This video was perfect timing. I have 2 motors very similar to your video and was debating on which for my lathe and drill press. You confirmed my thoughts. As always thank you, Day.
I ran a fitness store for years -and we sold treadmills with that exact Pac-Sci motor in it...lots of them. in 8 years i think we replaced maybe 2 or 3 of those motors. the dinky little motors like the one on the right - saw many many of those burned out, or worn bearings sounding like a jet engine, or pulleys so small the heavy clients would cause them to slip and burn through belts. esp at low speeds the big motor can make a lot more torque, the small ones just bog down and slow down.
It’s funny that you came out with this video a day after you had messaged me back about another issue asking if I had done the torque calculation for my motors. Drill press is actually exactly what I was going to use the smaller motor for and I might just use the mc60 and control box I already have set up on the wood lathe for the drill press instead. That way I can use an SCR setup to get the most out of the larger motor on my lathe.
This helps. I have a couple smaller motors. Maybe I’ll make a variable speed shop fan and exhaust fan with them. The air flow should help cool them even if they are on for hours. I’m looking for a big motor for a variable speed conveyor belt as it will need lots of torque and be turning slow.
lots of torque and turning slow means you will need to gear it. Most treadmill motors have between 1 and 5 foot pounds of torque and come on around 400 RPM. Gear it at 8:1 and you will have 50 RPM and 8-40 foot pounds of torque.
I get that question a lot. The problem is manufacturers make lots of different models and then change the name of the model after only a couple years. I have found no constant brand or model. I do know this a cheap Walmart treadmill will have the smaller motor, the more expensive home units are much better with bigger motors and then the commercial units are the best.
I am a couple years late but I have a wood band saw that I would like to convert to a DC motor. I kind of see the band saw as being like the drill press where it really isn’t run for long periods BUT when cutting steel or other metals the load is significant. I don’t own a motor for the project so I’m a blank slate for options although I have started the hunt for a free treadmill donor.
The bigger issue with the band saw is torque. Bigger will be better, I know it was on my conversion Treadmill Bandsaw Conversion ruclips.net/p/PLg4j6XzBdSY8AkoE5YBqAHtnb5XDRIl8q
Thanks for the video, I have collected and disassembled lots of treadmills and have never run across a motor this large. Would you have a recommendation as to a specific brand I should look for?
that is the million dollar question. Problem is manufactures make several different models and the rebrand every couple years. I have scrapped about 20 and all of them have been different. short answer, I haven't got a list. I can say this however, there are three basic categories: home cheap, home high end, and professional gym. The big motor came from a professional level treadmill.
As always, awesome educational video. My question, have you happened to notice which treadmill brands generally use the bigger motor? Id like to know what to keep an eye out for so i can upgrade my equipment but i really need 2 of the bigger motors for the lathe and for the mill. The smaller motor was a fantastic upgrade to the small taig mill, and im super excited to finally get the stepper drivers for it so i can make it CNC. Thank you for all of the videos you make and i continue to tell all my friends and associates to check out your channel
That is the million dollar question. Problem is manufactures make several different models and they rebrand those models every couple years. I have scrapped about 20 and all of them have been different. Short answer, I haven't got a list. I can say this however, there are three basic categories: home cheap, home high end, and professional gym. The big motor in this video came from a professional level treadmill. Brands like Nordic track and Prcore tend to be better as well but that is just a general guideline not a hard fast rule.
I do enjoy the tread motor information, that's why I subscribed quite a while ago. You had a video on chokes in which you showed how to make an A/C choke. I bought one of the cores linked on that video and asked the question about what wire size to use when making an A/C choke. No answer! So I ask again, what size wire should be used? I'm guessimg between 14 gage and 16 gage but I'm unsure. Thanks for any reply.
I am sorry your previous question did't get answered. I try to answer all emails and youtube comments. Not sure how yours got missed. Was it an email or a youtube comment? 16 awg is a minimum 14 or 12 would be better. Please don't hesitate to reach out if I can be of any further assistance.
Real world or rule of thumb, you’re correct. Bigger is better because of thermal mass and some other characteristics, but I’m willing to bet an engineer could make a pretty good argument why you’re technically incorrect, starting with you’re not comparing apples to apples. An accurate efficiency curve for both motors is probably needed for that. That same engineer could probably design a geared motor and controller with very similar performance to a much larger motor, albeit with a lower duty cycle.
From a technical standpoint what you have said is true and yes "in theory..." But the common equalizer is $$ from a practical standpoint manufactures spend the bare minimum to make a product that meets their reliability standards and price point. In other words the "efficiency" is built into the equation as we are talking about repurposed motors. And for the sake of my channels content the apples to apples comparison is taking HP out of the equation AD or DC and going by torque because AC motors have a fluid torque curve where as in general DC motors have consistent torque regardless of RPM (except at the very bottom). HP means very little because manufactures can manipulate HP numbers at the expense of quality. Love the comment, thanks for taking the time to chime in.
Good day @ dazecars! Hope our doing well. In your video of motor torque and that size matters depending on the application, I was wondering where you sourced the bigger of the dc motors? I have a wood lathe I am going to be powering and I believe after viewing this video I am going to need the bigger size. Thank you for all your efforts!
Fishing... When you go fishing you never know what size fish you are going to pull out of the water but the longer you fish the better chance you have of catching a big one. I have scrapped about 20 treadmills and out of this 20 have gotten about 6 bigger motors. I was actively watching Facebook market place and craigslist and any time a free treadmill came up I snagged it.
Daze. Something I don’t understand. How can torque be a constant in a DC motor like this, if it’s dependent on RPM? T = HP x 5252/RPM. The motor specifies the HP and gives a maximum RPM. We can calculate torque from this. But what happens to the torque when the RPM drops? I’m still a bit confused about all of this. Also, on my Southbend heavy 10L lathe, I have a 3/4 HP AC motor. Speed adjustment is done with changing pulley wheel diameters. People on forums say that you don’t want to exceed 1 HP for this lathe. But what does it matter if the motor has more HP? Thanks, Paul
I can not speak to the HP limitations of your lathe as it does not seam to be a good spec to pick a motor by. Max RPM of the lathe and the torque the machine can handle are what is important. I can answer the other question. You are assuming HP is constant but it is not. HP is a function of torque. The HP stat on a motor is at the RPM stated on the motor. DC motors have constant torque so if you have 2 HP at 4000 RPM you will have 1 HP at 2000 RPM. The opposite is also true if you run that same motor at 8000 RPM you will have 4 HP. HP con not actually be measured. All we can measure is torque and RPM and we use those two numbers to calculate HP. This is how every dyno works everywhere. In most cases AC motors are designed to run at one speed so a constant RPM. If the motor is designed properly torque is maxed out at that speed which would also be max HP. Also AC and DC motors play by different rules so you can not take the specs of one and assume it will apply to the other. This is exactly why I created this video so people can create a common denomination and accurately compare an AC motor to a DC motor.
I don't have an answer there. The first thing you will need to do is look at voltage and get a motor that works at the voltage of your batteries. Either way you are likely not going to have anything that will perform as well as your gas engine
Hello, im not sure if this has been covered before, so im sorry if it has. I know these motors (generally, unless its really obvious it cant) can run in reverse. My question is can they be wired to run in the reverse direction (according to the motor tag) as the primary direction without doing harm? I have a treadmill motor hooked up running my wood lathe, but due to the rotation specified on the tag and the pulley location, length of the motor ect. I fear im getting wood dust sucked into the motor via the external fan. I cant imagine thats good for it. I have tried to make an "air filter" the best I can but I would rather move the motor around so I would have to worry less about it ( and it wouldnt be sticking into my work area) So I thought i'd ask before i go through the work and fabricate a new mount just to have the motor burn out shortly after. sorry for the novel, thanks in advance.
Assuming it is a DC motor witch most but not all treadmill motors are it should be reversible however first spin it by hand both directions. If it feels roughly the same both ways than it should be good to go. Wiring it is as simple as reversing the polarity. The other thing to consider is the motor flywheel and fan. A thread on flywheel may come off when run in revers and the fan should be reversed if running it in reverse so that air is moving through it the direction the manufacturer designed it too. Let me know if you have any other question.
Sorry I didn't start out with this, but Thank you for all of the time and effort you put into these videos and responses to comments. they are incredibly helpful and informative. I feel bad asking more of you. My motor is DC and I currently have it wired to run in reverse with a switch as outlined in one of your previous videos. I have the flywheel drilled and tapped with a set screw so that isn't an issue, mounting the fan on backwards would be easy as well. My question was more ( and I think you answered it, I just wanted to make doubly sure I didnt mis-read) would it cause harm over time to run it ONLY in reverse (assuming the fan was reversed to cool properly). I dont see why it would, but I like to check with much smarter people than myself@@dazecars
As long as it feels the same both directions when you spin it by hand there should not be any issue running in reverse all the time. Glad my videos have been helpful!!
I haven't seen anyone put a dc motor on a metal chop saw. I have a Hercules metal chop saw that i want to convert to a cold cut saw. The smaller dc motor looks like the easier candidate due to size. Just curious on your thoughts on this swap.
The smaller motor will work if and only if you do some serious gear reduction. Something in the neighborhood of 10:1 If you could make that happen it would be a good candidate because of the compact size and the intermittent use. A better bet would be to get a properly sized AC motor as there is really no need to very the speed on a metal cutting chop saw.
I agree with your points. But consider this. The cost of your super torque motor and controller? What rpm is needed to satisfy the requirements. I have a conversion of a Bridgeport type mill. The original motor was rated at 2 hp. I used a treadmill motor that was 3 hp and continuous of 2hp. Not only was I able to control the rpm by mechanical means- variable speed, of the mill, but I could also control the treadmill motor rpm. So, I satisfied the requirements, as far as rpm of the mill. The cost of the conversion was 200.00, and the cost of a Bridgeport motor was 2700.00. So, that is my argement. Did I make my point? Robert Brown.
Here is the link to the mill. By the way, you have not provided any bad news to me. Mill works great. Robert Brown. ruclips.net/video/jcKwKfgV96I/видео.html
The point of the video is you need to compare torque numbers not HP numbers because treadmill allows you to reduce RPM and HP is a function of RPM. Great that you got lucky and your motor worked but not all 2 HP motors will have enough torque to work in that same situation. Also $200 for a treadmill conversion is high IMHO. I'm into mine for around $50 and my motors are high quality ones.
It may “work” but you have put a 4 cyl in a sports car. Will it drive yes but it will be underpowered. Also the gearing required to get usable torque will shorten the life of what is already a cheap motor. I have a quality treadmill motor running both my lathe and my DIY mill, and didn’t spend more than $50 each. I would recommend getting the correct motor for your application.
Another great video, I like how you always explain it in layman terms. Out of curiosity, will all the different control boards control the larger size motor? I’ve salvaged a couple of the treadmill motors and control boards as well but haven’t put them to use yet. (This is how I stumbled upon your videos lol) I have the smaller one with an MC 60 control board and a larger one with the MC 2100. Just curious if the MC 60 will handle the larger motors? I bought the pulse generator that you recommended on your video and the MC 2100 works fine but of course is a lot more parts than the MC 60 which I know you tend to lean towards just curious if it’ll handle the “ larger” motors as well.
The MC60 and the MC21000 are budget controllers usually from mid to low end machines. High end treadmills have really nice power supplies but the only way I have found to use them is to retain the treadmill controls/functions. Any motor that came with a a MC60 or MC2100 should work with either power supply. A better option IMHO is a DIY SCR unit as it will provide more amps than the MC60 or MC2100 and amps are what create torque.
Thanks for the info, just to make sure im understanding. If geared to the same rpm and they have the same horsepower the output would be the same, but the bigger one would be able to run for much longer periods?
Yes. If they start with the same HP and are geared for the same RPM then yes they would function the same as the torque output would be identical after gearing. The smaller one would run hotter and use more electricity for the same work as it is less efficient.
Hey DazeCars can I ask you a question that's not exactly related to this video? I've got some money for my birthday so i'm planning on making a belt sander for knife making. but all the AC motors are too expensive , so i decided to go on the treadmill motor route after watching your videos. I can get a SCR and a bridge rectifier on aliexpress but not the dc choke , that i have to make with the microwave transformer as you showed. But my worry is that this is too DIY ee than anything i made in the past and i'm worried that it isn't going to last long , so will it if I do everything as you showed . can I atleast get a 1year of use out of a motor. My parents think that I should just saveup some more and get a AC motor but that would take way longer. Do you think I can trust this process . Thank you.
there are no moving parts so if you do it correctly from the beginning you will not have any issues. If you are worried about it keep looking for a choke. With a little patients they can still be found.
@@dazecars treadmill chokes are available here but costs about $30. so I have to go the microwave route. Then I will watch everyone of your videos about this and do as you showed. I hope you can help me along the way with any advise . thank you very much for the quick replay.
When trying to determine of the treadmill motor is comparable to the A/C motor you want to replace, would you calculate the A/C motor torque using the same formula as you do for the treadmill motor (HP x 5252)/ RPM?
If you spin that bigger motor to the same rpm as the small one, it'll make x amount more hp than the small one. If the small one makes a peak 2hp at 6k rpm, and the big one makes a peak 1.5hp at 3k rpm, the bigger motor will actually make 3hp at the same 6k rpm. Just another way of explaining it...
Best we can do as a community, share treadmill models & motors. For example: Pro-FormXP680 has a small 3.25” diameter motor. 2.8 hp@ 130V. 1.75hp -cont. duty @100V. Came with an MC-2100. I wish I knew the first one I scrapped. I got the big motor and is on my end mill. I’m still in the design phase with belts, pulleys etc. Does anyone else have designs they’d like to share. IG, FB page to compare designs?
That is a good idea. It would be a huge list however because each manufacturer has lots of models and they change every couple years. I have scrapped about 20 and none were the same make/model. Have you seen my home made mill build? You give me a good idea about sharing information, let me think on it... more to come.
@@dazecars indeed I have. Watched about 20 of the videos relating to wiring, SCR, power supply, design, etc. I started down this road when I couldn’t find an AC replacement motor to fit inside my mill/lathe combo. Seems the Obama administration legislated for higher efficiency electrics so motors got bigger in size to accommodate the law. Which for me, I couldn’t fit a new ac motor inside the frame. Planning a build can seem great until you realize your design doesn’t work. Just mounting the motor was difficult for me. My mill is round on the back so building brackets was a fete in itself. The throw for belt mounts, the height for belt alignment, would it clear the lower lathe guard? Will the wiring clear everything, purchasing belt sizes, pulley sizes and how to mount. It’s been a long road. I enjoy the challenge. Your channel has helped tremendously.
If you can reconnect the thermal wires I would. There is no reason not to run them if your motor comes with them. I have a couple "medium" quality motors that have have them they are "larger" but not as big as the one I show in my video (my biggest)
Great vid, thank you! Really would like your views on thd DC power supply impact on torque? Personally I'm getting some estimated 30% more low rpm torque using triac regulated AC with a good rectifier behind it, compared to my cheap PWM DC regulated power supply. Up to 30V I have even switched both power supplies in parallel and think thats best of both worlds. Do I make sense?
So from a theoretical standpoint a DC motor has the same torque across the entire RPM range. In reality there is a small amount of resistance in the wire used to make the coil so at lower volts that resistance effects amps. In other words at the very bottom of the RPM range you will see a loss in torque with most power supplies. At lower volts you lose torque because amps are what determines torque. I only find this to be an issue at the bottom 5-10% of the RPM range. The motor will draw a base amount of amps for normal spinning and then more as loads go up. I prefer an SCR type power supply with rectifier over a cheap PWM type power supply. Yes the power is less clean BUT I get enough amps for best possible torque at the majority of RPM ranges.
@@dazecars you inspire me to do some real life torque measerments now. I did put an oscilloscope on the motor and saw basically that pwm delivers somewhat interrupted power (pulses) and the motor hums. On rectified AC there's just straight lines and silence...
@@dazecars i have a very old pc based one, but with prices btwn 25 and 60 € on Ali i am considering buying a new one. Meanwhile I am pondering about a good and objective torque test. Think it has to be running torque rather than stall torque, otherwise I could use my tirque wrench
I put that small motor on my mini mill. I was milling a part for about an hour or so and decided to see how warm the motor was it was way too hot . And I didn’t put the thermocoupler back on it when I put it on the mill . That was stupid ! Do to size I would rather have the ac motor back on it.
Just a side note you should vary speed with PWM, not lowering voltage. You'll have a lot more torque at slower motor speeds than by changing the voltage
@@dazecars yes, current determines torque, but you cant push high current through a motor without increasing voltage. There's q reason variable speed drills use PWM (you can hear them squeal at partial trigger, thats PWM drive) its to maximize torque at lower revs. Simply lowering input voltage provides much less torque at comparable speeds.
That only applies at the lowest voltages, once the resistance of the coil is overcome voltage no longer becomes an issue. That usually happens (depending on the coil) around 5V. You are talking about a 12v or 18v system and applying your observations universally. I am working with 90-135v motors. At EVERYTHING but the very slowest speeds there is more than enough voltage to overcome the resistance of the coil and apply max torque. Either way the effect of PWM lowers the voltage. If you don't believe me put a meter to it. The concept is universal, if you lower the voltage on a DC motor you lower the speed. How you lower that voltage can effect function but only at the lowest voltages. I stand by what I said. @@VJ-ft2xj
@@dazecars do you know what controller type that can keep a motor at a lower rpm under load? I know there is a way. I have one in a shopsmith as the motor went out on me, & at the lower speeds it is gutless.
This video might help you. I strongly recommend gearing when possible because in most cases more torque and less RPM is a good thing. ruclips.net/video/AdGypyO_UuM/видео.html
It is all about "fishing" I have Craigslist and Facebook market place setup to to email me when treadmills come up. I would say out of the 18-20 I have scrapped out 5 had a good motor.
a lot of people are using those. I have not used one personally but it is my understanding they work well for medium to smaller project but are not as potent as a bigger treadmill motor. Which one are you using and what are you using it on?
Best to no go the treadmill motor route full stop They are just not anywhere as capable as a 3 Phase motor running off a VFD I tried everything as far as treadmill motors are concerned and never came close to what is now the cheaper and far more controllable option It like everything it has had its day and no complex wiring , Inductors , Chokes , Chinese scr , Breakers , rectifiers, with a VFD you can program it to do anything you want , Ramp up , Ramp down , Jog , And a hundred more
Your comment is only valid if you have three phase available, the expense of connecting three phase far outweighs the advantage for a hobby shop. If your three phase motor can not be configured to suit the mains voltage a VFD is not an option, VFD,s that will increase voltage above supply voltage cost much more than the DIY DC motor option.
I totally respect that that is your experience and observation but its not one size fits all. I have hobby size machines and the treadmill motors are a huge upgrade. My mill, my lathe and my bandsaw are all far more usable due to this upgrade. I have helped hundreds if not thousands of people convert to treadmill motors with resounding success. It all depends on the size of the motor, the size of the machine, and the application. A large machine used all day long may not work well even with the biggest treadmill motors. If a treadmill type motor wasn't a better option a lot of hobby machines wouldn't now come with DC motors similar to what you find in a treadmill. An AC motor and pulley system would be cheaper for the manufacturer. I will not argue that a good 3 phase motor and a VFD is superior to a treadmill setup but for most hobby machines its over kill. If you have a sports car and a truck lined up on a gravel rod neither one will be able to go very fast. I understand that it was not an upgrade for you but that doesn't mean it applies to everyone. Thanks for the your comment
Many Thanks for that and yes of course it is horses for courses , And at the monemt I should be the last to say that treadmill motors are not the way to go , I recently purchased as Spirit fitness Treadmill for 99p yes 99p If I had not taken it away it was going for scrap , Within it had a 3 HP 220v VFD dedicated 3 phase motor controlled by a C200 Delta VFD ,That surely is lucky as hell it had hardly been used due to the main switch failing and the company going bankrupt HEY That is now powering my Viceroy Lathe with a Rocketronic ELS , an engineers dream come true I have wathched all of your vids over a long period of time and you are a very clever man and for sure worked out the best way to do this using dc motors , I have one on my small mill Just been spoilt recently Keep up the good work
@@mechanical1955 When those commercial grade AC treadmills become old and replaced then maybe the averge hobbist might be able to find one. They sure are better than a DC motor but rare for free or little money unlike large DC treadmills that I see often from people who just want them gone. I watched a local clearance auction of a gym that closed recently thinking I might score a commercial treadmill for cheap. No. They all went for over $1500.
They come from used treadmills so they are by no means new. Good news is there are not a lot of technological advances to a basic DC motor. Would be different if it was a stepper or servo that has other electronic components.
This video was perfect timing. I have 2 motors very similar to your video and was debating on which for my lathe and drill press. You confirmed my thoughts. As always thank you, Day.
Glad I could help
I ran a fitness store for years -and we sold treadmills with that exact Pac-Sci motor in it...lots of them. in 8 years i think we replaced maybe 2 or 3 of those motors. the dinky little motors like the one on the right - saw many many of those burned out, or worn bearings sounding like a jet engine, or pulleys so small the heavy clients would cause them to slip and burn through belts. esp at low speeds the big motor can make a lot more torque, the small ones just bog down and slow down.
That’s excellent real world information, thanks for the comment.
It’s funny that you came out with this video a day after you had messaged me back about another issue asking if I had done the torque calculation for my motors. Drill press is actually exactly what I was going to use the smaller motor for and I might just use the mc60 and control box I already have set up on the wood lathe for the drill press instead. That way I can use an SCR setup to get the most out of the larger motor on my lathe.
yes how I will do it. The MC 60 is okay but not near as good as a properly assembled SCR setup.
@@dazecars I don’t have a second controller for the other motor so I would have had to buy one anyway. Now a second choke will be needed as well.
the MC60 will probably be okay for a drill press BUT you really should run a choke with that as well. @@FTADaddio
This helps. I have a couple smaller motors. Maybe I’ll make a variable speed shop fan and exhaust fan with them. The air flow should help cool them even if they are on for hours. I’m looking for a big motor for a variable speed conveyor belt as it will need lots of torque and be turning slow.
lots of torque and turning slow means you will need to gear it. Most treadmill motors have between 1 and 5 foot pounds of torque and come on around 400 RPM. Gear it at 8:1 and you will have 50 RPM and 8-40 foot pounds of torque.
It would be nice to know which treadmills have the larger motors
I get that question a lot. The problem is manufacturers make lots of different models and then change the name of the model after only a couple years. I have found no constant brand or model. I do know this a cheap Walmart treadmill will have the smaller motor, the more expensive home units are much better with bigger motors and then the commercial units are the best.
I am a couple years late but I have a wood band saw that I would like to convert to a DC motor. I kind of see the band saw as being like the drill press where it really isn’t run for long periods BUT when cutting steel or other metals the load is significant.
I don’t own a motor for the project so I’m a blank slate for options although I have started the hunt for a free treadmill donor.
The bigger issue with the band saw is torque. Bigger will be better, I know it was on my conversion Treadmill Bandsaw Conversion
ruclips.net/p/PLg4j6XzBdSY8AkoE5YBqAHtnb5XDRIl8q
Thanks for the video, I have collected and disassembled lots of treadmills and have never run across a motor this large. Would you have a recommendation as to a specific brand I should look for?
that is the million dollar question. Problem is manufactures make several different models and the rebrand every couple years. I have scrapped about 20 and all of them have been different. short answer, I haven't got a list. I can say this however, there are three basic categories: home cheap, home high end, and professional gym. The big motor came from a professional level treadmill.
I tore apart a Nortic Trac Pro treadmill and it has a motor that is just about that size (2.25hp 130vDC) but bug and heavy like the photo.
That is why the best way to know what you have is to calculate the torque. Size is just a rough estimate
Thanks for your reply. Guess I've got some fishing 🎣 to do. 😆
thats half the fun 😂
Great video. Can't wait to see you gear that smaller motor and put it on your drill press. I was wondering what I could do with my smaller motor.
me too 😁 it has been a project on the list for a few years. I will get to it eventually. So many projects so little time.
As always, awesome educational video. My question, have you happened to notice which treadmill brands generally use the bigger motor? Id like to know what to keep an eye out for so i can upgrade my equipment but i really need 2 of the bigger motors for the lathe and for the mill. The smaller motor was a fantastic upgrade to the small taig mill, and im super excited to finally get the stepper drivers for it so i can make it CNC. Thank you for all of the videos you make and i continue to tell all my friends and associates to check out your channel
That is the million dollar question. Problem is manufactures make several different models and they rebrand those models every couple years. I have scrapped about 20 and all of them have been different. Short answer, I haven't got a list. I can say this however, there are three basic categories: home cheap, home high end, and professional gym. The big motor in this video came from a professional level treadmill. Brands like Nordic track and Prcore tend to be better as well but that is just a general guideline not a hard fast rule.
thank you so much for these precious information..
My pleasure
Great video. Thanks for posting.
My pleasure!
I do enjoy the tread motor information, that's why I subscribed quite a while ago. You had a video on chokes in which you showed how to make an A/C choke. I bought one of the cores linked on that video and asked the question about what wire size to use when making an A/C choke. No answer! So I ask again, what size wire should be used? I'm guessimg between 14 gage and 16 gage but I'm unsure. Thanks for any reply.
If you know the amperage you want, use that to determine your wire gauge.
If it gets too hot, use a bigger wire.
I am sorry your previous question did't get answered. I try to answer all emails and youtube comments. Not sure how yours got missed. Was it an email or a youtube comment? 16 awg is a minimum 14 or 12 would be better. Please don't hesitate to reach out if I can be of any further assistance.
I just did a search under "wire size" and saw this comment but no others.
Thank you.
Real world or rule of thumb, you’re correct. Bigger is better because of thermal mass and some other characteristics, but I’m willing to bet an engineer could make a pretty good argument why you’re technically incorrect, starting with you’re not comparing apples to apples. An accurate efficiency curve for both motors is probably needed for that. That same engineer could probably design a geared motor and controller with very similar performance to a much larger motor, albeit with a lower duty cycle.
From a technical standpoint what you have said is true and yes "in theory..." But the common equalizer is $$ from a practical standpoint manufactures spend the bare minimum to make a product that meets their reliability standards and price point. In other words the "efficiency" is built into the equation as we are talking about repurposed motors. And for the sake of my channels content the apples to apples comparison is taking HP out of the equation AD or DC and going by torque because AC motors have a fluid torque curve where as in general DC motors have consistent torque regardless of RPM (except at the very bottom). HP means very little because manufactures can manipulate HP numbers at the expense of quality. Love the comment, thanks for taking the time to chime in.
Good day @ dazecars! Hope our doing well. In your video of motor torque and that size matters depending on the application, I was wondering where you sourced the bigger of the dc motors? I have a wood lathe I am going to be powering and I believe after viewing this video I am going to need the bigger size. Thank you for all your efforts!
Fishing... When you go fishing you never know what size fish you are going to pull out of the water but the longer you fish the better chance you have of catching a big one. I have scrapped about 20 treadmills and out of this 20 have gotten about 6 bigger motors. I was actively watching Facebook market place and craigslist and any time a free treadmill came up I snagged it.
Daze. Something I don’t understand. How can torque be a constant in a DC motor like this, if it’s dependent on RPM?
T = HP x 5252/RPM.
The motor specifies the HP and gives a maximum RPM. We can calculate torque from this. But what happens to the torque when the RPM drops?
I’m still a bit confused about all of this.
Also, on my Southbend heavy 10L lathe, I have a 3/4 HP AC motor. Speed adjustment is done with changing pulley wheel diameters. People on forums say that you don’t want to exceed 1 HP for this lathe. But what does it matter if the motor has more HP?
Thanks,
Paul
I can not speak to the HP limitations of your lathe as it does not seam to be a good spec to pick a motor by. Max RPM of the lathe and the torque the machine can handle are what is important.
I can answer the other question. You are assuming HP is constant but it is not. HP is a function of torque. The HP stat on a motor is at the RPM stated on the motor. DC motors have constant torque so if you have 2 HP at 4000 RPM you will have 1 HP at 2000 RPM. The opposite is also true if you run that same motor at 8000 RPM you will have 4 HP. HP con not actually be measured. All we can measure is torque and RPM and we use those two numbers to calculate HP. This is how every dyno works everywhere. In most cases AC motors are designed to run at one speed so a constant RPM. If the motor is designed properly torque is maxed out at that speed which would also be max HP. Also AC and DC motors play by different rules so you can not take the specs of one and assume it will apply to the other. This is exactly why I created this video so people can create a common denomination and accurately compare an AC motor to a DC motor.
What DC electric motor would work best in a small outboard motor? For example if I removed the 9.9 hp engine and replaced it with a motor. Thanks.
I don't have an answer there. The first thing you will need to do is look at voltage and get a motor that works at the voltage of your batteries. Either way you are likely not going to have anything that will perform as well as your gas engine
Hello, im not sure if this has been covered before, so im sorry if it has. I know these motors (generally, unless its really obvious it cant) can run in reverse. My question is can they be wired to run in the reverse direction (according to the motor tag) as the primary direction without doing harm?
I have a treadmill motor hooked up running my wood lathe, but due to the rotation specified on the tag and the pulley location, length of the motor ect. I fear im getting wood dust sucked into the motor via the external fan. I cant imagine thats good for it. I have tried to make an "air filter" the best I can but I would rather move the motor around so I would have to worry less about it ( and it wouldnt be sticking into my work area)
So I thought i'd ask before i go through the work and fabricate a new mount just to have the motor burn out shortly after.
sorry for the novel, thanks in advance.
Assuming it is a DC motor witch most but not all treadmill motors are it should be reversible however first spin it by hand both directions. If it feels roughly the same both ways than it should be good to go. Wiring it is as simple as reversing the polarity. The other thing to consider is the motor flywheel and fan. A thread on flywheel may come off when run in revers and the fan should be reversed if running it in reverse so that air is moving through it the direction the manufacturer designed it too. Let me know if you have any other question.
Sorry I didn't start out with this, but Thank you for all of the time and effort you put into these videos and responses to comments. they are incredibly helpful and informative. I feel bad asking more of you.
My motor is DC and I currently have it wired to run in reverse with a switch as outlined in one of your previous videos. I have the flywheel drilled and tapped with a set screw so that isn't an issue, mounting the fan on backwards would be easy as well. My question was more ( and I think you answered it, I just wanted to make doubly sure I didnt mis-read) would it cause harm over time to run it ONLY in reverse (assuming the fan was reversed to cool properly). I dont see why it would, but I like to check with much smarter people than myself@@dazecars
As long as it feels the same both directions when you spin it by hand there should not be any issue running in reverse all the time. Glad my videos have been helpful!!
Thanks for the video Daze
Any time!
I haven't seen anyone put a dc motor on a metal chop saw. I have a Hercules metal chop saw that i want to convert to a cold cut saw. The smaller dc motor looks like the easier candidate due to size. Just curious on your thoughts on this swap.
The smaller motor will work if and only if you do some serious gear reduction. Something in the neighborhood of 10:1 If you could make that happen it would be a good candidate because of the compact size and the intermittent use. A better bet would be to get a properly sized AC motor as there is really no need to very the speed on a metal cutting chop saw.
I agree with your points. But consider this. The cost of your super torque motor and controller? What rpm is needed to satisfy the requirements. I have a conversion of a Bridgeport type mill. The original motor was rated at 2 hp. I used a treadmill motor that was 3 hp and continuous of 2hp. Not only was I able to control the rpm by mechanical means- variable speed, of the mill, but I could also control the treadmill motor rpm. So, I satisfied the requirements, as far as rpm of the mill. The cost of the conversion was 200.00, and the cost of a Bridgeport motor was 2700.00. So, that is my argement. Did I make my point? Robert Brown.
Here is the link to the mill. By the way, you have not provided any bad news to me. Mill works great. Robert Brown.
ruclips.net/video/jcKwKfgV96I/видео.html
The point of the video is you need to compare torque numbers not HP numbers because treadmill allows you to reduce RPM and HP is a function of RPM. Great that you got lucky and your motor worked but not all 2 HP motors will have enough torque to work in that same situation. Also $200 for a treadmill conversion is high IMHO. I'm into mine for around $50 and my motors are high quality ones.
Thsat is WAY UNDER SIZED. I hope it works out for yopu but I would be looking for a better motor. Good luck with that
I saved 2500.00 on my conversion and it works well. You can talk torque all day, but, if it works, it works.
It may “work” but you have put a 4 cyl in a sports car. Will it drive yes but it will be underpowered. Also the gearing required to get usable torque will shorten the life of what is already a cheap motor. I have a quality treadmill motor running both my lathe and my DIY mill, and didn’t spend more than $50 each. I would recommend getting the correct motor for your application.
Fantastic summary 👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍
Glad you liked it!
Another great video, I like how you always explain it in layman terms. Out of curiosity, will all the different control boards control the larger size motor? I’ve salvaged a couple of the treadmill motors and control boards as well but haven’t put them to use yet. (This is how I stumbled upon your videos lol) I have the smaller one with an MC 60 control board and a larger one with the MC 2100. Just curious if the MC 60 will handle the larger motors? I bought the pulse generator that you recommended on your video and the MC 2100 works fine but of course is a lot more parts than the MC 60 which I know you tend to lean towards just curious if it’ll handle the “ larger” motors as well.
The MC60 and the MC21000 are budget controllers usually from mid to low end machines. High end treadmills have really nice power supplies but the only way I have found to use them is to retain the treadmill controls/functions. Any motor that came with a a MC60 or MC2100 should work with either power supply. A better option IMHO is a DIY SCR unit as it will provide more amps than the MC60 or MC2100 and amps are what create torque.
Thanks for the info, just to make sure im understanding. If geared to the same rpm and they have the same horsepower the output would be the same, but the bigger one would be able to run for much longer periods?
Yes. If they start with the same HP and are geared for the same RPM then yes they would function the same as the torque output would be identical after gearing. The smaller one would run hotter and use more electricity for the same work as it is less efficient.
At 2:52 you refer to a video about HP. Can you provide a link to that video?
Determining if your treadmill motor has enough torque for the project you want to add it to.
ruclips.net/video/A_zBGJkhBAc/видео.html
great review on the motors
Glad you liked it. Thanks for commenting!
Hey DazeCars can I ask you a question that's not exactly related to this video? I've got some money for my birthday so i'm planning on making a belt sander for knife making. but all the AC motors are too expensive , so i decided to go on the treadmill motor route after watching your videos. I can get a SCR and a bridge rectifier on aliexpress but not the dc choke , that i have to make with the microwave transformer as you showed. But my worry is that this is too DIY ee than anything i made in the past and i'm worried that it isn't going to last long , so will it if I do everything as you showed . can I atleast get a 1year of use out of a motor. My parents think that I should just saveup some more and get a AC motor but that would take way longer. Do you think I can trust this process . Thank you.
there are no moving parts so if you do it correctly from the beginning you will not have any issues. If you are worried about it keep looking for a choke. With a little patients they can still be found.
@@dazecars treadmill chokes are available here but costs about $30. so I have to go the microwave route. Then I will watch everyone of your videos about this and do as you showed. I hope you can help me along the way with any advise . thank you very much for the quick replay.
👍
When trying to determine of the treadmill motor is comparable to the A/C motor you want to replace, would you calculate the A/C motor torque using the same formula as you do for the treadmill motor (HP x 5252)/ RPM?
Yes, it’s the exact same formula for both.
Super good stuff tanks 🎉
My pleasure. Thanks for watching
As an old mechanic,,, 😎 There's no substitute for cubes 👍
You got that right! "no replacement for displacement"
If you spin that bigger motor to the same rpm as the small one, it'll make x amount more hp than the small one.
If the small one makes a peak 2hp at 6k rpm, and the big one makes a peak 1.5hp at 3k rpm, the bigger motor will actually make 3hp at the same 6k rpm. Just another way of explaining it...
good point, thanks for the comment!
Best we can do as a community, share treadmill models & motors. For example: Pro-FormXP680 has a small 3.25” diameter motor. 2.8 hp@ 130V. 1.75hp -cont. duty @100V. Came with an MC-2100. I wish I knew the first one I scrapped. I got the big motor and is on my end mill. I’m still in the design phase with belts, pulleys etc. Does anyone else have designs they’d like to share. IG, FB page to compare designs?
That is a good idea. It would be a huge list however because each manufacturer has lots of models and they change every couple years. I have scrapped about 20 and none were the same make/model. Have you seen my home made mill build? You give me a good idea about sharing information, let me think on it... more to come.
@@dazecars indeed I have. Watched about 20 of the videos relating to wiring, SCR, power supply, design, etc. I started down this road when I couldn’t find an AC replacement motor to fit inside my mill/lathe combo. Seems the Obama administration legislated for higher efficiency electrics so motors got bigger in size to accommodate the law. Which for me, I couldn’t fit a new ac motor inside the frame. Planning a build can seem great until you realize your design doesn’t work. Just mounting the motor was difficult for me. My mill is round on the back so building brackets was a fete in itself. The throw for belt mounts, the height for belt alignment, would it clear the lower lathe guard? Will the wiring clear everything, purchasing belt sizes, pulley sizes and how to mount. It’s been a long road. I enjoy the challenge. Your channel has helped tremendously.
"mill Lathe combo" are you a member of my combo Facebook page?@@dathonlawler81
I have 2 of the big motors with the Thermal cut off on them.
If you can reconnect the thermal wires I would. There is no reason not to run them if your motor comes with them. I have a couple "medium" quality motors that have have them they are "larger" but not as big as the one I show in my video (my biggest)
Great vid, thank you! Really would like your views on thd DC power supply impact on torque? Personally I'm getting some estimated 30% more low rpm torque using triac regulated AC with a good rectifier behind it, compared to my cheap PWM DC regulated power supply. Up to 30V I have even switched both power supplies in parallel and think thats best of both worlds. Do I make sense?
So from a theoretical standpoint a DC motor has the same torque across the entire RPM range. In reality there is a small amount of resistance in the wire used to make the coil so at lower volts that resistance effects amps. In other words at the very bottom of the RPM range you will see a loss in torque with most power supplies. At lower volts you lose torque because amps are what determines torque. I only find this to be an issue at the bottom 5-10% of the RPM range. The motor will draw a base amount of amps for normal spinning and then more as loads go up. I prefer an SCR type power supply with rectifier over a cheap PWM type power supply. Yes the power is less clean BUT I get enough amps for best possible torque at the majority of RPM ranges.
@@dazecars you inspire me to do some real life torque measerments now. I did put an oscilloscope on the motor and saw basically that pwm delivers somewhat interrupted power (pulses) and the motor hums. On rectified AC there's just straight lines and silence...
m.ruclips.net/video/ZU9LQTl86Uo/видео.html if you're interested
I really need to get an oscilloscope. some of the testing I do could really benefit from one.@@kees-tanis
@@dazecars i have a very old pc based one, but with prices btwn 25 and 60 € on Ali i am considering buying a new one. Meanwhile I am pondering about a good and objective torque test. Think it has to be running torque rather than stall torque, otherwise I could use my tirque wrench
I put that small motor on my mini mill. I was milling a part for about an hour or so and decided to see how warm the motor was it was way too hot . And I didn’t put the thermocoupler back on it when I put it on the mill . That was stupid ! Do to size I would rather have the ac motor back on it.
did you have it geared to maximize torque? Also did you retain the flywheel as a cooling fan?
Just a side note you should vary speed with PWM, not lowering voltage. You'll have a lot more torque at slower motor speeds than by changing the voltage
PWM in effect lowers the voltage. Besides, it's amps that determine torque not voltage.
@@dazecars yes, current determines torque, but you cant push high current through a motor without increasing voltage. There's q reason variable speed drills use PWM (you can hear them squeal at partial trigger, thats PWM drive) its to maximize torque at lower revs. Simply lowering input voltage provides much less torque at comparable speeds.
That only applies at the lowest voltages, once the resistance of the coil is overcome voltage no longer becomes an issue. That usually happens (depending on the coil) around 5V. You are talking about a 12v or 18v system and applying your observations universally. I am working with 90-135v motors. At EVERYTHING but the very slowest speeds there is more than enough voltage to overcome the resistance of the coil and apply max torque. Either way the effect of PWM lowers the voltage. If you don't believe me put a meter to it. The concept is universal, if you lower the voltage on a DC motor you lower the speed. How you lower that voltage can effect function but only at the lowest voltages. I stand by what I said. @@VJ-ft2xj
I have the little motor on a 2x72 grinder and it has ran 2 to 3 hours straight before.
When setup properly the smaller motors can run for hours the issues arise when people try to push the motor past its' normal operating range
@@dazecars do you know what controller type that can keep a motor at a lower rpm under load? I know there is a way. I have one in a shopsmith as the motor went out on me, & at the lower speeds it is gutless.
This video might help you. I strongly recommend gearing when possible because in most cases more torque and less RPM is a good thing. ruclips.net/video/AdGypyO_UuM/видео.html
@@dazecars Going to watch right now. Trying to do a poor mans power pro headstock. They go from 200rpm to 10,000 rpm
That is quite an RPM range and will make finding the right motor tough
All the treadmills I've parted out have roughly the same motors. Id love to stumble across a big one for my lathe
It is all about "fishing" I have Craigslist and Facebook market place setup to to email me when treadmills come up. I would say out of the 18-20 I have scrapped out 5 had a good motor.
@@dazecars what kinds of treadmills have you found the larger motors to be in?
I've only disassembled 2 treadmills so far and both had large motors. At some point I'll get a small one.
1 was a Proform and the other was a Spirit. Can't remember the specific models.
were they high end home or professional grade?@@Camoburb
Power is just the rate t which torque is applied.
Anyone who says Power is more important is missing something.
Agreed!!
I run a large sewing machine motor DC.
I was wondering about those motors
a lot of people are using those. I have not used one personally but it is my understanding they work well for medium to smaller project but are not as potent as a bigger treadmill motor. Which one are you using and what are you using it on?
If torque matters someone should try axial flux :D
yes but then it would not be free 😁
Best to no go the treadmill motor route full stop
They are just not anywhere as capable as a 3 Phase motor running off a VFD
I tried everything as far as treadmill motors are concerned and never came close to what is now the cheaper and far more controllable
option
It like everything it has had its day and no complex wiring , Inductors , Chokes , Chinese scr , Breakers , rectifiers, with a VFD you can program it to do anything you want , Ramp up , Ramp down , Jog , And a hundred more
Your comment is only valid if you have three phase available, the expense of connecting three phase far outweighs the advantage for a hobby shop. If your three phase motor can not be configured to suit the mains voltage a VFD is not an option, VFD,s that will increase voltage above supply voltage cost much more than the DIY DC motor option.
I totally respect that that is your experience and observation but its not one size fits all. I have hobby size machines and the treadmill motors are a huge upgrade. My mill, my lathe and my bandsaw are all far more usable due to this upgrade. I have helped hundreds if not thousands of people convert to treadmill motors with resounding success. It all depends on the size of the motor, the size of the machine, and the application. A large machine used all day long may not work well even with the biggest treadmill motors. If a treadmill type motor wasn't a better option a lot of hobby machines wouldn't now come with DC motors similar to what you find in a treadmill. An AC motor and pulley system would be cheaper for the manufacturer. I will not argue that a good 3 phase motor and a VFD is superior to a treadmill setup but for most hobby machines its over kill. If you have a sports car and a truck lined up on a gravel rod neither one will be able to go very fast. I understand that it was not an upgrade for you but that doesn't mean it applies to everyone. Thanks for the your comment
VFD setup runs off single phase@@garychaplin9861
Many Thanks for that and yes of course it is horses for courses , And at the monemt I should be the last to say that treadmill motors are not the way to go , I recently purchased as Spirit fitness Treadmill for 99p yes 99p If I had not taken it away it was going for scrap , Within it had a 3 HP 220v VFD dedicated 3 phase motor controlled by a C200 Delta VFD ,That surely is lucky as hell it had hardly been used due to the main switch failing and the company going bankrupt HEY
That is now powering my Viceroy Lathe with a Rocketronic ELS , an engineers dream come true
I have wathched all of your vids over a long period of time and you are a very clever man and for sure worked out the best way to do this using dc motors , I have one on my small mill
Just been spoilt recently
Keep up the good work
@@mechanical1955 When those commercial grade AC treadmills become old and replaced then maybe the averge hobbist might be able to find one. They sure are better than a DC motor but rare for free or little money unlike large DC treadmills that I see often from people who just want them gone.
I watched a local clearance auction of a gym that closed recently thinking I might score a commercial treadmill for cheap. No. They all went for over $1500.
These motors look dated. Modern DC motors may be better Tech, generally speaking of course 😮
They come from used treadmills so they are by no means new. Good news is there are not a lot of technological advances to a basic DC motor. Would be different if it was a stepper or servo that has other electronic components.