This may not be strictly related to this video, but in India, working on old motors is definitely not a lost art. You'll see guys sitting around on the sidewalks replacing windings on old motors by hand. Pretty neat. Thanks for sharing this. Very interesting!
Tubalcain, you saved my linear actuator! It's a part on my wood boiler that closes the damper, and stopped operating correctly. I pulled it apart, and couldn't at first see anything wrong with it, no loose wires, brushes looked fine, etc. Then I started examining the commutator and since I watched your video I knew that the copper segments must be electrically isolated from each other. The brushes had worn burrs on the segments so they were shorting against each other. Well, I don't yet own a lathe, but plan to soon, hence the reason I've been watching your channel. However, this is a tiny commutator, and it turns out the shaft fit just perfectly in my dremel tool. I ran a small screwdriver between the segments to raise the burr, and then sanded it by hand on my "dremel lathe". I had to repeat to get all the burrs removed, then I finished with a gray scratch pad. Put it back together and worked perfectly! It's a $75 part that probably would have been in the trash bin had I not watched this video. Thanks Tubalcain!
+mrpete222 I would love to see a demonstration of how to hand wind a motor if that's something you would be willing to take on. As others have commented this is still done in the third world countries, but it's just a mystery to me.
+mrpete222 Details...details. You know you want to! Even without the hand winding, I'd like to see you teach a video on electric motors, similar to what you did with the 4 stroke and 2 stroke engines. Most of us know the principles of how they work, but I always end up with a better understanding after watching your vids.
@DairyNZ Yes, both ways would work. Also, try holding a brass bushing of the appropriate size in a regular jacobs tail stock chuck. This would support it.
having never had an undercutter I have always started by undercutting the mica by hand using a bit of hacksaw blade or scalpel blade ground to a slight hook and the right width before doing anything else to the com. I have usually found there is just enough of the original undercut to help guide the tool and if I do slip I'm only marking a surface which is being taken off anyway. If you don't have an armature chuck you can turn a close-fitting bucket for the end of the shaft with a centre drilling so you can support the armature at the tailstock end with an ordinary centre.
I did this on a couple of brush motors and ended up with a nice, solid copper tube where the commutator was. My guess is that I ran it too deep a cut or, as you point out, the tool wasn't sharp enough. It melted the copper over the comm lines and it was fun trying to dig those up. Next time I will grind it instead. BTW, there are still a huge number of brush motors out there so this video is current and helpful. Thanks!
it involves using some thin scraping device like a hacksaw blade to lower the mica separators between the copper segments. They can interfere with the brush connection to the copper segment if the mica is protruding.
I shared this with Tom Lipton at OxTool. He had a recent video where he was horse trading and came upon a Jacobs No. 100 Chuck and had never seen one before. For what it is worth, I would like to see a video of somebody who knows what they are doing (you) use the mica undercutter. A friend recently gave me on to fit my old Atlas lathe. Pretty sure I could make it work, but don't relish the mountain of sacrificed blades and rotors the endeavor may generate.
there's always another way to do a job The way he's got it set up is a good way to do it. Sure you could use a four jaw on the Comm end dial it in as close as possible and turn from there Either way works NICE VIDEO Pete Thank you
I'm going to be doing this to my Asian lathe DC motor so the video is very relevant! I actually have an old atlas mica under cutter I acquired but I don't have the brass jaw Jacob's chuck. I wish I did. Thanks for the video.
It is the process of removing a very small amount of the mica that insulates each of the commutator segments from one another. The idea is to make sure that the mica is countersunk (1/32" I believe) just below the surface of the segments. If this isn't done the mica could actually slightly lift the brushes off the commutator. Not a good thing! There is also a finishing procedure to remove ridges from the segments created by this process.
Yes--copper is bad. No magic answer. Machinist book calls for these angles on bit. Refer to my video on lathe bits where I discuss angles. front clearance 7 degrees, side 7, back rake 10, & side rake 25. Cutting speed 75 - 150 fpm. Radius on tool tip of 1/32".
I am curious how you go about cleaning the armature and the field coils? could you let us know :) I am rebuilding a henry J delco remy. its well seasoned inside with grime.
I noticed that your Clausing lathe makes the same racket as mine at work when the motor is disengaged....I wish there was a way to fix it without taking the clutch assembly apart.
copper is annoying to turn! I was boring and threading copper and copper pipe for some plumbing and it comes off very messy. got any tips because i have 20 more pieces to do!
Could you chuck it from the other end closest to the commutator? Or use a fixed steady, don't have a brass jawed chuck. Every year I need to replace the starter motor in one or more of our quad bikes with a reconditioned one. Being able to change the brushes myself would save me big $.
Mr. Pete, Is the armature part itself ever machined, or any need to? I have a general motors window motor here, There must be a little wear somewhere, and is running ever so slightly eccentric. I know the motors are cheap on e bay, (maybe not good quality either, the inexpensive ones,) But I'm just trying to nurse this car along maybe another year, till I get some other things paid up. There are "witness marks" and some wear on the armature itself. I just wondered if I could machine the armature itself, Just about an inch off the length of the armature , to stop the slight knocking, and possibly eliminate some slight friction? It is an 2002, Olds Alero, 4 door. This is the passenger Right front. I already replaced the regulator and motor on the drivers side, with a cheapo $30.00 e bay one, (So Far, So Good???) But Right now, I have more time than money, and need to save $$ as much as possible. (Note; The motor does run) Just want to get it operational, as the inspection mechanic let it "slide" last time, But mentioned he wanted me to fix it for the next inspection. (Coming soon, end of April)
I work for Siemens repair shop and best way to turn commutator is using clean varsol..it is a very good cutting agent .just blow dry and good to go.. This is used on all voltage armatures including 600 volts.
![Lp. Сердце Вселенной #30 ДВА В ОДНОМ [Один человек]• Майнкрафт](http://i.ytimg.com/vi/nrXy15orKhY/mqdefault.jpg)
This may not be strictly related to this video, but in India, working on old motors is definitely not a lost art. You'll see guys sitting around on the sidewalks replacing windings on old motors by hand. Pretty neat.
Thanks for sharing this. Very interesting!
Tubalcain, you saved my linear actuator! It's a part on my wood boiler that closes the damper, and stopped operating correctly. I pulled it apart, and couldn't at first see anything wrong with it, no loose wires, brushes looked fine, etc. Then I started examining the commutator and since I watched your video I knew that the copper segments must be electrically isolated from each other. The brushes had worn burrs on the segments so they were shorting against each other. Well, I don't yet own a lathe, but plan to soon, hence the reason I've been watching your channel. However, this is a tiny commutator, and it turns out the shaft fit just perfectly in my dremel tool. I ran a small screwdriver between the segments to raise the burr, and then sanded it by hand on my "dremel lathe". I had to repeat to get all the burrs removed, then I finished with a gray scratch pad. Put it back together and worked perfectly! It's a $75 part that probably would have been in the trash bin had I not watched this video. Thanks Tubalcain!
+Jon Logan Thanks for watching---glad I helped. Watch all 500 of my vids
+mrpete222 I would love to see a demonstration of how to hand wind a motor if that's something you would be willing to take on. As others have commented this is still done in the third world countries, but it's just a mystery to me.
+Jon Logan Never done that
+mrpete222 Details...details. You know you want to!
Even without the hand winding, I'd like to see you teach a video on electric motors, similar to what you did with the 4 stroke and 2 stroke engines. Most of us know the principles of how they work, but I always end up with a better understanding after watching your vids.
+Jon Logan I am presently working on a video---where I make a small motor/generator. I will wind the tiny armature --watch for it.
You could always use an oilite bushing to match the shaft and clamp it in the tailstock chuck just enough to keep it steady.
@DairyNZ Yes, both ways would work. Also, try holding a brass bushing of the appropriate size in a regular jacobs tail stock chuck. This would support it.
mrpete222 is that chuck spinning or stationery?
having never had an undercutter I have always started by undercutting the mica by hand using a bit of hacksaw blade or scalpel blade ground to a slight hook and the right width before doing anything else to the com. I have usually found there is just enough of the original undercut to help guide the tool and if I do slip I'm only marking a surface which is being taken off anyway. If you don't have an armature chuck you can turn a close-fitting bucket for the end of the shaft with a centre drilling so you can support the armature at the tailstock end with an ordinary centre.
The 'close fitting bucket' for the end of the shaft is a great idea! Thanks.
I did this on a couple of brush motors and ended up with a nice, solid copper tube where the commutator was. My guess is that I ran it too deep a cut or, as you point out, the tool wasn't sharp enough. It melted the copper over the comm lines and it was fun trying to dig those up. Next time I will grind it instead. BTW, there are still a huge number of brush motors out there so this video is current and helpful. Thanks!
it involves using some thin scraping device like a hacksaw blade to lower the mica separators between the copper segments. They can interfere with the brush connection to the copper segment if the mica is protruding.
Dude.......that was a bad ass video. I am an aircraft mechanic and also machinist. That was very cool. Thanks for sharing!!
👍
I shared this with Tom Lipton at OxTool. He had a recent video where he was horse trading and came upon a Jacobs No. 100 Chuck and had never seen one before. For what it is worth, I would like to see a video of somebody who knows what they are doing (you) use the mica undercutter. A friend recently gave me on to fit my old Atlas lathe. Pretty sure I could make it work, but don't relish the mountain of sacrificed blades and rotors the endeavor may generate.
Don
Sorry, I do not own an undercutter. I usuallu just hold the hacksaw blade by hand--usually resulting in some nasty scratches.
there's always another way to do a job The way he's got it set up is a good way to do it. Sure you could use a four jaw on the Comm end dial it in as close as possible and turn from there Either way works NICE VIDEO Pete Thank you
I'm going to be doing this to my Asian lathe DC motor so the video is very relevant! I actually have an old atlas mica under cutter I acquired but I don't have the brass jaw Jacob's chuck. I wish I did. Thanks for the video.
It is the process of removing a very small amount of the mica that insulates each of the commutator segments from one another. The idea is to make sure that the mica is countersunk (1/32" I believe) just below the surface of the segments. If this isn't done the mica could actually slightly lift the brushes off the commutator. Not a good thing! There is also a finishing procedure to remove ridges from the segments created by this process.
Watching this in 2021 because my new to me SB9C came with a Mica Undercutting attachment. I knew you'd have something on these methods.
My dad left me his lathe just for this plus his growler
I learned how to rebuild them in his shop at 12 years old
Awesome, I didn’t learn to do this till I was 15
Yes--copper is bad. No magic answer. Machinist book calls for these angles on bit. Refer to my video on lathe bits where I discuss angles. front clearance 7 degrees, side 7, back rake 10, & side rake 25. Cutting speed 75 - 150 fpm. Radius on tool tip of 1/32".
I am curious how you go about cleaning the armature and the field coils? could you let us know :) I am rebuilding a henry J delco remy. its well seasoned inside with grime.
Thanks - I always wondered how this was done.
I work on medical equipment and this will be good for many years. I want to post on my web site.
I noticed that your Clausing lathe makes the same racket as mine at work when the motor is disengaged....I wish there was a way to fix it without taking the clutch assembly apart.
copper is annoying to turn! I was boring and threading copper and copper pipe for some plumbing and it comes off very messy. got any tips because i have 20 more pieces to do!
Good job just clean with hack saw blade
Could you chuck it from the other end closest to the commutator? Or use a fixed steady, don't have a brass jawed chuck. Every year I need to replace the starter motor in one or more of our quad bikes with a reconditioned one. Being able to change the brushes myself would save me big $.
Some of use still like to fix our own so this is great material!
What exactly is "undercutting" the micah? I've never heard that term before...
Mr. Pete, Is the armature part itself ever machined, or any need to?
I have a general motors window motor here, There must be a little wear somewhere, and is running ever so slightly eccentric.
I know the motors are cheap on e bay, (maybe not good quality either, the inexpensive ones,) But I'm just trying to nurse this car along maybe another year, till I get some other things paid up. There are "witness marks" and some wear on the armature itself.
I just wondered if I could machine the armature itself, Just about an inch off the length of the armature , to stop the slight knocking, and possibly eliminate some slight friction?
It is an 2002, Olds Alero, 4 door. This is the passenger Right front.
I already replaced the regulator and motor on the drivers side, with a cheapo $30.00 e bay one, (So Far, So Good???)
But Right now, I have more time than money, and need to save $$ as much as possible. (Note; The motor does run)
Just want to get it operational, as the inspection mechanic let it "slide" last time, But mentioned he wanted me to fix it for the next inspection. (Coming soon, end of April)
No, you cannot machine the amateur
OK Thanks Mr.Pete.
I'm going to just get a regulator/Motor Assby.
Thanks!
Interesting thanks
I work for Siemens repair shop and best way to turn commutator is using clean varsol..it is a very good cutting agent .just blow dry and good to go.. This is used on all voltage armatures including 600 volts.
12 years ago. Still work there? Have I generated a bit of nostalgia? 😸
Ok, makes sense.
ok
Start at about 4:30