Metal Lathe Treadmill Motor Conversion & Treadmill Motor Controller
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- čas přidán 1. 06. 2024
- I realized with all the videos I have done I never provided more info on my actual lathe conversion. This walks through my entire setup and show all the parts and modifications necessary to put a treadmill motor on a metal lathe.
Affiliate links to items in this video:
SCR Voltage controller:
SCR voltage controller amzn.to/47vUify
100 amp Bridge rectifier amzn.to/40DjWg6
20 Amp circuit breaker amzn.to/3ufQDRh
OR
15 Amp circuit breaker amzn.to/3FgoQGP
Emergency stop switch amzn.to/43mgveT
3PDT direction switch amzn.to/3ZShNLG
OR
DPDT center of switch amzn.to/46hjbdM
Toroid Core for AC inductor/choke amzn.to/3QTk5Zs
10K potentiometer amzn.to/3QAtiES
20K potentiometer amzn.to/3Srib1a
100K potentiometer amzn.to/46anc3O
150K potentiometer amzn.to/3zxc96l
Inclosuers and inclosure parts:
8” X 6” X 4” hinged box amzn.to/3jPndaR
8” X 10” X 4” Power supply box amzn.to/3HEHeun
12” x 12” x 4” Large component box amzn.to/3Imerv6
7.9” x 4.7” x 2.95” Large plastic box amzn.to/3nQEylT
6.22” x 3.54” x 2.36” Medium plastic box (the one I put all the parts in) amzn.to/40JB9nn
Cable Gland amzn.to/3VZNrWb
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. - Auta a dopravní prostředky
Great job circling back to this. It really helps show the value and utility of a lot of your other content
Thnks!!
I need to get off the bench and just do it already instead of watching all of you guys' youtube videos. Thank you for the wealth of information.
I set up my last Smithy AT300 (similar machine as yours) the cheap way after the original motor burned up and used the treadmill controls to run the motor. I was even able to power tap. It was an upgrade to be sure.
as your project progresses don't hesitate to reach out if any questions arise.
All 3 of my vintage lathes run on treadmill motors. Such a great upgrade and making the controller is super easy.
Totally agree! its no VFD but is also 1/10 the cost and almost as good.
Hi
I've watched a few of your videos now. I have collected a few treadmill motors but not successful got one too work. You have now given me inspiration to try again.
Keep up the good work and wish me luck 🤞
Let me know if anything comes up that I can help with.
Thanks for sharing your experience
My pleasure
Good dose of info there Dawg.
Much appreciated
New subscriber from mid-Canada. I too have converted my mill lathe to treadmill power. I want to learn to add the fine speed potentiometer.🎉
Welcome aboard! What are you using as a power supply for your treadmill motor?
Great video!
Glad you enjoyed it
Yo you have been posting videos lately in direct correlation to the same problems I’ve been having with my lathe conversions!! You my friend are a badass! Thank you for what you have been doing 🤙🏼🙏🏼 learned that my motor is dog shit and have to find yet ANOTHER treadmill with a stronger motor🤦🏻♂️ any suggestions other than offer up..? Also, I’m personally doing a wood lathe conversion and been having a helluva time finding a way to mount the bitch on my frame all while still keeping the pivoting function for belt tensioning…got any ideas…? Once again you are the man, you explain things in a way that I can comprehend (which is rare nowadays I guess, the other videos on “treadmill motor conversion” are DOG SHIT!!!
I don't know about badass, but I do appreciate the compliment!! As for finding them I have Craiglest email me every time a treadmill comes up. Most of them are $$ but some are free. I also check Facebook marketplace ever couple days. I find about 4 free treadmills a year. Some are good and some are not so good but all have good usable parts for a verity of projects. I might be able to help with the mounting situation if you emailed me pix.
Great video. Do you have a wiring diagram for the 2 potentiometers? How are they wired to the SCR?
I have something better than a diagram, I did a vido on it 😁😁 czcams.com/video/04d0u1RJyXw/video.html
I think I'll redo the control setup on my treadmill motorized wood lathe. First I'll neaten up the wiring paths and provide better dustproof ventilation of the controller board and choke. And I'll make a comprehensive schematic with photos too.
Many/most woodturners just crank up the RPMs until the lathe shakes and then back it down, which may be practical but is not optimal. Depending on species and condition of the wood, then the angular velocity can be a factor in achieving a good surface finish on the workpiece.
Currently, I use a cheap HF DVM to set RPM by monitoring the control voltage of the MC40 board at the wiper of the potentiometer. I determined the relationship between voltage & RPM by setting the motor to various RPMs as measured with a model aircraft tachometer pointed at the spindle, and then noted the voltage. Then I graphed and printed out the relationship for reference. (Note: it's futile to use such a tachometer under fluorescent or LED light!) I'll replace that Rube Goldberg setup with a Hall-effect tach and LED display.
It may be interesting to note that I use a dinky J3 poly-vee dryer belt for power transmission because the lathe step pulley and motor match this standard. It's worked for 8-10 years now with no problems because the flywheel and chuck store enough energy for cutting. If I stall the lathe then I know that it's time to sharpen the chisels to relieve excess loading pressure. Note that I'm not hogging off thick shavings that require a hefty torque.
Sounds like a fun project
Hi, great video
Can you tell me how do you setup a AC ferrite choke?
I am trying to convert my lathe motor.
Thanks
czcams.com/video/WRT_Ri18eLY/video.html
lathe chucks have a max rpm ,,, sure you know that ,,,but your such a good source of information I wouldn't want you to have a major whoopsy
Thanks!! and that is a good point. When I set my machines up I did it with max desired RPMs in mind not wanting to go much over the original RPM amount for not only the chuck but also spindle bearing life. I also wanted to maximize torque at all speeds so I used the pulley ratio to put max Motor RPMS close to max machine RPMS in the original configuration prior to the treadmill motor swap.
Very cool. Thanks for sharing. So you say a lathe without a halfnut. Now you can thread with it. So does that mean that you converted it to cnc?
nope just added ELS czcams.com/video/47Xyfnvqpes/video.html
Nice proje.
thanks
Could I ask a quick question, when calculating torque comparisons of different motors, doesn't the gear ratio of the drive pulley effect the power of the machine? For instance I have a dc motor with 2.33 torque value that spins at 4500rpm compared to an existing ac motor with a torque value of 2.8 that spins at 1400rpm. If I gear both motors so they power for example a lathe chuck at max 2500rpm won't the dc motor produce more power as it would be geared down to rotate the lathe chuck at 2500rpm where as the ac motor would be geared up to rotate the lathe chuck at 2500rpm?....
You are 100% correct that gearing it down will help balance torque or in this case give you more. Keep in mind the entire reason for running a treadmill motor is reduced speed so you will be often times running it at a slower speed which reduces HP. Also as an example in the case of my lathe I set up the new motor with the same pulley system as the old motors slowest setting 3.5:1. Running a lower gear ratio would have required at lot of modification and likely a free spinning hub so that I could add a third pulley and second belt. Also every revolution of your motor brings it that much closer to the end of its service life. A motor that is run on average at 1/2 speed will last twice as long as the smae motor if it runs at full speed all the time. I Mention the torque and comparing motors in my video because it would be easy to look at HP numbers and think that the treadmill motor is better but in some cases it is not. Gearing can be applied to both motors and is "something extra" calculating the torque values gives you a direct apples to apples comparison of the motors.
Very informative video. You lay things out very well.
How did you get two potentiometers for fine and course control? Are they different?
Paul
Thanks! This video goes over the fine and coars option czcams.com/video/04d0u1RJyXw/video.html Let me know if you have any questions
@@dazecars Daze, I’m not getting any replies from James at Clough42. I can’t find information about the servo motor he used. His link to eBay is no good.
Do you think his ELS would work with a treadmill motor upgrade with your SCR variable speed controller, or is the VS redundant?
What do you know about the overall cost of his ELS and whether I can buy parts from him?
Sorry to bother you with another guys channel but I’m stuck.
Paul
@@paulmanhart4481 I'm happy to help!! Clough42 is a busy guy with tons of subscribers so I am sure he gets a lot of questions. When I have contacted him some times it takes a while for him to get back to me. For me the treadmill conversion was required to install the ELS. things happen quickly when threading at 100 RPM I can't imagine what it would be like if I was trying to thread at the 500 RPM ( the minimum speed when my machine didn't have a treadmill motor and yopu adjusted the pulleys to change speed). The entire ELS cost me less than 300 but that was before the inflation monster. I used slightly different parts than he did because of the dead links. I purchased the two control boards from him that you get on eBay and then the rest from amazon and TI, here are links:
Encoder amzn.to/3Z6Ymzy
Stepper motor/driver kit amzn.to/3Q7aKLN
Stepper Power supply amzn.to/3IAGur1
TI board www.ti.com/product/LAUNCHXL-F280049C/part-details/LAUNCHXL-F280049C
Clough 42 parts www.ebay.com/itm/164781208092
Please don't hesitate to reach out if I can be of further assistance.
@@dazecars So you used a stepper instead of a servo motor? They make closed loop steppers and I’m wondering if they would work the same as a closed loop servo. Maybe more noise.
Thanks Daze.
@@paulmanhart4481 That is exactly what I am using, a closed loop stepper and it works very well. It is what I am using in my ELS video
Cool video, I'm just about to do this conversion to my Lorch precision plain turning lathe (circa 1910-1930). I'm currently looking into braking resistors, which are quite easy to add to this kind of setup, with a DPDT relay (or in this case, two DPDT relays, one for direction, one for power supplybraking resistor).
Any thoughts on this?
And how about the need to remove the flywheel? I figured that the extra rotational inertia would be good to even out the speed when cuts are being taken.
Thanks!! I have a 3 videos series on braking resistors for my lathe. It’s fully automatic and engages when I cut the power or go to “neutral” on the direction switch. I used the flywheel on my mill for extra rotating mass but removed it on the motor for my lathe because the 5” chuck acts as flywheel mass.
@@dazecars I was going to ask the same question about the flywheel. Did you remove it with a gear puller?
@@nigel-matthews Flywheel on mine was simply threaded on. It took a bit of doing to crack the factory loctite, but not impossible. The spin-it-up-and-grab-it-with-gloves trick didn't work and I ended up removing the plastic fan on the opposite end, puting the now-exposed shaft into the vice, yanking on the flywheel pulley, then putting the fan back on.
@@daxliniere interesting. I’ll have to try that. Thanks!
@@nigel-matthews The flywheels that had a keyway and set screw I was able to tap off with a dead blow hammer.
I have a HF 44142 lathe and I picked up a Nordic Track and harvested a MC2100LS & 2.8hp motor. Being a PWM controller supply is this still a good candidate for re-powering the lathe?
it will work but is not my first choice because the MC2100 is fragile. Here are a couple videos where I used one and then after it fried. czcams.com/video/pAGfRHpHa-0/video.html and czcams.com/video/yMkW2SXl_sA/video.html
Hi, what is the small unit driven by the flat belt above the spindle.. (RPMs)?
That is the encoder for the ELS czcams.com/video/47Xyfnvqpes/video.html
haven't checked the comments so not sure if someone else said it yet, but horsepower can absolutely be measured with a wattmeter. One horsepower is exactly 745.7 watts
Thanks for info. I’m sure you probably need to load the motor to max watts?
You should do a video on making a power supply for a 240v motor. I have a 240v 4 hp treadmill motor that would be a beast but I've never seen a 20 amp 240v variac
That is very simple. Use an SCR setup like I talk about in lots of my videos and hook it up to 220. That will allow you to use the motor no problem
In your video you talk about pulleys and in the way you did it “was a bad way to go”. I’m just in the process of setting up my lathe/ mill (identical one to yours) with the same tread mill motor. Have you made any changes to the pulleys since? I’ve got everything wired the same as yours and it does what it’s supposed to. Thank you for your videos. I just tore apart my 7th free treadmill.
Not sure what you are referring to as "bad way to go" other than my one size fits none approach to speed BEFORE I went variable speed. Mine is currently geared at 5:1 because I make some high pressure cuts and the lathe doesn't even bog down. I never have much need to go to the speeds that a different ratio would afford me. If you have any other questions, please don't hesitate to reach out.
I lost my last comment. But what’s the box beneath your rpm meter? Cable going in and labeled rpm and feed.
Thanks,
Paul
that is controls for my ELS. I converted my non threading machine to be able to thread. czcams.com/video/47Xyfnvqpes/video.html
@dazecars Amazing content!!
I am the recent parent of a second hand Grizzly G8688. The controller is no good. Bad microcontroller chip on the pcb. Would this SCR setup suffice as an option to get the mini lathe up and running?
Motor Specs: .75hp, DC110v, 3 Amp
yes an SCR with rectifier and choke would work well for that DC motor.
@@dazecars Thank you! Filling the Amazon cart now with all of your recommended parts and pieces.
Let me know if any other questions come up or if I can be of any further assistance. @koriwright9135
I have a thread mill in working condition and I do not use it and want to dismantle the motor and the control circuit and use the control circuit as well as the motor in my mini wood lathe please advice
I have tones of content on my channel on doing just that. I recommend you spend som time watching. I am happy to answer specific questions as they arise but most if not all of what you need is already in my channel content this playlist has a lot of good info czcams.com/play/PLg4j6XzBdSY_83r86goaHonVUjoKsnIJM.html
Dang that open/unloaded chuck at 1500rpm was freaking me out. Great vid though, thank you for sharing your knowledge!
That is a myth. As long as the chuck uses a worm gear to move the jaws (witch 99% do) there is no risk of the jaws coming out unless you were on the last tooth. The is why people use worm gear drives, they are for when you want to spin something from one input but not have any pressure from the other output cause rotation.
On you wiring schematic it shows a “phone charger power for rpm”. How does that work please?
it's not a phone charger, its a power supply for a household item. It is DC and had the correct voltage to power the RPM meter.
I’m converting a treadmill motor into a tablesaw motor. I have the motor and that’s it. I need a potentiometer, a choke and a switch and what else.? And let’s say I didn’t need/want speed control, just a switch, what’s the easiest way to get my saw running, what are the necessities.?
My first question would be why? If you don't need speed adjustment there is no reason to use a DC motor and using an AC motor would be a whole lot easier. The next thing is setting up the DC motor is not as simple as "a potentiometer, a choke and a switch" you will need some sort of DC power supply. To correctly set up a power supply especially a fixed one I would need more information. What are the specs on the motor you are using? in other words what is the voltage rating and what are the max RPMs? What RPMs are you wanting the motor to run at its fixed output, and are you going to be doing any gear reduction?
Daze. What is the box you used to hold all the electronics? I like that it has a key lock and hinge.
Paul
Here you go. There are three I use:
This is the hinged box
amzn.to/3jPndaR
This is the medium size box I used in the power supply mistakes video
amzn.to/3Qe2edL
This is the larger box that holds all my ELS components
amzn.to/3Imerv6
@@dazecars Daze, I can’t tell you how much it means to me that you are helping. Someone like you, full of talent (probably a brain surgeon) and always busy takes the time to help mere mortals on the ground. I’m an optical physicist but am lost when it comes to electronics.
I have everything I need now. I’ve decided to use my Lieli 4.25 hp treadmill motor based on your torque calculations. I have a push button switch with a separate light to indicate power. I have my SCR, circuit breaker, bridge rectifier, DPDT switch, my big ass DC choke, an rpm readout, three potentiometers (100k, 50k, and 20k just in case). I need to measure the resistance the way you did to know which ones to use.
Once I do this to my Jet 1014 midi lathe, I will start thinking about doing it to my Southbend 10L metal lathe. Repeat the process and then put in the ELS.
I have a 9 Nm closed loop stepper motor and the same little servo that James uses. After that, I’m lost again. I’ll need to purchase the stuff from him, especially the software. He’s really gone all out on his ELS. Superb videos, but he lost me after video 7 or something.
Thanks again for your help Daze. Let me know if you ever have an optics problem.
Paul
@@paulmanhart4481 I am just happy to help!! not a brain surgeon, just a self employed maker of classic car parts with an electrical aptitude, enough to make a hobby with it. I have set up the clough42 ELS twice (on my machine and a spare system in case I ever fry something) so if you have questions when you get there don't hesitate to reach out an I will help if I can. The only thing I ask in return is let other know about my channel. There is so much... for lack of a nicer word, "low quality" video on youtube that it has been a real struggle to get the youtube algorithm to suggest me to viewers. In fact when I do searches my self google finds me better than the CZcams search function. To fix that I need more likes, more views and more subscribers so if any of what I am doing applies to some one else please provide them a link to my videos and or channel. Thanks!!
@@dazecars Hi Daze. I wrote a long message to you but I don’t think it went through. Basically I said…
I want to have two separate boxes. One for the electronics mounted on the wall and one for controls mounted on the lathe.
Electronics box includes
1. SCR
2. Toroid
3. Bridge rectifier
4. Circuit breaker
5. Big ass dc choke
6. 120 vac muffin fan.
Control box includes
1. On off push button with indicator light
2. Two potentiometers
3. Digital rpm display
4. DPDT forward and reverse switch with green indicator light for forward and red for reverse.
There seems to be two issues.
First is the number of wires going from control to wall box.
Second is that the rpm meter is dc. I either need to convert ac to dc in the control box, or use a dc power supply. But then I can’t slave it to the lathe being on and off.
Your comments are welcome.
I’d like to send you a sketch of what I envision but I can’t see a way to attach photos here.
Thanks,
Paul
@@paulmanhart4481 If you contact me through my web site you can email me with photos. If you watch my RPM meter video I powered My RPM parts with treadmill parts. Your setup doesn't sound that much different than mine except I also have a box with ELS components. Mounted in the cavity of my lathe column are my controls, master power, forward and reverse and two speed controls. In my power supply box is the SCR, the inductor, the rectifier and the circuit breaker. My choke is so big I mounted it blow the power box.
How many hours can a treadmill run when in use?
In theory non stop. Heat is the only concern. As long as it is setup with the correct cooling fan as either part of the flywheel or external on the shaft and is geared so it is still producing decent motor RPMs at the desired machine speeds it will only get warm. If a person wanted to run it for long periods of time at the slowest motor speeds an external cooling fan not related to motor RPM would be a good idea.
What DRO are you using on your lathe?
Came from eBay. I went with this seller because it was mix and match. I was able to order each individual piece to get the correct length scales rather than a ready made kit where nothing fits correctly. Used the same supplier for my mill build as well
www.ebay.com/itm/392899229040
Hey pal. I’ve watched 12-15 of your videos. Yeah I’m amazed.
Question….what kind of stuff are you making? Looks to me you have made a hobby of pimping this lathe. And I commend you with the highest praise. BUT what kind of stuff are you making? Anything fun?
Its all fun to me 😁 I make stuff all the time but not anything worthy of a CZcams video. I am a fabricator not a machinist so most of what I am machining is to either repair an existing part, make something I have better, or a small section of other projects, heavy on fabrication skills. I use the lathe all the time to extend the threads on a 4.5" grade 8 bolt for one of the products I sell through my business. I used the mill to make the dog tooth gear, in my mill power feed video and other little projects like that as they come up but nothing to the level of most of the proper machinists already on CZcams. I will be making a new leadscrew for my lathe in the future and maybe a half nut for it but that comes back to the category of "pimping this lathe"
@@dazecars well you keep doing what you’re doing, you’re keeping me very entertained!! I feel like I should share this much…. I’m simply a hobbyist and have a mill lathe combo I bought used in a non working condition. I’ve always been intrigued with metal work. Especially machining. The lathe works but the mill motor went bad. I tried to salvage it but under no load it started smoking and was pulling 8 amps. I’ve been on the hunt for a replacement motor for about a year! So I’m going to take all of your advice and go with a treadmill motor. Shouldn’t be too hard for me to find one, my next-door neighbor is a professional scrapper. You wouldn’t happen to remember the brand/models treadmill hold a desirable motor?
@@dathonlawler81 The brand make and model I always look for is FREE. Treadmills are one of those things people don't want to move because they are big and heavy so people will give them away rather than deal with moving them. I picked up my first treadmill about 3 years ago and have scrapped 18 in that time. I have a search set up on Craigslist and Facebook market place. Every treadmill I have scrapped has been different. I never know what I am getting until I get it home and get into it. They all have good usable parts some are just better than others. If you can be patient and the treadmill is free you have nothing to loose. BTW I started a facebook page for mill lathe combo owners, you should come join us facebook.com/groups/168134035160655
@@dazecars yes sir. I already did join. You approved me the other day. I was surprised when I learned you were the admin, and I assume creator!! I’m a crane operator so I sit and watch videos non stop at work haha. I’ll let ya know how my progress comes along. Thanks for such quality videos. You have a pretty good following for being new-ish. I’m gonna bet you’re gonna really blow up on views here shortly. Your videos are put together very well. Good angles, good lighting, not too close or too far on the zoom. Explanations are in depth and understandable. Superb speaking voice too.
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Can I use a treadmill's original controller to use the motor?
take a look at this and let me know if you have any other questions czcams.com/video/u-mBcI-CDe0/video.html
Would a 7812 IC voltage regulator help any at the end of the circut?
No for two reasons, first most of those ICs are not able to handle more than 5 amps and these motors are 15-25 amps. Second that voltage regulator will provide 12V. That means as you try to change the voltage to vary the speed nothing will happen as it will spin at the constant 12V speed.
Thank you! Suggestions to where to source the larger chokes?
@@garymullens650 Here is some guidelines to help you. First of all bigger is better. I have several motor chokes ranging from the size of a tennis ball to the size of a soft ball and the bigger they are the better they work. Second the wire for the choke needs to be a minimum of 16 awg. If the wire is not that big or better it will not have the amperage capacity to allow the motor to work properly. Third they are not available on Amazon at least not inexpensively, there are a few privet sellers on Amazon selling used parts for big bucks but the generally available chokes on amazon are too small because they are not designed for a motor even though they look correct in the picture in the picture they are way too small. The choke in most of my videos is part number 130993. Instead of getting one new I would get a used one. A lot of treadmills come with a choke. Go to eBay and search “treadmill motor choke” BUT know that most people on eBay don’t know what they have and the word “transformer" will also appear in most listings. Problem is a choke and a transformer look almost identical so some listings are for transformers and some are fore chokes because the sellers think they are interchangeable. They are not. They would only be interchangeable if you modify a transformer to work as a choke. (see my DIY choke video) To tell the difference count the wires. A choke will only have 2 wires, a transformer will have 3 or more. Also before I started doing videos chokes on eBay could be had for $25 or less shipped but now that more people are looking for them (due to my videos) the eBay sellers have raised their prices quite a bit. Your best bet might be the DIY option out of a Microwave transformer. Please let me know if I can be of further assistance.
Thank you for the detailed response. Please keep the videos coming! Ill keep searching the ads cor treadmills.
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Do you find that the lowest speed(50rpm) still has the torque necessary?
That is the nice thing about a DC motor, the torque number is the same through the entire RPM range with the exception of the very lowest speed. I singe point thread grade 8 bolts all the time to double the length of the factory threads and I do it at about 70 RPM. It doesn't slow stumble or bog, BUT I am using a quality treadmill motor. There are lots of different motor configurations available but I would say they all fit into one of three categories. Cheap home treadmill, the motor usually has 1-1.5 foot pounds and can be run from 7000-10000 RPM requiring massive gearing. An expensive home treadmill which usually has 2 to 4 foot pounds of torque and an RPM range up to 4500 RPM. And then there is the commercial treadmills that have 3.5 to 5 foot pounds and a max RPM of 2500-4000 RPM. The motors on both my mill and lathe are medium quality from expensive home treadmills.
@@dazecars Thanks, that was going to be my next question. Many in my area for free on FB. Most are old Sears-types but there are a few that appear to be better quality home units like Nordic Track. Not that that name should impress but they appear to be larger and heavier. Their replacement motors online appear to be above the minimal DC types. Do you have brands that pique the interest? I suppose it's a bit of a gamble. Dragging these home just to break them apart doesn't enthuse the wife(nor myself) so it needs to be worth the junk parts I can salvage.
First of all I don't pay for them so even if I don't get as much good stuff I'm not out anything. People don't want to go through the effort to move them so they do come up for free several times a year. I search facebook market place and I have an automatic search on craigslist that emails me anytime a treadmill comes up. I have scrapped about 18 of them in the last 3-4 years and I never know what I am getting until I get it home. As a rule the bigger the machine the bigger the motor will be. A treadmill is full of good stuff. Even the smaller motors are good for a drill press or other similar applications. The tread deck makes outstanding shelving in fact the "work bench" I sit at for most of my videos is a treadmill track. Tones of uses for the incline motors, and then there is all the box tubing. Also the smaller treadmills tend to have the choke needed for an SCR. I can scrap one in about 30 minutes and its always worth the effort. Lastly when choosing a motor never go by HP numbers, always calculate for torque. @@836dmar
Excellent info. Thanks so much! @@dazecars
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I have old bench lathe myford and motor defective ,so i want to replace with treadmill motor which i already have ( 130v dc 6700rpm,2.5 hp) please help me to fix this trrdmill motor . Thanks
Is that 2.5 HP max or continuous? I ask because of the high RPM rating. That sounds like one of the smaller cheaper motors and if that is the case it would likely not be a good candidate for the lathe. czcams.com/video/KPcAr9orqZw/video.html
If you want to get full value of torque you will need an idler shaft to allow the treadmill motor to stay in its full power rpm
Torque is constant regardless of RPM with a DC motor. Yes you can gear it to multiply torque but it is not like and AC motor where you want to run it at max to get the best torque result. An AC motor as a torque curve and produces the best torque at the RPM it was designed to run at, but with a DC motor the torque is constant through the entire speed range except the very slowest speeds.
@@dazecars I found that the slower I have the treadmill motor the less power it has
I put one in a bandsaw years back and while it will cut and I can vary the blade speed for different material but it loses power the slower I run it
An ac motor will run at a constant torque when you run it through a vfd but yes has a very definite torque curve when run through a potentiometer
@@jarredsegal6842 that may be your observation, but your conclusion is wrong. As I said before the torque curve for a DC motor is constant. I have three machines, all running treadmill motors, and I can run them at the slowest speed and I don’t lose any torque. Conversely, if I speed them up, I don’t gain any torque. I single point thread on my lathe all the time at 100 RPM and it’s super high tool pressure so a lot of torque is required and my machine doesn’t even bat an eye. Most likely the cause of your problem is the motor was undersized or the power supply was undersized. Torque is a function of amps and if the power supply wasn’t able to provide enough amps or the motor didn’t have enough torque to begin with, then you would have an issue at lower RPM where the extra revolutions would help compensate at higher RPM. Again I understand those are your observations but I know what I’m talking about the whole reason you use the treadmill motor for these kind of upgrades is DC motors provide just as much torque at low speeds, and you can vary the speed where an AC motor requires a VFD or a pulley system to vary the speed.
More video please
I will do my best 😁
I all ways put something in my chucks tight before spinning, my gisholt has 28-inch swing. safety first,
The jaws are driven by a worm gear so there really isn't any way for centrifugal force to pull a jaw unless it was barley held. That is the advantage of a worm gear, it locks in one direction. With that said it's not much effort to chuck something even though it's not needed.
Watts are a measure of power the same as horsepower. Also, it can be run with a VFD no problem..
A VFD is way more expensive and most require a 3 phase motor.
Dear brother iam inspire watching your video can you help me and Iam how to change ac motar convert dc motar lath machine please help me how to iam making DC converter box
I have lots of videos showing how to set up a power supply
Another great video except for one glaring "detail." The torque value should be calculated at the spindle speed instead of the motor speed. As an example, if I convert my lathe to a treadmill motor it will be geared to the same top speed that it has currently which is 2500 rpm. In your first example the 4000 rpm motor geared through a toothed belt and pulleys would produce 6.3 foot pounds of torque. In reality, the existing 1 hp motor on my 11x 26 lathe has enough power for the kinds of work I do on it so the new torque rating is not that important. My goals would be to reduce the 150 rpm minimum to about half of that and maintain the peak rpm at around 2500. The big added value is not having to fiddle with belts and pulleys to change speed. After 15 years of amateur lathe and mill work I've finally started referring to speed calculators for best rpm data. Being able to dial in the RPM with a knob is a huge improvement. It just needs to be FULLY calculated to know if the proposed replacement motor has enough power. In your second example the 6700 RPM motor geared to a realistic speed, using my machine's 2500 RPM again, the true torque is more like 5.25 foot pounds. Only a very narrow target use would require a 6700 RPM spindle speed.
I appreciate the comment and totally get what you are saying. Yes final spindle speed and torque numbers are important BUT it was not a glaring detail. Not all treadmill motors are created equally and you must know what you are starting with to find out if it is even in range. Most guys are replacing their AC motor with a treadmill motor and retaining the existing gearing. The motor calculations give you an apples to apples comparison to find out if the new motor even has the potential to work. I have had a ton of people reach out because they go with a cheap treadmill motor and can't figure out why its not working well even though it is way more HP than the original AC motor even with gearing. With gearing a lessor motor with higher RPM max can be made to function the "same" as a better motor with the lower RPM rage but all those RPMS are going to translate into shorter motor life, more heat (this is why high RPM treadmill motors usually have blue wires) and an inferior system for the long run. Starting with a direct comparison avoids those problem and THEN you can use the gearing calculation to dial things in, adjust RPM range and torque so yes it is important...very important, but beyond the scope of this video.
Also can this tach sensor input on the 2100LS supply be used for speed read or control?
That is there to maintain motor speed under load not for a readout.
Your math implies that at zero RPM, Tesla motors develop zero torque. What am I not understanding here?
It's actually a null set because you can't divide by 0. First of all an AC motor has a torque curve and max torque is usually at designed RPM. HP has always been a calculation TRQ * RPM/ 5252. So a motor with 4 #Lbs and 0 RPM would produce 0 HP because the motor is not spinning and HP is the ability to do work but the torque is still there. But all this is dependent on the torque curve. That is one nice thing about DC motors after initial startup speeds the torque curve is constant.
Please stop saying "rpms". RPM stands for "revolutions per minute". RPMs means "revolutions per minutes". How many minutes? It is ambiguous and meaningless and drives engineers like me nuts.
I appreciate the comment and you are completely correct, but it is not likely to change. Don't get me wrong I too prefer accuracy but I am also creating these videos off the cuff and a lifetime of making RPM plural(er) 😂😂 is not a habit that will easily brake. Also adding an s to RPM is very common in the vernacular all-be-it inaccurate. 20 years of using RPMs in a fairly public way for both my automotive interests and now my machining interests and you are the only one to ever point out the error. Again I really appreciate the comment and will try to take it to heart but the practical application is not likely.