Disc Grinder Restoration and Conversion - 110V to 20V by Rewinding
ฝัง
- เผยแพร่เมื่อ 20 มิ.ย. 2022
- Disc Grinder MG-125J
AC 100V 50/60Hz 8A
125 mm x 16 mm x 22 mm. 4300 m/min.
Power in 780W
Power out 480W
MITACHI
Tokyo Japan
I bought this tool from Japan recycle store without testing. When I use it, it does not seem to work well, because some bearings are broken. By replacing those broken bearing, this tool will work normal. But I want it runs with battery instead. As a result, I can do it.
Video sections
00:33 before restore testing
00:59 disc grinder blade removal
01:18 disc grinder disassembly
03:28 broken bolt removal
07:48 armature disassembly
10:04 commutator bar install
10:25 DC rewinding diagram 18V
10:29 DC armature rewinding
16:40 permanent magnet install
16:56 motor testing
17:26 carbon replacing
20:14 battery adapter mount
22:54 painting
24:48 battery disc grinder assembly
31:15 battery disc grinder grinding test
I hope you find this video useful and enjoy it!
Furthermore, I am happy to receive feedback, suggestions to improve myself.
!!! I'm sorry for the mistake if I did in this video !!!
Thank you very much for choosing to watch my video!
Have a nice day
Gear Show - แนวปฏิบัติและการใช้ชีวิต
![Cord to Cordless Circular Saw Conversion 220V to 20V [Rewinding]](http://i.ytimg.com/vi/k-L9mXOpwWA/mqdefault.jpg)
![Cord to Cordless Circular Saw Conversion 220V to 20V [Rewinding]](/img/tr.png)
NO high speed playback, NO music, WITH natural tool and workshop audio, THANK YOU!
Widzę że nie tylko mnie to denerwuje
@@Tomaszs9999 ,
@@Tomaszs9999 ,
Buen trabajo mi muchacho y muchos éxitos 🙏👍
@@user-fj1zl9ul1m😊
I can definitely feel my blood pressure go down every time I watch one of your videos, it's always very relaxing to watch someone doing something right.
I'm so glad it helps you. Thank you so much for sharing!
@@gear_show Ni
@@gear_show
L
In
@@gear_show۸۲۸حح ححح۸حح۸۸۷۸۲۲۲۲۲۲۲۲۲۲۲۲۲۲۲۲ح۸۸۸ح۸ححح۸ح۸ح۸۸۸ح
Sorry brother, you couldn’t hear me yelling at the screen telling you “Don’t forget the insulating paper!!!” That sucked but I bet you’ll never forget that again. It’s how we learn my friend, some lessons are easier than others…
Sweet restoration overall, I did enjoy watching. Thanks for taking us along and owning up to your mistake. Honesty is the best policy and with that you’ve made a sub out of me!
👍🏼👍🏼 from this guy!
@@tomgreen4409 The metal is very sharp at the ends so it cuts the enamal wireing making a short, its not heavyduty insulation.
The motor could work if you got lucky while laying the coil and didnt scratch any insulation, but the vibration from running ac through a coil rubs enough enamel of to short the coil
Yeah that was surprising,I almost think he did it on purpose to show is that important step because this obviously isnt his first motor rewind! Either way it was awesome he included that, if it was truly a mistake I think most guys would have edited that out and not mentioned it!
@@Troyvidihoo I completely agree.
ما سر علاقة المغناطيس بالكهرباء
Gear Show is the real deal. He's the only person in the TH-cam restoration game who actually rebuilds motors and fabricates battery packs.
Also, I went out and bought a Makita 7.2v cordless impact screwdriver after seeing you use it so frequently.
I get more confident after seeing your comment, thank you for the comment.
Please keep it up! Seriously great stuff!
check out 'my mechanics'
Have to say I was surprised and pleased to see you rebuild the armature, never seen anyone do that.
its prob because min wage where u're from is way over 50cts/hr...theres a whole industry of workers who rebuild armature n other consumable parts for a living, just nt in your part of the world.
You see it a lot in places like India, something we'd just throw away and get a new one, they strip and rebuild, rewinding isn't hard it's just time consuming and fiddly.
I once got a quote to have a 3 phase electromagnet rewound, the company wanted £700 to do it, a new one was £250.
@@aquakey9834 Not necessarily. I worked for a company in Germany which specialized in rewinding industrial motors for automated factories and heavy duty mining equipment. If you just need a standard 3p Motor its usually not worth the time, but old and specialized motors/generators are still beeing used all over different industries.
@@aquakey9834 ppppp
@@Mmouse_ g
Mad respect for you winding that copper!! You’re awesome.
Thank you!
That came out looking great!. The no load rpm is influenced by the strength of the permanent magnets. A stronger magnet results in more back emf and slower motor speed for a given input voltage. You could use 2 batteries in series. The original on off switch was designed for AC. You can protect it with a flyback diode for DC use. Well Done!
The switch it likely fine. The AC rating is typically higher than DC because most of the time it's not going to make contact at the peak of the sine wave. Without measuring the inductance of the coils, I can't determine the peak current of the the motor at start/stall. The battery probably has over current protection though.
A flyback diode as well as a 30ish volt zener diode would have been good though. Not to protect the switch, but the battery. The battery should have diodes protecting the MOSFETs, but not necessarily guaranteed. The switch does disconnect the battery from the motor so the back EMF won't be a problem until the battery decides it's dead and turns off. Then the switch would still be on and the motor connected to the battery and could send high voltage spikes back to the battery.
Using more turns of a thinner wire would have reduced the spindle speed and gave it more torque. I'm assuming that he did the math as number of turns at 100V and divided by 5 to get to what it could be at 20V.
Its really nice to see someone rewinding their motors. Dont let these old skills become rusty and forgotten
First thing I thought was "hmmm. No insulation paper. Well, he's the expert."
Well, great restoration as always!
I saw this armature has insulation inside, but the armature stack hole is narrow for new coil.
@@gear_show а почему на коллекторе не припаяны провода, почему не использовали щетки нужного формата, зачем оставили пружины в качестве токопрвода, пружины же быстро потеряют свои характеристики????
@@LISnonameI wondered the same. Why he did not solder the wires to the collector
These are the kind of things they need to teach in school. Amazing video, thank you sharing!
😅😅❤😅
哈哈，馬達那邊忘了包紙，白弄了！
又重拆掉，就是喜歡看有翻車的時候，讚！
Wow, My best friend, Thank you for your hard work in making the video. I enjoyed the good video. Have a happy day.
Thank you so much, my friend. I'm so glad you enjoyed this video.
Hes my best friend not yours.
What a challenge! I never saw someone modifying an AC motor into a DC motor. Well done!
Those motors are called universal motors, they natively run on both AC and DC. Most corded power tools have them. I've seen people build 120/240v DC power banks to supply power tools on remote sites, and they work just fine.
@@jzrgrmm ttjtjjtjtjjjjjtjtjutjjtjjtjt8pppjppp7p
@@jzrgrmm higl
So...!
You're the guy that showed me what's wrong with my JBL Xtreme...
My battery had a swollen module... so I discarded the whole battery... I'm using the speaker without the battery because it's always staying in one place...
👍 Keep up the work !!!
The brushes had braided copper wires going to them for a reason. A very good reason, especially at a low voltage / high current.
I recently was given a Makita impact driver. It's in a bad shape, no battery or charger. Can't find the courage to restore it. Hope I will manage it. Love your job. Great, relaxing & educational. Thanks from Greece🇬🇷🇬🇷🇬🇷. Keep up 👍👍👍
Da .mucha ayuda y efectiva graçias
Around 5000rpm that wasn't too bad it still enough for grind and very safety because the speed was't too big
Keep it up i love your video
Yes I will, thank you for the feedback!
I can't believe so much work, so complex, so skilful and finally it's working. For me it's art. Congratulations :)
0:45 *motor is sparking like crazy and sounds like literal explosions*
"It does not work well"
I laughed pretty hard.
Thank for this video, i asked you to do this modification in old angel grainder video by rewinding the armture and finally i see this video, it's very satisfying work👍
No noise, no lot of vibration, good grip and weigh balancing👌
I was excited for every minute in this video 😁
Keep going... 👏
Yes, I remembered you ask me to do it. Anyway, I'm so glad you like it, thank you!
This is the best made angle grinder i've ever seen. SO strong simple and servicable. Love the fact you can use a wrench on the hub.
It is spinning the wrong direction, it goes half the rated speed AND the battery will overheat / be destroyed due to no BMS.
@@swedishpsychopath8795 to be clear i was talking about how it was built originally, but i like the fact that the man rewound the motor instead of replacing it, it's cool and creative and solid. Also, my AC enihell grinder spins twice as fast as the same model and disc size but battery powered. He should add a bms tho.
@@swedishpsychopath8795 most batteries havs bms built in the pack, not sure about these chinese ones, but probably.
i have a bin full of starter motors, but i thought the duty cycle was so low using in a tool wasnt worth the effort.
Patrzenie jak przerabiasz i dajesz drugie życie elektronarzędziom, to przyjemność. Szkoda że ja tego nie potrafię. Dobra robota jak zwykle. Brawo Ty 😎
Jestem bardzo zmotywowany po przeczytaniu twojego komentarza, bardzo dziękuję!
@@gear_show uhdsjej
A very elegant solution. The weight of the batteries counterbalances some of the weight of the grinder.
Absolutely right, I feel it is easy to use, even it weighs 4 kg. Thank you very much!
You are very creative with a lot of skill, probably more than an industrial designer who has studied.
Wow, I'm so motivated after read your comment. Thank you so much!
Дружище ,👍..
Все твои видио смотрю..
Браво...Ты по ходу уже все перечинил и уже не знаешь что переделать..,😉...Браво так держать.
Да я сделаю. Я рада, что вам понравилось это видео, большое спасибо😉!
Great work. I am a DIY enthusiast and seeing your work and the ideas you implemented when you face any problem. Gives me inspiration. Keep it up good sir.
i love this guy,he dosent fuck around ,just fixes it
Good save of an old grinder makes a fantastic modern retro tool not to shabby at all 👍
Maravillosa restauración maestro 👍
Молодец! Супер мастер! С удовольствием смотрю твои видео без перемотки ! Мозг и руки золотые! Спасибо за твои ролики, Большого успеха тебе во всем!
он убил рабочую ушм, сделав из неё уродца! что в этом видео хорошего???
@@user-gn6uc8pi7k рабочую?
@@user-gn6uc8pi7k У нее якорь закорочен был, а учитывая год выпуска и марку, сделал приличный хендмейт ради интереса. Так что самоделка ни разу не хуйня.
@@DoCRabbittttt ротор и статор перематываются. а это просто уродства винтажной вещи. было бы лучше если бы он распечатал собственный корпус, это был бы хэндмейд.
@@user-gn6uc8pi7k У неё корпус металлический и она в любой момент может начать хуярить током, если использовать от сети. Кто пользовался советскими дрелями - тот знает, как это "весело". Так что нормально переделал, вопрос только к снизившимся оборотам.
Brilliant restoration, especially rewiring the rotor twise.
Great job on the grinder,looks an sounds amazing,thanks for this videos sir.👍👍
Impeccable work, congratulations !!!! 👍🏻👍🏻👍🏻👍🏻🔝
2 words!! Simply awesome
Great build brother God bless you and keep the good work going 👍👍👌👌
that high amp current melting soldering wires and thin wires have put smile on my face
My man is over here hand winding the armature. What an absolute mad lad!
Excellent work! Seems to be well balanced and the weight of 4Kg is still light!
Thank you very much! It is lighter than my previous drill (5 kg).
Parabéns pelo seu trabalho muito bom continue assim ótimas ferramentas japonesas abraço aqui do Brasil 👍🏻🇧🇷
Muito obrigado! Estou tão feliz que o vídeo pop-up no feed do Brasil.
I knew this wasn't going to be a straightforward restoration, that you were up to something.. Well very nice 👌 work, thx for taking us along.. Take care my friend...
Thank you so much! I'm glad you like it.
Simply Outstanding Restoration work.
Parabéns seus vídeos são os melhores, eu estava esperando faz tempo por esse vídeo.
Muito obrigado! Estou tão feliz que você gosta deste vídeo.
That was a daring attempt and a successful one as well. At first I thought you're going to replace the armature with a RS-775 motor or a higher rated DC motor. The motor you converted I think its torque and RPM is equivalent to a heavy duty motorbike starter motor.
It's a great accomplishment surrounded with perfection.
Greetings from India.
By the amount it seemed to bog down when cutting I think it's 500-600w. Very cool but a bit slow.
Thank you ! pedagogic video. Recently i have do this, it cost me lot of time and money, more than simply buying a 20 V grinder.
You are a patient patient man and good job!!! Thank you for sharing
Excelente trabalho GearShow! Gratidão
Muito obrigado!
Muito bom parabéns..
Gerçek bir işcilik ve ustalık... Tebrikler...
Very satisfaction to watch...Great work dude, converting from electric to battery operated grinder
Você sim é um profissional 👍
Lo que pocos se dieron cuenta que que no tiene fuera, al desvastar no ubiera quedado al rojo vivo el tornillo y eso no debería de suceder lo mismo con el disco de corte se calentó la varilla por que no tiene nada de fuerza y corta muy lento lo que quiere de cir que no asentaba el disco y eso daba tiempo al calentamiento fuera de eso buen trabajo pero inservible
Great job. Your work is so neat and beautifully crafted. Thank you
Thank you so much!
so refreshing. why did this ease the tension in my muscles?! is this some new form of meditation!?
That's a nice idea, the weight distribution can be in the midle of the grinder
Thank you!
Bom trabalho, adaptação muito bem feita 👏👏
Muito obrigado!
Hi there you're videos are very good and one thing you should not check the leakeage current using line tester because line tester cant detect voltage bellow 80v better you use Multimeter...work safely...Electricity is very dangerous and life is very important...
Absolutely right, thank you so much for the tip.
One of your best restoration ever. That is just..... Brilliant...
Thank you very much!
This was very injoy able to watch. Not just your typical restoration.
Brilliant work done. Really interesting video.
Muy buen trabajo, felicitaciones ! Has medido la corriente sobre los 19 volts ?
I'm happy every time I see your new video, so I know a lot about unique and rare powertools that I don't find in my country.. great job.. greetings from Indonesian craftsmen.. 👍👍👍
Thank you so much! I'm glade it makes you happy.
@@gear_show Your Wellcome brother, 🙏I have the same interests and hobbies as you. but unfortunately in my country, maybe I will have difficulty getting certain parts if I want to restore powertools.. i'll wait for next video.. 👍
Gear show you are very hardworking and honest
Thank you again!
Очень впечатляет Ваша работа! Продолжайте в том же духе!
Чё тебя впечатляет? Как человек из старой болгарки сделал мусор?
@@user-qk7fn2rz9f изначально было 9.000 оборотов. Когла сделал то стало 4,700 оборотов. Ну да слабоватенько
@@user-tu3yq8iz1s Согласен, оборотов маловато.
Но, с небольшой доработкой ее можно использовать как полировальную машину - для этого оборотов как раз хватает.
Great job, always inspired by you, thank you
Thank you! I'm glad to hear that.
That was awesome. Thank you for the educational bits.
great video man :) as my grandfather used to say, we learn while we live :)
Great video. Love your skills. Unfortunately, it seems too slow for what we use. Just takes way too long to cut that little bolt, much less an 8-inch pipe.
Очень интересно, очень умело. Спасибо за вашу работу и ваши ролики!)
Пожалуйста, большое спасибо за просмотр!
Beautiful Restoration .
Good job dear friend ❤
Thank you for another wonderful video maestro.
Some feedback - it would be good if you put more subtitles in, like why you appeared to "quench" that heated bolt in oil.
Thank you!
The copper reweaving was near orgasmic so so amazing to see
Nice work and great skill. You need to rebalance the rotor after rewiring. In time the bearings will fail because of that.
Love your work greetings from Poland.👍 Keep recording.
Yes, I will do. Thank you so much! I'm glad you love my work.
This is amazing. I've never messed with winding wires but now I might try.
Good luck man.
It wont be easy, but if you find one with damaged windings its worth to shot, just need to figure out right thickness and number of windings. I would not use this as a gospel, make your own research to make sure you know what you are doing. Personally i would have just replaced bearings that were blown while rest was in good condition.
inpresionante explendido exelente magnifico fenomenal 👏👏👍
amazing modification of AC to DC grinder.
this guy have all proper, perfect, right tools, i like it.
정말 기술 좋네요.
AC모터를 DC모터로 바꾸는게 핵심 이네요....
Diagram at 10:26 showing the Armature, Commutator, Carbon Brush, and Magnets.
Me: "Whoa, something just flew WAY over my head"
I try to make it easy to understand. Will you understand it?
@@gear_show Unfortunately no, I have no idea how motors work. But your video was extremely entertaining and thorough!
This is by far the best rebuild or refurbished should I say, and converted over to battery that is too cool
What a Crazy restoration! Awesome!
잘봤습니다, 나도 모터의 코일을 변경해 보고 싶습니다. 좀더 힘이 커지게 코일을 변경 하고 싶은데, 쉽지가 않네요.gear show!, ! 대단 합니다. Good job 🤗🤭🥰🥰👍👍👍
네, 쉽지는 않지만 우리는 할 수 있습니다. 고맙습니다!
Muy bueno
Su trabajo de aprender bendiciones
That motor winding seemed a lot less bad than I would have thought but that was a lot thicker wire than what was there before
Excellent work 👍👍👍 . Thank you for sharing. Take care of yourself, be safe 🇨🇦
You're welcome and thank you so much, you too.
золотые руки у вас, хорошо получилось
Nice work and nicely done 👍
很棒的改造流程器動輸轉機!
IT'S A PLEASURE TO WATCH THE RESTORATION OF INSTRUMENTS
I'm glad it makes you happy.
Overwhelming amount of knowledge.
Перематывал мелкие моторы, но не якоря. Спасибо за подсказку!
a gracious bow to your skills, sir.
You did a fine job there Fella 👍
Привет коллега ремонт класс здоровья тебе и твоим близким я подписан на твой канал поставил лайк больше ремонтов коллега
Awesome restoration. I cried at 12:40😭
kerja bagus, saya suka dengan kreatifitas anda dan sangat menginspirasi saya, terimakasih doa terbaik untuk anda.
یکی از حسن خوب شما این است که شما از موسیقی استفاده نکردید وانسان خوب درک می کند که دارید چیکار میکنید من به شما تبریک میگم از این مهارت بسیار خوب شما
Ôi Anh Trai giỏi quá 👍
Cảm ơn Anh rất nhiều. Chúc Anh và gia đình mạnh khỏe ❤❤🌷
Not sure if I've seen other conversions like this. Low RPM and all the torque you need. Very nice.
Remarkable engineering wow well done.
Люблю смотреть ваши видео. Хотел бы стать вашим учеником. Так классно у вас всё получается. приятно смотреть.
Я мало что знаю об этом, это просто мое исследование и тестирование. Я так рада, что тебе это нравится.
Напрасно вы говорите что это просто. Я же вижу какой у вас профессиональный инструмент. Вы как Хирург, который делает сложные операции.
Thanks for sharing. God bless you 🙏
Same to you!