How to repair sparking commutator | damage armature repair 

2:14 commutator is black because fine debris is sucked into the motor when it is cutting things. The electric current burns this debris into a hard shiny lacquer on the commutator and the brushes. 2:35 wire holds gearbox shut, keeps grease inside while cleaning commutator 2:50 use very fine grit emery cloth to remove black gunk from commutator. it is for the best if your fine grit emery cloth loads up immediately and you need to use a lot of it. Emery cloth is easy to replace but the commutator is not. You want to minimally strip away copper because you probably can't rebuild this kind of commutator when it wears down. Probably a crimped and stamped assembly with non-replaceable commutator segments. 3:16 fine pointy tool is used to scrape between commutator segments. It's essentially the same descaling tool dentists use to clean your teeth. The burned debris removed by the emery cloth also wedges down between segments and can electrically short them out, reducing motor torque. Don't dig too hard or deep because there's usually either plastic or mica insulating the segments. 5:30 using a steel blade to bevel and deburr edges of copper segments so that the brush doesn't dig into the slot between segments. (Though I've not seen much discussion of copper segment edge beveling/deburring in engineering textbooks, so unknown if this practice is advisable if not already present in the original design.) 6:30 scraping the shiny burned debris off of the face of the carbon brushes. (Though note, brushes cleaned this way are flattened and are now smooth on the face, but the commutator surface is curved. When reassembled, initially only the center part of the carbon brush makes contact with the curved commutator. Current flow is reduced and the motor will initially have reduced torque. The motor needs to spin for a while to wear the carbon brush face back to a curved profile that fully contacts the curved commutator segments. If you can get new brushes from the manufacturer that are preshaped at the factory to be curved to fit the commutator [and you install them properly oriented] then you can have full current and maximum torque straight out of the package.) 11:08 Try to avoid having the cat get its tail caught in your power tools.

nice! I just got into rebuilding a starter. Although I used a wire brush to buff the commutator I did not use a pick on the lines between the contacts. Will do that now before final assembly. I used to rebuild starters and used a broken hacksaw blade between the contacts. The starter I'm working on has spaces to small for a hacksaw blade but a pick will do. Thanks

I don't have this kind of tool on hand yet it would be helpful to me the way how it is being repaired if I encounter the same issue in the future.

Thank you very much sir ji. plan for success.

thank you very much for this video i have the same problem. thumbs up .

Thanks to the good idea I have learned from you

show de bola ficou top

Good job, sometimes you can do it from outside, just take old cutting dics, brake it and polish place where you have spark

Great job 👌👌

Very useful informative video Tq

Good idea🎉🎉🎉

...based on my observation. Bearings: front and back side are misaligned causing wiggled in the armature assembly with spark between cummutator and brushes that damaged both.

God job

My angle grinder has that very problem. When inspected, the copper part where brushes make contact is worn, Can it be filled? And how? Please help.

hello sir. i don't understand how to find the start or first winding on the any armature commutator. Please help

Good job. Only it needed new brushes, the old one we're almost out.

I was looking for a tutoring of repairing a smoking electric mini saw. I like Kevin MacLeod music. What is the name of it.

Is it important what sandpaper to use? What grid did you use for comutator and what for brushes? I replace brushes in hair clipper but it's very loud since.

Mechanical engg students should watch this type of useful videos.

Great vid. At the start was there a burning smell as well as sparks? That’s the way mine is even after changing the brushes.

Hi I have the same problem whit a Sáez all can I do the same job ??

Good job

Perfect work

Mere drill machine me maine yeh sab kiya carbon brush bi change kiya, field core also change, after that it's continue sparking.... Now what to do?

the sparking is caused by abuse, overloading/dirty air,,, very important to cut out between overheated shorting commutator bars

I tried sanding the commutator and brush, and cleaning between bars but my new saw still sparking. Any suggestions.

Jeśli będzie uszkodzony konwerter to żadne czyszczenie nie pomoże i tak będzie przebicie a w tedy nie pomoże woda z Wisły jak jaja obwisły.

@ commutator is black because fine debris is sucked into the motor when it is cutting things. The electric current burns this debris into a hard shiny lacquer on the commutator and the brushes. @ wire holds gearbox shut, keeps grease inside while cleaning commutator @ use very fine grit emery cloth to remove black gunk from commutator. it is for the best if your fine grit emery cloth loads up immediately and you need to us

sir. no po problem ng circular ng sparck

I replaced rotor berings brushes and still have big spark. Why?

I have a 7in Diamondback wet saw that recently stopped working. I fixed it once before by cleaning the armature but tried again to do the same.. nothing. Probably fried right?

If a copper bar or 2 is damaged (melted) will it still work?

Great video-thanks! I have an old B&D bench grinder that suddenly stopped while I was using it...hard! It got pretty hot. Now it just buzzes. When off spins freely but turning it on magnetized it and locks it in place. Any ideas? Brushes? Thank you.

👍

Hello from iraq my motor similar

Hi Brother. Can you show me how to fix spark and smoke from my drilling machine

Very slow but good

❤

That will work temporarily.

Sir vlog mo nmn sunod kng paano ikabit ang stator ng drill sa carbon brush..yung parang spring na sinasabit sa ilalim.kc pinasabit ko lng dto sa nag gagawa siningil ako 250.cncya na sir baguhan lng

Gud day sir ask k lmg bakit malakas un vibration nga cut saw ko anu kaya posibling sira

Ok felicitar

so we need to change the brushes and clean it

WOW - I got sparks coming out of my petrol weed wacker.

Sir, may bagong bili po akong Mailtank circular saw. Upon testing, anlakas po ng spark at amoy sunog agad. Wala naman pong usok pero everytime na ipepress ang trigger, malakas ang spark at amoy. Normal po kaya yun dahil bago pa ang brushes nya? Thank you and more informative videos pa po.

Where is dealer and supplier of DeWalt machine in Uganda

Goood

Nabasa Po Ang cut off machine namin at pinaandar pos tumigil may paraan Po bang maayos

Sir tnong klang xe ngspark yong jigsaw ko khit nasanpaper kn at bgo yong carbon gya ng ginagawa sa video

Ok

Ganyan din boss circular ko lakas din mag spark ganun din ba sira nun. Salamat

Unplug it before working on it

Can't work out on how many times he cleaned the armature, sanded ,scrapped and cleaned again, sorry have to go to bed now got tired of the same thing

PLEASE HELP ME SAND PAPER GRID HOW MUCH THANKS?

Boss saan po makakabili ng armature

That's not good....better to repkace armature..

Sir tnong klang pareho ba ang armature ng cercular at grinder

Taga saan ka sir? Nagagawa din ba nasunog na armature?

like 2000 ads how is it possible

The cluster and n

Shoot mine is throwing sparks out

Good morning sir kpg midyo malakas ang spark dilikadoba

Please .... !!! The musicis unnecessary and gives the viewer a migraine

Gin try ko....indi na Wala Ang spark nya

Tried three time in a row to replicate your guide carefully on a burned vacuum cleaner motor. No luck. The sparks and smell are still there. Can't see any other problem. Probably this motor is really burned out.

Boss ginaea ko na yan pero nag spark parin

Bought a table saw, commutator failed. Melted. Abusive owner I suppose. I wouldn’t label this as repair. This is simply cleaning.

How to clean not repair

Didn't see any damage or any repair ------ just armature clean and buff .Pretty deceptive title

That temporary and worst method.

Are you a profesional technician???or you are only getting subsicriber so that you get money from you tube????do not do that men!!youre fire!!!

Anu tawag dun sa dalawa itim n may spring