# Treadmill Motor Conversion On A Walker Turner Drill Press



## mattthemuppet2

alright, next project on the list - adding a variable speed treadmill motor and tach to my WT drill press which also doubles as a sort of mill. It currently has a 1/3hp motor with 5 step motor>intermediate>spindle pulleys to give 250-900rpm and 3000-5000rpm. Changing belts in the lower range isn't a major deal, but it's enough of a hassle that I'm almost always using the wrong speed for something, and that gap in the middle is a huge pain.

I got a 1.5hp treadmill motor and MC40 controller from a treadmill our neighbours threw out and it's been on my list of things to do since the summer. I did this mod to my Atlas 618 lathe with a motor from jpfabricator which is awesome, so hopefully this one should be relatively smooth sailing.

One thing I want to do differently this time is to use the flywheel/fan that came with the motor. I'll need some way of securing it to the motor shaft (1/2-13 LH thread) and I'll have to add a V pulley to it, but that should still be easier than adding a bespoke fan like I did with the lathe motor.

First step, 1/2in mandrel to bore out a spare V pulley. 1/2" piece of mystery steel, countersunk, drilled and tapped for 10-32 and slit with a hacksaw. I tried my slitting saw but the material just laughed at it.
	

		
			
		

		
	



pulley mounted up on the mandrel in my collet chuck. I used the smallest pulley with the biggest boss that I had, some garage sale find


lots of nasty CI later, it's bored out to 1.001in and the outside is tarted up.



next, make a 1/2-13 LH threaded mandrel to mount the flywheel to so I can turn the OD of the multi-V-rib pulley down to 1". Hopefully later today or tomorrow.


----------



## mattthemuppet2

well badgers, I should have stopped while I was ahead. Turned down a piece of random steel stock until it was true, then turned down the end for the OD of the threads. Dumb ass that I am, I forgot to divide the difference between the stock at the last measurement and the target size by two, so ended up with the piece at the thread minor diameter. GRR! Before I threw a fit, I realised that the small end now fits in my collet chuck, so I chucked up the small end and left it at that. 2nd try tomorrow most likely.


----------



## donthack

mattthemuppet said:


> alright, next project on the list - adding a variable speed treadmill motor and tach to my WT drill press which also doubles as a sort of mill. It currently has a 1/3hp motor with 5 step motor>intermediate>spindle pulleys to give 250-900rpm and 3000-5000rpm. Changing belts in the lower range isn't a major deal, but it's enough of a hassle that I'm almost always using the wrong speed for something, and that gap in the middle is a huge pain.
> 
> I got a 1.5hp treadmill motor and MC40 controller from a treadmill our neighbours threw out and it's been on my list of things to do since the summer. I did this mod to my Atlas 618 lathe with a motor from jpfabricator which is awesome, so hopefully this one should be relatively smooth sailing.
> 
> One thing I want to do differently this time is to use the flywheel/fan that came with the motor. I'll need some way of securing it to the motor shaft (1/2-13 LH thread) and I'll have to add a V pulley to it, but that should still be easier than adding a bespoke fan like I did with the lathe motor.
> 
> First step, 1/2in mandrel to bore out a spare V pulley. 1/2" piece of mystery steel, countersunk, drilled and tapped for 10-32 and slit with a hacksaw. I tried my slitting saw but the material just laughed at it.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> View attachment 119482
> 
> pulley mounted up on the mandrel in my collet chuck. I used the smallest pulley with the biggest boss that I had, some garage sale find
> View attachment 119483
> 
> lots of nasty CI later, it's bored out to 1.001in and the outside is tarted up.
> View attachment 119484
> 
> 
> next, make a 1/2-13 LH threaded mandrel to mount the flywheel to so I can turn the OD of the multi-V-rib pulley down to 1". Hopefully later today or tomorrow.


I love those treadmill upgrades!


----------



## mattthemuppet2

me too, I've been wanting to do this for over a year and wish I'd done it already everytime I use it!

Minor update - threaded the end of the arbor 1/2-13LH after a few adventures and the flywheel threads on nicely. Have to cut the register on the arbor for the bore of the flywheel and figure out somewhat of stopping it from spinning off, then I can start cutting the boss for the pulley.

can't wait to take a pic, it's a 7in flywheel on a 6in lathe, only _just_ clears the ways!


----------



## mattthemuppet2

finished up the arbor to hold the flywheel on the lathe. Threads were kind of crappy but the register is a tight fit and the flywheel has stayed on through a few cuts, so I'm pretty confident it won't unscrew.

not much clearance though 





have to pause this for a bit as the spindle pulley bushings were replaced by a previous owner and machined off center which is causing a lot of vibration and finish problems, so I'll have to replace those before continuing. Really don't want to screw this up!


----------



## mattthemuppet2

made a lot of progress 

turning down the flywheel stub



overshot and ended up with a tight slip fit instead of a press fit, so had to use a set screw instead




drilled through for a set screw to bear on the motor shaft (ground a divot for the set screw in the threads)





center drilling the motor shaft so I could turn the pulley and flywheel true





balancing the flywheel on my DIY balancing jig. It was a long way out of balance!





back together again 



currently making an adapter plate so I can bolt it to my drill press motor plate


----------



## mattthemuppet2

made an adapter plate out of a piece of alu scrap from my pile



I was pretty pleased by the milling - came out ok considering it's a drill press. Still desperately want a mill though.



mounting bolts drilled and attached to the motor



next up, electronics!


----------



## mattthemuppet2

making progress on the control box aaaaand blew up a couple of components on the drive 






adapter for the SCRs to use the case as a heatsink



in the box, in happier times..



blown diodes, not that it was working beforehand. Lots of troubleshooting ahead, although at some point it might be worth just buying a newer board.


----------



## easttex

That's a pretty rough looking PCB.  Will you be able to salvage it?

Sent from my SAMSUNG-SM-G900A using Tapatalk


----------



## John Hasler

easttex said:


> That's a pretty rough looking PCB.  Will you be able to salvage it?
> 
> Sent from my SAMSUNG-SM-G900A using Tapatalk


Doesn't look like he smoked anything but the diodes.   I've repaired worse.


----------



## mattthemuppet2

easttex said:


> That's a pretty rough looking PCB.  Will you be able to salvage it?
> 
> Sent from my SAMSUNG-SM-G900A using Tapatalk



it's pretty grotty, but most boards from old treadmills are pretty scummy  John's helping me troubleshoot it, so fingers crossed. I have a couple of diodes I can swap in, but I want to figure out what went wrong first. The annoying thing is that I can't remember if this board or the one that I put in my lathe control box was the one I pulled from a working treadmill. I got them both last summer and I've forgotten a lot since then!



John Hasler said:


> Doesn't look like he smoked anything but the diodes.   I've repaired worse.



fingers crossed! Not just for the cost of replacing it, but also the time fitting it to the case. These MC-40/60 drives are pretty compact.


----------



## easttex

mattthemuppet said:


> it's pretty grotty, but most boards from old treadmills are pretty scummy  John's helping me troubleshoot it, so fingers crossed. I have a couple of diodes I can swap in, but I want to figure out what went wrong first. The annoying thing is that I can't remember if this board or the one that I put in my lathe control box was the one I pulled from a working treadmill. I got them both last summer and I've forgotten a lot since then!



Right on man!  I'm following this thread with much interest!

Sent from my SAMSUNG-SM-G900A using Tapatalk


----------



## mattthemuppet2

thanks! It's all fixed, at least temporarily. Ordered some proper sized fuses and waiting to hear back about the suitability of the diodes I swapped in, but it ran up to full speed with no problems. No major vibrations, although at 4500rpm it looked (and sounded) like it wanted to take off


----------



## mattthemuppet2

well, it's not fixed as it doesn't work again  Just bought a new controller instead of trying to figure out what's wrong with it.

Finished the front plate and all the wiring that I can do for now. It'll be easier to finish all the box -> front panel connections once the controller board is in place.





made a knock for the speed control and while I was at it, for an LED lamp I made for my wife a while back.


----------



## mattthemuppet2

alright, all finished! The new board arrives and I was too excited to wait until the new fuses arrived, so I pulled the old motor off the drill press and put the new set up on.

bottom half before joining. It's fairly crowded in there. Wire on the bottom right is for the tach head, black and red wires at the top left are AC wires for the tach power supply. Both those wires and the power wires for the sockets near the motor are tapped into the AC wires downstream of the main switch on the left.



back of the front panel. The DC + and - wires come off the top two poles of the reversing switch in the middle - the 2 middle wires come from the board. Board power switch is on the bottom left, tach power supply (120VAC -> 9VDC) is top left, tach is top right and speed pot is bottom right



I was just JUST able to plug the pot wires onto their posts (MC40 board is laid out opposite to the MC65 on my lathe). Then I realised that I still had to bolt the controller box to the drill press from the inside. That wasn't fun.



everything mounted up. Had to partially remove the clock spring to get to the bottom right screw on the controller box - doh!



close up of the motor and the socket box. There's enough movement in the original motor mount slots to access the top to pulleys of the intermediate pulley, which is really neat. Most likely it'll be left in the top one, just put it in the 2nd from top because it was easier for now.
Socket is wired and grounded to the main box switch, so turning off the box turns off the sockets, which I'm pretty chuffed about.



here it is, in all it's glory! Wire on the right is the tach reader head, pointing up at the underside of the spindle pulley where I glued a rare earth magnet. Worked fine in testing.



can't take it for a spin yet until the 10A fuses arrive. Trust me, I tried and immediately blew the 3A fuse (all I had in that size). Still, all the lights work and the tach works. Fuses should be here today, so I'll update the thread with speed ranges and first impressions. I'm super pleased that this is finally done!


----------



## mattthemuppet2

finally got a few niggles sorted out and gave it a run through the speeds. I can put the motor belt on one of 2 intermediate pulleys, I only tested on the larger one as I didn't think to try the others yet (you can see it on the smaller intermediate pulley above).

That gets me 3 low speeds:
50-400rpm
300-1000rpm
500-1600rpm

sounds like it's about to take off at the high end of the speed range! I've also ordered a choke to put on the DC line as I found that smoothed things out and reduced noise on my lathe.

I'll check out the high speed range when I get home later.


----------



## mattthemuppet2

had a bit of a diversion - new link belts, forward-reverse switch crapped the bed, took the low speed shaft apart (took me 3 years to figure out how!), made a carriage stop and finally checked out the high speed of this thing. get this, 4300rpm!!! low end of 1300rpm, so a nice range for wood or small bits. might have to add a heart sink to the case though, gets pretty warm at extended runs at full speed


----------



## John Hasler

That's not really a very wide range for a DC motor with closed-loop controll.  You should be able to get 10:1.


----------



## mattthemuppet2

that's for 30-100% of motor speed (going by the pot position). From experience with the one on the lathe, below 30% is fairly gutless. However, this is a more powerful motor (1.5 vs. 1hp) and the different type of cutting action may allow me to go lower on the dp than I can on the lathe. I'll see how it goes with use and report back.


----------



## John Hasler

mattthemuppet said:


> that's for 30-100% of motor speed (going by the pot position). From experience with the one on the lathe, below 30% is fairly gutless. However, this is a more powerful motor (1.5 vs. 1hp) and the different type of cutting action may allow me to go lower on the dp than I can on the lathe. I'll see how it goes with use and report back.


I'm getting a 10:1 useful speed range on my lathe but that's with a closed-loop controller.


----------



## mattthemuppet2

from memory that's a controller that you made yourself right? Or some non-treadmill based controller? I'm using an MC40 treadmill controller, which I'm pretty sure isn't closed loop. Either way, I'm happy and that's all that counts


----------



## mattthemuppet2

just to (almost) complete the story, I added the choke I got off eBay to the motor. Runs much quieter and smoother now, less speed oscillation which is nice.





the reason why it's not completely finished is that I need to add the new F/R switch that arrived today, as the cheapo eBay one crapped the bed. this one is a decent brand and rated at 20A/125V, so that should do the trick. I've been missing my "start at previous speed" function that the switch gives me


----------



## Ulma Doctor

looks great Matt!
very nice use of materials, great project!!!


----------



## John Hasler

mattthemuppet said:


> from memory that's a controller that you made yourself right?


No, it's the one that came with the treadmill.  I made minor modifications.  One of these days I'll finish the tach and post the project here.

The controller I made myself is on the knee drive on my mill.  I'm not satisfied with the result, though.  The controller works fine but the 1/4 HP electric drill motor is too feeble.


----------



## mattthemuppet2

ah, gotcha John. got my wires crossed  with some more use and the choke on the motor line I've been using the 2nd fastest pulley from 300rpm to 2200rpm without any problems. dunno if it works better than the one on the lathe because it's a bigger motor or because the drill press/ mill is more forgiving.  can't see myself using the other pulley ratios other than for very small cutters or large drills/ hole saws. haven't done any work with steel yet though, but i did run a 1/2in router bit through some wood this evening at full speed, which was fun.

thanks Mike, it's been on the cards since Christmas and I've been looking forward to it for ages! it's every bit as great as I'd hoped!


----------



## hman

Matt -

On June 2 you posted, "I've been missing my 'start at previous speed' function that the switch gives me."  It's not clear, but did you get this working again?  If not, you might want to do what I did when I converted a drill press to use a treadmill motor.  By adding a simple on-off switch to the center wire of the pot, you can get  "start at previous speed."  I was lucky enough to find a pot with a push-pull on-off function right on the knob.

My only remaining gripe about the motor and flywheel is that it spins a LONG time after I shot it off.  I'm planning to scab on some kind of brake band around the flywheel.


----------



## markba633csi

Matt are you going to part with the WT power switch? I'm looking for one. 
Mark S.


----------



## Ulma Doctor

markba633csi said:


> Matt are you going to part with the WT power switch? I'm looking for one.
> Mark S.


matt has been banned, you'll not likely get a response.


----------



## John Hasler

Ulma Doctor said:


> matt has been banned


Why?


----------



## markba633csi

Too bad, any particular offense you can share?
MS


----------



## Ulma Doctor

against the rules of this forum, he stated his opinion of a staff member on another forum.


----------



## markba633csi

critisized not praised, I take it.  Nuff said. 
MS


----------



## John Hasler

Ulma Doctor said:


> against the rules of this forum, he stated his opinion of a staff member on another forum.





Ulma Doctor said:


> he stated his opinion of a staff member on another forum.


That's enough.  Remove my account.


----------



## minsk

mattthemuppet2 said:


> well, it's not fixed as it doesn't work again  Just bought a new controller instead of trying to figure out what's wrong with it.
> 
> Finished the front plate and all the wiring that I can do for now. It'll be easier to finish all the box -> front panel connections once the controller board is in place.
> View attachment 129576
> View attachment 129577
> View attachment 129578
> 
> 
> made a knock for the speed control and while I was at it, for an LED lamp I made for my wife a while back.
> View attachment 129579




loove this panel. nice build sir. just scored and mc-45/45 for free  . now... do i use it on my 6" atlas lathe or my delta drill press.... real world problems


----------



## mattthemuppet2

I'd put one on your drill press first as you'll get the most benefit from the speed changes, plus changing pulleys on the Atlas isn't as much of a chore as it typically is on a drill press. Quite often I'll drill, countersink and tap on the drill press just by changing the speed from ~1000rpm for drilling down to ~100rpm for tapping. In fact, the only time I've changed which pulley the belts are on are when I've needed to drill big holes in steel or use small end mills in aluminium (when I was using this as a "mill"). The rest of the time the belt stays in the same pulleys whatever I'm doing.

that said, keep your eyes open on Craigslist and you'll see treadmills pop up for free every so often, then you can snag one for your lathe


----------



## minsk

i ordered my  display box...and board box...from digikey...all will be painted clausing blue of course..ill prolly do a video for my youtube channel.
have an a small led tach coming. stoked...drill press is def next.


----------



## middle.road

mattthemuppet2 said:


> .......................
> 
> that said, keep your eyes open on Craigslist and you'll see treadmills pop up for free every so often, then you can snag one for your lathe


Estate Sales on the last day are also a good source. 
Although during the past couple of months folks have been 'buying' them the first day. I wonder if it has something to do with New Year's resolutions?


----------

