Introduction: Use a Treadmill DC Drive Motor and PWM Speed Controller for Powering Tools

Picture of Use a Treadmill DC Drive Motor and PWM Speed Controller for Powering Tools

Power tools such as Metal cutting mills and lathes, Drill presses, bandsaws, sanders and more may require .5HP to 2HP motors with the ability to fine tune the speed while maintaining torque.

Coincidentally most Treadmills use a 80-260 VDC motor with a suitable HP rating and a PWM motor speed controller to allow the user to change the belt speed and keep a good constant speed and torque while running on it.

There are Commercial DC Motor/PWM controllers available or you can build the PWM circuit from scratch and buy all the components seperately but you will spend a lot of time and money either way. All the parts you need are on the treadmill.

Tear your own apart or get one on Ebay.
(shameless self-promotion below)

Motor/controller combos on Ebay

Safety and Disclaimers- You should have some knowledge of electricity and the dangers of household current and know your abilities/inabilities. Serious injury may occur to you or others from use/misuse of these motor set-up. If you are in doubt DO NOT ATTEMPT. IT CAN KILL YOU. Any Crazy Ideas found here REQUIRE your testing. Your appliction and use of any ideas here are all on you and you agree I cannot be held liable. You equipment should have On/Off safety switches, Fuse protection, ground wires on your machine as required and your power source should have ground fault interupters, circuit breakers,properly grounded sockets and cords and always unplug equipment before tinkering and any other safety practise I am forgetting to mention.

Step 1: Motor Vid

Picture of Motor Vid

Testing the motor/controller

Step 2: The PWM Circuit Board

Picture of The PWM Circuit Board

For a complicated description of a treadmill PWM (Pulse-Width-Modulation) controller you can visit
You can visit wikipedia for a better definition of PWM.

But basically (as best I can understand) it's an efficient speed controlling circuit that pulses the Voltage and the width of the signal to the motor off and on thousands of times per second. This transfers more power to the load and wastes less power to heat than a resistive type speed controller.

PWM style controller Trim Pots- located near one of the edges of the board.Each Set for specific motor

MIN (Minimum speed-Touch if you dare) adjusting MIN Trimpot may affect MAX, may be necessary to adjust both until desired levels are achieved

MAX (Maximum speed-Touch if you dare) Note that MAX adjustment may affect MIN

IR COMP (Inrush compensation-Don't touch)Improves load regulation by providing minimal speed fluctuation due to changing loads. If the load presented to the motor does not vary substantially,the IR adjustment set at a minimum level. Excessive IR comp will cause control to become
unstable causing motor cogging.

CL (Current Limiting-Don't touch)The CL Trimpot sets the current which limits the maximum current to the motor. Also limits the AC line inrush current to a safe level during startup.

ACCEL (Acceleration Time Period, 0-full speed in seconds)I've never seen one on a treadmill circuit card, only on commercial PWM DC motor controllers. There must be something on the treadmill board that sets the time value..resistor perhaps?

Step 3: The Speed Pot

Picture of The Speed Pot

PWM circuits uses a Pot (Potentiometer)to adjust the speed from 0 RPM to Max RPM . The Potentiometer can be of the rotary type or linear sliding type. The potentiometer is usually rated 5 or 10K Ohms. Typically 0 Ohms is no movement and 10K Ohms is full speed (unless you have your Pot High and Low wires swapped...then it's visa versa). Keep in mind the motor may not even begin moving till 2 or 3 K Ohms (actual value varies) and you can't really start the pot at 2 or 3K Ohm position either because the treadmill motor controller requires 0 Ohms on start-up (Kind of annoying).

The Pot talks to the circuit board through 3 terminals usually marked High,Wiper and Low (or H,W,L).

Some controllers use a digital console to change the motor speed. You dont want to scroll through programmable selections, excercise routines and heart beat monitors just to change the motor speed on your lathe.
Solution: Throw it away and replace it with an appropriate Pot(usually 5 or 10K Ohm Pot). The digital console interfaces the PWM Circuit board the same way that The speed Pot does. through those 3 terminals (on some marked G O H or L W H and colored black, white and red or S1,S2,S3, colored Blue, Grey, Orange.

You should also use a switch for ON and OFF. The Pot is for speed control once the machine is running.

Step 4: Types of Treadmill Motors

Picture of Types of Treadmill Motors

I have seen 3 types of motors.

DC Permanent Magnet with PWM controller (Great for torque at all speeds).2 wires to the motor (Usually).

DC motor with Armature-voltage DC Motor Control. (Great for torque at all speeds).4 wires to the motor. 2 run to the shunt-field current , 2 run to the armature. Vary the voltage applied to the armature, vary the speed. Not all 4 wire motors are Armature Voltage controlled. Some have 2 wires that are part of a thermal protective circuit. The ones I have seen are usually both blue.

AC motors. (Probably not any better than the AC motor your'e thinking of replacing).Motors are running at a constant. Incorporates a special sliding pulley.Changing the belt speed is done manually-controlled with a cable that changes the size of the pulley's diameter. Larger motor pulley diameter faster belt speed, smaller pulley slower belt speed (I think).

The DC motors vary in size but most are Permanent Magnet,have brushes, a flywheel,and have either tapped holes or a bracket or flange welded to the case for mouting. They typically can range from 80-120VDC but as high as 260VDC. The HP's 1/2 to 3.5HP (treadmill duty rating), Upper end RPM 2500-6000, 5-20 Amps.

The Max RPM isn't as critical when you can adjust to any RPM within the range and keep a near constant torque.

You can reverse the direction on the DC motors by reversing the polarity. Simply swap the 2 motor wires (usually Black & White or Black & Red)at the terminals on the PWM circuit card. Remember if you reverse the direction of the motor you can't use the flywheel as it is. Because of left hand threads it could come off. Drill tap and set-screw the flywheel to the shaft

Step 5: Drive Pulleys and Belts

Picture of Drive Pulleys and Belts

Most treadmill motor flywheels serve also as the pulley. They fit a fancy flat belt with 5-10 "v" grooves. The driven pulley that mates with this belt originally drove the large roller that the treadmill belt rode on. Reusing the plastic roller pulley is near impossible. Very few motors actually come with the common Automotive 4L style belt pulley. Solution: Remove flywheel and replace with normal V-belt pulley. *If the flywheel you take off had fins for cooling the motor, replace it with either a blade mounted to the shaft or an externally powered fan*

Taking the flywheel off can be a pain. The flywheel are left-hand 4m thread and can really be cinched down or corroded onto the shaft. Chuck the flywheel end in a vise and turn the shaft on the opposing end Clock-wise and the flywheel may come off.

Some Motors don't have 2 shafts. The shaft on the brush side is usually hidden under the bearing housing. For the stubborn or single shaft motors I use a hacksaw and run the motor on low speed and use it like a metal lathe and saw the pulley through once or twice. It always comes off easily when you turn the nut into 3 thinner nuts rather than one wide nut. Just make sure you don't cut into the motor shaft. Eyeball it close and then test it by turning it with a pair of vise grips until you are through the threaded portion.

Or.... If you don't mind the flywheel...
You can use the motor(at a very low speed) as a metal lathe and carve a suitable groove to fit the belt of your choice. It can be a bit tricky (dangerous) as your cutting tool is not fixed. ** USE eye protection, gloves, faceshield etc.**
A rat tail file will work for a round belt or a small bastard file can carve a v shaped groove for the common automotive style belt.

Remember again- If you reverse the direction of the motor you can't use the flywheel as it is. Because of left hand threads it could come off. Drill tap and set-screw it.

Step 6: More Idiosyncrasies

Picture of More Idiosyncrasies

There are some small but solveable problems using these set-ups. I think a lot of these issues could be fixed with trim pot settings but the exact amount of adjustment and the values for each vary too much, are vague and unpublished or unknown to the average person. If you come up with better solutions PLEASE let me know so I can update them.

problem 1) Treadmill motors have a 3-4 pound fywheel. Engineers calculate the energy stored by spinning this heavy flywheel to obtain Horsepower ratings referred to as "Treadmill Duty Horsepower". Any quick changes in speed aren't noticed because of the kinetic energy still stored in the flywheel. Sometimes you can hear the motor totally turn off till the flywheel spools down and balances the motors RPM with the respective setting on the rheostat. If the load is restored or the speed setting raised above the motor's present speed, the motor turns right back on. Solution: remove the flywheel. Some of that kinetic energy will be stored in the piece of equipment you are powering but if not then some horsepower could be lost.

problem 2) When starting up a treadmill you wouldn't want it to start up at full speed while you are on it. If the rheostat is not set to the lower end of the resistance value the circuit will not start. Now you have the Motor/controller combo on your drill press or mill and it won't start because the rheostat is not set in the start position.
Solution: Turn the rheostat to the start position before turning on.

Step 7: My Treadmill Powered Tools

Picture of My Treadmill Powered Tools

This is my Drill press converted to a mill. I got it at the junkyard for $10. It had a bad AC motor. The Crossfeed table is from Enco and the new motor is off of a treadmill also from the junkyard. The motor and belts drive it just like the original motor did. It drills and mills fine. The treadmill motor mount was identical to the original AC motor mount. I experimented with the original 2 belts but quickly got rid of the extra belt and step pulley and went with one belt. There was no need for moving belts up and down the step pulley anymore. The motor keeps good torque at all speeds.

[ My Treadmill powered Mill/Drill]

(Future pics of Sewing machine mod will be here)
The machine is the 1940 style heavy duty leather machine and had its own 4 ft bench and a 50 LB friction clutch motor hooked up to a treadle. The machine and bench just would not fit in my garage. am fitting it with one of these set-ups and have tested it enough to know it will work. The foot control is off of a newer sewing machine that used an AC motor speed control circuit also utilizing a Pot. I tore out the rest of the circuit and replaced the Pot with the 10K Ohm Pot my treadmill motor speed control needed. Now I can operate the sewing machine in my living room like a normal portable machine. It has as much torque as the original clutch motor and will sew right up your arm.

Step 8: Motor Mount Styles

Picture of Motor Mount Styles

This is 4 of the styles I have found. All pictured are DC motors. All except the last one are the permanent magnet type. The lower left motor image has a mount almost identical to the mounts on the AC motors found on drillpresses and such.

Step 9: Foot Speed Control

Picture of Foot Speed Control

This is a sewing machine foot control that I modified to run a motor set-up I plan on powering an old industrial sewing machine with. The circuit inside was originally for controlling an AC motor so it is only good for mounting your potentiometer. Remove all the circuitry of the original controller (i.e. resistors, pot SCR's and such)and mount your speed Pot. It takes some adjustment of the placement but it can be done. I can now control the treadmill motor with my foot from a few RPM to full 4000 RPM.

Step 10: Schematics/Pics

Picture of Schematics/Pics

This is some Schematics and Pics I have collected. Most Treadmills have one taped to the plastic belly panel. If you have a schematic you would like to contribute email me. The PDF's download very slow but the detail is worth the wait so be patient. Just right click it and open in another window and check out the rest of the instructable while it downloads.

Step 11: Reader Submitted Contraptions

Picture of Reader Submitted Contraptions


kbsantosh1 (author)2017-10-27

I have a treadmill (ProfForm 385Ex) with MC-60 motor controller which runs uncontrollably. As soon as the power/safety switch is turned on the motor starts rotating and the belt starts fast (not crawls). The sliding potentiometer does not seem to impact slow speed but I can increase the speed with the potentiometer but cannot decrease it beyond a limit.

I unplugged all the 3 wires (high, wiper, slow) of the potentiometer and switched ON the power - the motor still runs at a certain constant speed (medium) without the poteniometer.

What could be wrong ? that the motor does not slow down or controllable by the pontetiometer for slow speeds? Thanks much for help.

SpinnerOfWood (author)2016-12-27

Ok ChrisL358 as stated in my reply to you I do have pictures now that I can post. I would appreciate any help I can get from anyone on how to wire all this mess up, motor, pot, toggle switch and maybe a digital read out somewhere to show speed.

The first 3 pics are of the actual speed controller board it's a very old board 1976 to be exact. If it were a MC60 0r a MC 2100 board the wiring would be much easier have Youtube vids for that. There are no markings to per say what kinda board it is other than a manufacturer number and the year on one of the pics. As you can see it's a mess.

The last 3 pics are the motor with the specs and the wiring, notice the middle wire connects to nothing as the 3rd pic shows have no idea what it goes to. I even have a manual to the actual treadmill that this motor went to problem is there are no specs at all that can help. Did a google search for specs on the board and motor and found nothing that could help, you can call Lifefitness and still no help for they change part numbers way to often so they really have no specs on the motor.

I am no electrician but do know basic stuff if anyone can help please let me know in "layman's" terms or LOL I'll get lost. Thanks

FredP40 (author)SpinnerOfWood2017-02-26

Two wires are + and - DC drive to the motor and should labeled as such on the board. Two wires to the motor are over temp sensor. Should be three wires or terminals labeled "H", "L", "W". These wires hook to a potentiometer to control speed. H wire goes to one side of the variable resistor, L goes to the other of the pot, W wire goes to the center or wiper terminal. 10K variable resistor should work good. A higher value may make more sensitive and lower may less sensitive to speed changes. Two wires attach to AC power to the hi-lo terminals or labeled AC.

FredP40 (author)2017-02-26

a DC motor can also be a generator. a spinning DC motor generates a current and voltage. The difference between applied power to the motor and generated power from the motor determines the motor drive. The controller measures the motor feedback to determine the speed of the motor. A variable resistor or circuit controls desired drive to the motor. The controller balances the applied drive and feedback signal to control drive to the motor attaining a more or less somewhat constant speed. The controller adds drive signal to maintain speed by applying more drive as needed up to the maximum drive available from the controller in maintaining constant speed. The feedback from the motor is somewhat out of phase from the controller drive which is how the controller determines the proper amount of applied drive signal.

turbobug made it! (author)2017-01-04

honey extractor made from tread mill

SpinnerOfWood (author)2016-11-27

First off thank you so very much for this article. I'm new here and realize this is a old article but hope I can get some answers.

I am looking to make my own large bowl woodturning lathe( here: and have searched tirelessly for information on building one on a budget. I have just a few questions and have some examples of a speed controller and motor I looking at on eBay.

1. Are treadmill motors capable of high torgue? Reason why I ask is I need a dc motor that can handle being able to turn large blanks for bowls.

2. Do you think this setup would work and this is just a example of the motor I plan on trying to buy or scrap one from a used treadmill.

3. I realize that using all the electronics from a treadmill to control the speed etc. would be cheaper but while this is a excellent article I am no genius at electronics. So this is the speed controller I am looking to buy

I have a speed controller on my old lathe that I modified also with a new motor but the thing was so complicated to figure out going from a 3 phase motor to 1 phase I had to hire a electrician to figure it out( trigonometry involved LOL hurt my brain)

Anyhow if anyone can help me here with answers I would greatly appreciate it.

ChrisL358 (author)SpinnerOfWood2016-12-25

1) Treadmills have excellent torque. Most electric motors develop close to full torque all the way from 0 RPM up.

2) You can often buy motor/controller "pairs" off ebay for treadmills, that supposedly just need to be connected together and work. I'm not fond of canabalizing PCBs like that, especially if you're going to put it into a dusty woodworking shop and use it for hours at a time. Most treadmill controllers have a startup delay, which could be a bit of a hazard/annoyance in a shop. I'm searching for a purpose-built separate DC drive now. The MC-60 and KBIC-120 look promising.

3) That speed controller is a VFD, VFDs are for AC (usually 3 phase) motors. It won't work with DC motors (most treadmill motors).

SpinnerOfWood (author)ChrisL3582016-12-27

Thank you Chris for you reply. I have learned all since I made the post such as the difference between VFD drives and DC drives. I was lucky to meet a guy on eBay that is a electrical engineer for a huge company out of New Jersey. He is helping me allot but has limited time so slow going for now.

I did buy the above treadmill motor and a separate treadmill speed control board. Problem I am facing at this time is figuring out how to wire the motor,pot, and toggle switch to the board I have. Reason why I went ahead and bought the motor and control board separately is I got a heckva deal on both from eBay, paid $60 for the motor and $12 for the speed control board. I seen the guy selling the combo rigs on eBay but #1 he had none rigged with a 3hp motor #2 prices anywhere from $125 to $145 so I think I got a better deal just have to figure out the wiring.

Right now typing this I am on my laptop so I have no pics of the speed control or motor on here. I do however have pics on my desktop and will post them so maybe I can get some help with the wiring. Give me some time and I will make a separate post. The board is ancient 1976 exact and has wires everywhere guy left them all on it not to mention it has the biggest capacitor I have ever seen on any of these treadmill boards. Anyhow give me a few and I'll post some pics.

mimstz (author)2016-11-03


I have a 4 wire AC powered treadmill motor and when i press start, the motor runs for 1-2seconds and then stop, after fully stoped in static position it can run again for 1-2sec... where can be the problem? In the motor? 4wire - 2blue , 1black and 1red. 2 blue wire are for AC power supply 220V . For what are black and red? Is PWM wait information from them?

Please help me!

Thank you?

dhenderson6 (author)mimstz2016-12-19

The problem you are experiencing it related to an additional sensor that is built into the circuitry of the treadmill's control panel. (I see this same behavior on the treadmill motor and panel that I just recently tore apart.)

Newer treadmills have a speed sensor (typically photo or magnetic) and either a magnet or disk with black/mirror stripes attached to the front roller. When the controller spins up the motor, it checks the speed sensor to see if the roller spins up as expected. If the controller detects no speed, it shuts the motor down. On many treadmills, the control panel also displays an error code. If so, you can google the code and confirm that this is the problem you are experiencing.

If this is what you are experiencing, the easiest fix is to move the spinning magnet or disk from the roller to the motor's shaft and set up the sensor to detect that rotation.

tpetersen3 (author)2014-08-26

So are these DC motors actually servos or not?
I am assuming there must be some kind of signal coming out of the motor to the control board if the motors turn on and off to maintain a set seed. At least with the 4-wire units, and the two wire I guess would have an internal circuit to adjust to speed.
Anybody know for sure?
I am trying to find an fordable servo to power a bench-top lathe and I require spindle feedback to the control software for treading.

Thanks for any guidance!!

jcobern (author)tpetersen32016-12-05

Stepper motors will do that good and they don't cost very much

you could use one for the main drive & one for the secondary drive

the software will keep they instep with each other

SexyWood (author)tpetersen32016-11-13

you have to use more than the control board and motor then. There is a magnet that sits on the end of the front roller. On mine it feeds back to the control board and shows the actual machine speed to adjust the voltage to maintain the correct rpm. I have never went that far to use one, so I cannot offer that advice. If you can read and understand the wiring schematic for your treadmill, you may be able to get it to work for you.

JeremyM175 (author)SexyWood2016-11-28

The one on the front roller has nothing to do with the motor. It just counts the rpms of the roller to convert how far you have walked and how fast you are running for the display. the two blue wire in the motor send the motor speed /load to the board to adjust voltage. They work very well I just converted a shopsmith mark 5 that had a dead motor over to a 2.5 hp treadmill motor. Makes the lathe and drill press a whole new machine. I would imagine my band saw will be able to go slow enough to cut metal now. But since i have 3 shopsmiths this one will be mostly for lathe or when I need to run large holesaws ext.

LazyH (author)tpetersen32016-02-22

Probably a late reply but the four wires typically are thermal protection and power. A lot of circuits use induction feedback to keep a constant speed. In other words, as the motor experiences a load, the induction of the windings change (can't remember if it increases or decreases) due to a force counteracting the magnetic field, there are some circuits that do this passively, like how a capacitor maintains a constant voltage (to an extent) despite brief changes in load or amount of power supplied, there are limits but it would keep a relatively constant velocity to between 10-20% of a goal rpm, depending on the circuit. But for a lathe, you would need some kind of encoder like UberNoober said. There are actually a few different designs ofencoders you can print on your computer and glue to the spindle pulley (don't go on the motor unless you have a chain or gear drive, since belts will slip), a pair of LED's reflect off the dark and light parts printed on the paper you glued, and a sensor placed in the right proximity to the led and encoder wheel will receive the signal allowing you to determine the position of the spindle. It's like a stepper though, in that if the software glitches or something your reading will be off by however many steps were missed, a professionally made servo would be the best way to correct for this and for a homemade kind you would need a multiphase synchronus AC motor (aka, most brushless dc motors) Hard and disk drive motors typically fit the bill, but since you're looking at treadmill motors I'm guessing you need power to the spindle? That's actually what I am looking for information on too and if you'd like I can keep you updated on what I find. I don't know if you're still working on yours, but I'm planning a cnc build with ball bearing linear ways and a tapered bearing spindle with a belt drive to a 2.9 HP treadmill motor.

UberNoober (author)tpetersen32014-12-28

These are not servos, and they do not have any sort of position or velocity feedback. It could be possible to add an encoder, resolver, tachometer, etc in order to get the feedback you want, but you would have to work that out to fit your specific system and needs.

jcobern (author)2016-12-05

No servo, just dc motor, unless yours is AC. the most of them are all the same. 4 wires. 2 are power (pos. & neg.) and the 2 (blue) ones are thermoprotector

( so it don't over heat ) the magnet on the pulley is just a RPM meter. (most of them) if the RPMs drop the controller don't compensate for it. I guess that would drive up cost. these motors will run on almost any voltage you feed it. I have one that runs on 220 dc. Most dc motors are like that. the ones that say that they'll go only in one direction, that's because the pulley is treaded on the shaft. if you remove the pulley, cut it to hold a keyway, then you can make it turn either direction

just reverse polarity..

jimmigrino (author)2016-10-23

good day, i would like to ask if i can tap an arduino in this kind of circuitry. and if possible. can you guide me somehow. TIA. :)

mifasystems (author)2016-10-17

Hello there! Great material, thank you for posting this.

This looks exactly what I have except that the circuit board . Where can I find a design to replace the board?some information related to our new informative <a href="">d.c. drives </a>

Rustycrate (author)mifasystems2016-10-21


I've been going down the same "rabbit hole"...tidbits of misinformation, and links that revert right back to using the treadmill power supply...The treadmill I have has push button control so no slide or rotary control which I have to have,plus the CB is about 8" long and the transformer is huge...

Anyhow, I'd like to build one myself but it seems not to be time or cost effective, so...Here is what I've found

90/180 VDC speed control with pot part# 11-2269 @$84.95...

It doesn't look too complicated so maybe get one to dissect and build another one from scratch...Least ways I'd probably learn something....

Good luck with your hunt....

KamaalS (author)2016-10-01

Hi please guide me in wiring 180v dc motor 5400 rpm. I rummaged it from a junkyard. I want to run it on 220 AC current. As iam a total novice about electronics, any effort to elaborate the steps would be deeply appreciated.

StefaniaR2 (author)2016-07-08

Plan9Customs made it! (author)2016-05-08

Used this to make a diy pitching machine for my son. Great stuff and thanks for sharing the info about the trim pot. It functioned great, but I just had it bolted to a old car wheel as the base, so height adjustment was a pain to adjust when the speed was changed. Also it would move a bit from vibration so the new stand and tweeks will take care of all those issues.

Doing a remake now. I'll post a finished picture when I get the wiring cleaned up & stand cemented in and in the cage.

lonoliver (author)Plan9Customs2016-06-21

Nice pitching machine. How did you connect the wheel to the motor shaft?

VanceC3 (author)2016-02-16

I wanted to make an e-bike using a treadmill dc motor. Is it possible if I hook it up with a lithium ion batteries for charging? will it work/.

cbsannino (author)2016-02-06

I like you instructable. I've been searching for a way to alter the control board of the treadmill I bought to convert my lathe to a DC variable speed motor. So far no joy but your instructable has moved the search along, a little. Thanks for a good post and is there anyway to communicate with you directly. You seem to know what you're talking about. Thanks

Alex0018 (author)2015-07-05

Hey, I could use some expertise here. My treadmills digital consol died and I want to use the treadmill but not spend $100+ on a new consol. I am able to increase and decrease the incline but can't get the tread to move. I will attach the voltage diagram, I made a pwm circuit and tried putting the output on the blue wire hoping it would start the motor but it did nothing. How can I make my Nordic track c2200 work again?

EL34xyz (author)Alex00182015-11-02

I made a simple 555 timer control box and set up a web page with the build info here. It creates a pulse and send it to the motor controller.

I also uploaded a you tube video of my controller in action

jaya8 (author)Alex00182015-08-04

We had a similar problem about a year ago. When I removed one of the tread motor brushes, it appeared to spring free. I suspect that it had gotten stuck in its housing. I removed it, inspected the spring, brush and and housing. Everything seemed fine. Re-installed the brush and it's been working fine ever since. Hope that helps.

RogerA6 (author)2015-08-24

Just what I've been looking for!

All I need now is to figure out how to mount the speed pot to the foot pedal.

I have a sewing machine foot pedal I can use.

Any advice? Much obliged.

arthorn (author)2015-07-06

This looks exactly what I have except that the circuit board is fried. Where can I find a design to replace the board?

liverdye (author)2015-07-01

Hello there! Great material, thank you for posting this.

Would I be able to adjust the potentiometer to a very slow speed (for the purpose of a conveyor belt) or will I face electrical/mechanical issues with the other components in the treadmill's circuit?

I appreciate any help!

liverdye (author)liverdye2015-07-01

One more thing, I'm assuming that it would be better to find an older treadmill because it would be easier to take apart. Do you have any other recommendations in regards to other things I should keep in mind while shopping around?


Soki DaB (author)2015-06-19

Soki DaB (author)2015-06-19

matas1 (author)2015-03-18

well, for rpm, you want it on the spindle or on the chuck, anyways

so, you might want to use something like this

position the sensor in the right spot, and thats that :)

CementTruck (author)2014-05-22

I have a 2.5hp treadmill motor that I will be using to power my lathe/mill combo (the motor burned out last weekend in the middle of a project). Anyway, I would like to combine the lathe's capability of fwd/rev and the treadmill's speed controller. Here's what the wires look like coming from the switch to the motor through a junction box. I'm pretty sure that this is where the splicing is going to need to happen.

I don't want to run reverse polarity through the speed controller and fry something.

I want to do what this guy did (almost the same exact machine as mine but I have the older model with a mechanical chickenhead knob switch), but for the life of me can't figure out how he wired it up. If you could help me out with a simple hand drawn schematic or a link to someones page who has already managed it that would be great.

matas1 (author)CementTruck2014-07-18

Well, is your treadmill motor a DC motor? if so, you'll need to wire a switch between controller and a motor. there is a good instructable here:

CementTruck (author)matas12015-03-18

I figured out the wiring. I was over thinking it.

Now I have to figure out how to convert the original treadmill board's reading of MPH to RPM.

gfreed (author)2012-03-10

Any idea where to get a pulley to fit on a 17mm shaft? I guess I could drill out the center of 5/8 inch bore but I would think it would be difficult to keep it perfectly centered.

HughL (author)gfreed2015-03-12

old,I know, but just in case... 17mm shaft is very common for USA car alternator pulleys, only it is often referred to as .67 inch. I just put one on my 17mm motor shaft and it was a great fit. I had to drill and tap for a set screw and fields flat on the shaft for the set screw to engage. runs great! marked as 2hp, so something less. ran a jointer and a planer with no problems.

mrbreezeet1 (author)gfreed2014-12-20

needs to be bored on a lathe, after being carefully centered in a 4 jaw chuck.

loveoption9 (author)gfreed2012-06-21

I suggest you get a .040 thick shim and us a 3/4" bore pully, find some aluminum sheet that thick and form a little ring so that it fit snugly between the parts. some similar diameter tubing might work, 035"wall is common and might be close enough. Good luck. If you can make your project work with a 16mm it is almost identical to 5/8"

mrbreezeet1 (author)2014-11-26

Can I wire some type of spdt switch in this set up, so I can reverse the drive motor.

I want to use it to power my metal lathe lead screw, but I need it to go in both derections.

Efis7993 (author)2014-11-25

anyone know if the mc-68 controller can take dc input voltage? i have 120vdc system and am looking to control speed of ironworker with it. . will it work?

aliragaie (author)2014-06-10


aliragaie (author)2014-06-10


kaighn80 (author)2013-12-08

Hi, wonder if you have the pcb schematics for a motor controller, I found a 180v dc treadmill motor but I can't seem to locate a controller for one, I've decided that I'd be better off just building one. Any help would be greatly appreciated. My email address is
Thanks in advance.

kernbigo (author)2011-03-09

I have a threadmill board 4f33 nordic track, reebock, sears bought on ebay trying to figuire where to wire the 5k potentometer? help Kernbigo

About This Instructable




Bio: I like to learn new things.CNC, foundry, Screenprinting, anything electronics related. I like to tear things apart to see how they tick. Unless I ... More »
More by rjeblogue:Dishwasher Converted Pizza Oven-SmokerMake Eggrolls or Wontons on your Foreman grill, sandwich maker or waffle ironUse a Treadmill DC Drive Motor and PWM Speed Controller for powering tools
Add instructable to: