounds like a project and it’ll be cool to see what you do. Also I’m thinking you might have better luck searching for a 46mm column instead of a 1.810

 

[skeer]

For anyone interested, the power chair motors are Shihlin/Eurton M19014619, I can't find that exact part number but it's almost identical to this one.
24vdc, ~4A unloaded and up to 20 loaded.
Each one has an electromagnetic brake on the brush end with a manual release lever. Again the mfg doesn't have this exact part number listed but it's identical this.
24vdc, 10.8W and 3N-m of force. I think I can find something to do with these...

 

[skeer]

So last night I found a video outlining how you can use a 6-pin toggle switch to control DC motor rotation direction. I tried it with my MM and the poles were indeed reversed. But, I guess I wanted to throw it here to ask if this is a smart way to handle it?
LINK HERE

Actually, it's exactly what this guys showing.. so yeah I guess it's a legit circuit method:

 

[skeer]

So last night I was mocking things up.. yesterday I was off so I had more time to spend on this. Anyway so using an old dimmer switch, I had everything the same as the motor tests before with two exceptions: This time I ran Line thru the motors temp switch and I had a main power switch. This switch was a 15A rocker, 4 pin so ohming it out the two tops connect to the two bottoms when flipped. Meaning I figure it was for both Line and Neutral.
So.. hooked it all up and flipped the rocker. The power led came on so that's good. Clicked the dimmer on (same dimmer I used during testing), this time however after making maybe 1/2 of a turn I heard the zap, saw and smelled the magic smoke. Immediately killed power.

So I'm not 100% positive where the smoke came from.. the temp sensor/switch itself still ohms through as do the motor coils. Granted I have no before resistance measurements to compare. However I did find that the power rocker switches internal contacts must've been a mess because out of 120v in, only about 82V were being passed through.

So removing it from the mix and going back to the dimmer only the next power up resulted in the dimmer itself popping. After inspecting the mosfet inside it exploded.

I'm confused as to why number one, the dimmer decided to go belly up. I wouldn't expect a lower voltage to cause problems but am I wrong in that? Maybe the frequency was affected?

 

[oldmachinenut]

I converted a bandsaw to DC using a treadmill motor(free) and a KBIC125 controller($60.00,ebay) It works very well.

 

[skeer]

Yeah I have a motor speed controller arriving today. I was just using the dimmer to test it with before I spent the $$ ordering the right things.

 

[skeer]

Hmm, well just received the SCR and I'm pretty sure it's bad. First off the case markings for the input/output screw termianls were reversed when compared to the pictures on Amazon. Trying both ways, gave me readings of 120vac straight through.. the potentiometer is apparently non-functional and just for looks, lol.
So now I gotta get a replacement. But luckily enough the board has a rectifier on it.. I was under the impression that I ordered an AC regulator, this guy should put out DC so that's nice.

 

[Packard V8]

I converted a bandsaw to DC using a treadmill motor(free) and a KBIC125 controller($60.00,ebay) It works very well.

After seeing prices for that controller between $60 and $125, maybe I'll just continue using the control panel off the treadmill. True, it's awkward, at 26" long, 6" high and 3" deep, lights up like the console of a starship cruiser; but on the wall it's out of the way, free, works perfectly and only needed the addition of a three-way switch to provide reverse. GJ shadetree at its best.

jack vines

 

[oldmachinenut]

I had a KBMG212 driving a Dayton 3/4 hp pm/dc motor on my Bridgeport. I also used the whole treadmill control panel for a while, I needed the mill part way through the conversion and it worked fine. I still haven’t put the permanent pot and switch box on it.

 

[skeer]

After seeing prices for that controller between $60 and $125, maybe I'll just continue using the control panel off the treadmill. True, it's awkward, at 26" long, 6" high and 3" deep, lights up like the console of a starship cruiser; but on the wall it's out of the way, free, works perfectly and only needed the addition of a three-way switch to provide reverse. GJ shadetree at its best.

jack vines

Yeah had this been one of the older styles that a typical potentiometer would work I'd have gone that route myself. I should not have cheapened out on a $14 regulator.

 

[skeer]

Ok so I thought I knew enough about electronics but I didn't.. learned something new yesterday. SCR's won't regulate output voltage until there's a load. I'd like to understand how but that might involve brain power and math that are above me, lol.
At any rate, using an old 80W light bulb I did verify that it works. Except now there's a new problem.

Last night I hooked it back up after testing with the bulb. Outlet -> scr -> rectifier -> motor. This time bypassing the blue wires for the temp switch and the DTDP toggle for rotation direction. Now though the SCR blows it's fuse and the motor never appears to get power or doesn't get enough to turn.
The motor windings measure almost 2ohms and there is continuity between the positive and negative wires. If this SCR really is rated for 4kW then I'd assume the 5A fuse would be big enough to handle the initial current bump.. especially when testing with the dimmer I never saw the current draw exceed 3.5A and even then it was only for half a second or so.

 

[skeer]

Alrighty, Well it's all done. I did end up having to buy a larger SCR (10kW) Drill works pretty damn good too, and it'll work better once I replace the 500k ohm pot with a 200k. But it turns on, the RPM gauge is about as accurate as $14 will buy but hey.. it's better than nothing lol.
The pulley on the motor is one I pulled off the alternator on our old '09 Tahoe. It was ribbed of course, ground a channel for the v-belt and it fits pretty tight. I will get back out there when the weathers better and drill/tap a hole for a set screw.

Once those are done then it's time to hunker down and source a column so it's not so ****** short.

https://imgur.com/a/5lwZA15

 

[Monza Harry]

Well after seeing your video, my idea will not help. My thought for extending that was be to add a riser block under the existing column flange. However that is one short Mo-Fo drill press! Maybe put this in your back pocket for another project/problem(?.) Harry

 

[Zeus36]

Here is one of my mods to a cheapo drill press found in a dumpster. Even had a keyless chuck:

 

[skeer]

Well after seeing your video, my idea will not help. My thought for extending that was be to add a riser block under the existing column flange. However that is one short Mo-Fo drill press! Maybe put this in your back pocket for another project/problem(?.) Harry

I thought about that myself.. the OD is such an odd ball size I doubt I could find it in an ID for a riser sleeve.

 

[Monza Harry]

skeer, Sorry, my explanation was a little thin. My thought was more to a fabbed block for that existing flange already on the column. Needs to be solid under the screws, (tubes etc.) tied into the OD of the riser. Harry

 

[skeer]

Oh no you are good. I’m also trying to think of that as well if I can’t source a column.

 

[skeer]

Has anyone tried coupling a TM motor to the spindle on a drill press? I saw the Nova King line at grizzly https://www.grizzly.com/products/teknatool-nova-viking-16-floor-model-drill-press-with-fence/t33237

I'd expect if these are direct coupled then they're using a coupler type with some shock absorption.