Saved me from buying a new Dremel. I laughed for 5 minutes at the title of the video. I dropped mine when it was fairly new years ago. I put up with the vibration ever since. I just received a new armature and brushes today. Couldn't figure out the blue wire. With your help, I got it all back together. Runs like it was new (before being dropped.) I very much appreciated the resolution and clarity of the video. Being able to see the tiny parts is awesome. THANK YOU!
Thanks so much Dave, you saved me just 47 euros. My 4000 faltered when I was cutting dry wall on the ceiling. I thought it was due the dry plaster dust that moving parts were clogged. I opened it withou any DIY video's and I cleaned everything. But I couldn't get the two big brackets tight to each other again. The drewel after cleaning still had the same symptoms. The brushes by the way were looking good. I decided to check Amazon and other DIY stores and found one 3000 for 47 euros. Then I checked youtube just as a last resort and found your video. After that, I rearranged the red wire which was blocking and clamping the big blue on/off piece. I could now easily close it again. At first the drewel was still a bit coughing. I left it running at 30000 for a minute and now it is functioning smoothly through all rpm's. When I tilt the drewel when running at higher rpm it starts hampering a little bit, but I claim that to be the gyroprecession effects.
You, mister, are a lifesaver. I stupidly took the Dremel apart, got everything mixed up and thought I'd need a new one. And then I put it back together with the aid of this video. Works perfectly, and even the bothersome screeching sound is gone now! Thank you!
+Susanna Kaske Thank you for the kind words. Folks like you (and me) are the reason that I was motivated to make the video. Knowledge is only power when it is shared.
Well done video. Great focus, framing, timing, length. Good explanation of the parts and pathways. The "resistor", metal can with the tapered plastic, is a "thermal fuse". They look like a few of the diode packages. When I worked at the electronics parts store, NOT Radio Shack, NTE (RCA/Philips/TCG) sells them for less than 20 cents each. Mine says 216C plus other things. That is a 216 Celsius thermal fuse. The same size device can be found wrapped in fiberglass insulation tubing buried within in most motors, coffee pots, toasters, etc. It may be tested just like any other fuse. ohm meter. beep = good. no beep = bad. They are crimp only. Soldering will melt the wax inside and ruin a brand new one. (Don't ask me how I know. lol. 3 tries later. The plastic bag they come in, comes with two brass crimps. Now I know why. lol.) They can handle huge amounts of current and voltage. Half a degree above the rating and poof, dead. I am not trying to be a know-it-all. Got an AA in Electronics. I'm like you. Love to take stuff apart and see which part I let the smoke out of.
I also done a dirty job. Done some artwork on a piece of slate. Then I cleaned the Dremel tool with an air matress blower . I think it blew the clip off. Grateful for guys like you Dremel tool pioneers.
Thank you SO MUCH for this video. My Dremel has been slowly losing power. I had just changed out the brushes but it sounded like they needed replaced again. When I opened up one side to look, the brush had been dragged into the motor and obliterated and the blue wire was out of place. I'm not sure if that's why the brush got sucked in, but if you hadn't posted this video, I would've never figured out where it went. I even looked on ereplacement parts for a tutorial and there wasn't anything explaining the wiring. You rock, thank you!
I don't usually take the time to comment, but you saved me a lot of frustration. I was in the middle of a job when I powered off my two year old Dremel. I came back to it and attempted to power it back on, but it was a DB as my grandfather would say, a Dead Body. I knew what it wasn't, but held off until I found a video before opening up this spring loaded contraption. Lo & behold, I opened it carefully and "upside down" and wouldn't you know my blue wire wasn't attached at all. Upon reassembly (thank you for the tips about guiding the various wires), she works and I can now stop cursing the name Dremel. Thank you once again for sharing your knowledge and being an asset to the TH-cam community as well as those into DIY.
Hi Dave, Excellent video and much appreciated. Due to one reason or another, the threaded shaft of my Dremel become burred and I was unable to screw on the collet nut. I was disappointed to find that this threaded shaft is part of the armature unit and has to be replaced as a whole unit. I was able to purchase a replacement part but was apprehensive about replacing it. After finding and watching your video, I am far more confident and informed now to handle the task. As you state, knowledge is power when it is shared and I truly am thankful you shared your knowledge in such a clear and informative way. Well done and Thanks again.
I think this is the most informative video I’ve ever watched. Your delivery is absolutely on point and when you are that thorough and having the demeanor you have, people that have a harder time learning something like this can retain it better. Great job 👏🏼👏🏼👏🏼 subscribed.
Hi, THANKS A LOT. I happened to do very a dusty job ( taking out some hard set tile grout). That made the slide power switch got a bit stiff. So google - TH-cam and I land on this. First thanks for this. Short sweet and to the point. My Dremel 4000 ( European version) doesn't have the coil brushes installed the same way. You can't unscrew them. So all you do is take out the screws that hold the dremel halves together and pull the tops side( side from where the 5 holding screws are fitted) out. You have to be careful as the spring loaded plastic brush caps can fly out. I suppose ( in hindsight) you can put two fingers on them while you gently prise out the top half. Your video gave me the courage to pull my Dremel 4002 apart. Knowledge is power and sharing it empowers others. ..
I know this video is old but today my dremel quit working and i took it apart and cleaned it all up then put back together and it ran like garbage, lo and behold that blue wire got me i really appreciate your video it was most helpful
THANK YOU!!!!!!!!!! This is just what I needed! I had wired it incorrectly. The little brass boxes on either side are where the carbon brushes sit. Figuring out how they plugged back in is the guts of disassembly. So glad you showed us how with clear visuals. So very helpful, very grateful!
Thank you for the great macro shots from above. It really helped with re-assembly and getting the wires routed the way they are suppose to be. Mine had a seized front bearing, which I was able to fix by removing its dust seal, blowing it out with compressed air, and re-lubricating. But it didn't run after re-assembly. Turned out the black coil wire connector had slipped loose, and it still looked connected! Others have reported that one tends to be loose from the factory. All is well now. Very helpful video.
Thanks so much. I hit my glove with the dremel and it got wrapped up. It wouldn’t turn on after that. I took it apart and was able to tell the switch didn’t look right because of your clear video. Works like a charm now woohoo!
This video is spot on. Very knowledgeable, thorough, and breaks down every critical step, which reduces repair time, guesswork and frustration. Mine just took a shit one day seemingly at random, which was particularly disappointing because it was probably the 6th time I'd used it in the three weeks I had owned it. Apparently this little blue bastard became dislodged during use or a maybe I dropped it and don't remember. With the aid of this video i was able to tear it down, seat the wire, and lubricate and fine tune my Dremel 4000. Thank you for the very helpful video TXW5CSM.
I've worked on my dremel 395 before...but the 'Blue Wire' on the 4000 had me stumped! Thank you so much for making this video. The video quality is the best I've seen on TH-cam. Your video was a life saver (or at least $149.00). :-)
I had one of these apart after cleaning - and ended up not putting it back together for circa 1 year. This video was rather useful. Thanks & 73's de M0WUL.
I had to clean my dremel, cause the power button got stuck from dust. I took the whole thing apart and couldnt get it back together and tried for probably an hour. The first two things you said after opening it were the Problem... Thank you so much, its working again now, and i know now how to do it!
Awesome video. Thanks for posting. I only wish I checked Google/TH-cam before I wasted a good hour trying to figure it out. I left my 4000 outside, it rained, then wouldn't work. I made the mistake of not keeping Dremel side down when taking it apart, so guts stayed in the wrong half, pulling off both the red and blue wires. Don't bother calling the 800 number. Technician was useless. No, there wasn't a wiring diagram available, no there wasn't a colored picture of the internals, no she wouldn't tell me where that pesky blue wire went (I can't be the first person asking about it! But she did say something about liability... yeah, some product support! Was tempted to buy another, open it up, then return it... Anyway, back to figuring it out myself.) From bends in red wire, found the stator connection on the other side. And finally, from the blue bends, I saw that little depression under the brush. Your video was good to confirm that was the right place. Bad news was that I've lost speed control. Full speed only. So I guess after all this, I need a new board or whole new tool! Moral of the story... Don't get your Dremel tool wet! But again, video was very well done. Cleaning out the tool along with new brushes should extend the life, rather than just pitching it which I'm afraid most people will do.
Dude! I stared at that blue wire for 20 minutes until I thought, "Surely I'm not the first person to wonder where that thing came from". First search result... mysterious blue wire. Thanks man!
Thank you so much for your kind thought of posting this video. I too found I could not fathom where this connector joined to, so you deserve a hearty thanks, and for your superbly clear instruction. Best wishes!
I really appreciate this video! My blue wire clip wasn't in the place it should be, so the tool quit working after a few hours. When I opened the case, the blue wire was just there, not attached to anything.
A thousand thanks to you ! I've been searching where that blue wire needed to go for days after changing the speed variator of my dremel.I'm just putting a few french words here in hope that it will help Google bring people who have the same issue here."fil bleu du variateur électronique de la dremel 4000, composant F013400046"
Haha ……. I was flummoxed as to how that wire attached to the brush casing and then I came across this fantastic tutorial ….. indeed sharing knowledge is a beautiful present 🙏 thank you very much
The title of your video couldn't have been any better! Thanks so much for sharing and saving me at least an hour today trying to put that Dremel back together!!!
Excellent video. Thank you so much for showing us where that elusive little blue wire goes. Now, I have more questions, like, how did it break free of its home in the first place? Crazy. It's so pinned in there you can't imagine it coming out of there. Thank you, again. Great video.
Hello, As it was over 9 years ago, I must assume that this issue was eventually noticed by Dremel and that the seating of the wire into the recess was made a bit more positive. That is my best guess. Mine did not require ANY force to remove it or I would have noted the location and taken a photo prior to disassembly. I hope this helps. Thanks for watching!!
Thank you so much for your time and patience in locating where the BLUE WIRE is supposed to go. I had a dickens of a time trying to figure that one out! I have a call into Dremel for the fix and now I can cancel that.
Now, in dec 19, I had the same problem after cleaning my Dremel: this mysterious blue wire and its odd end with no place to plug it. I came to TH-cam and saw your video with this original and right title! Tks a lot, too and if you come to Sao Paulo I´ll buy you some Caipirinhas for these beautiful and on time help!
Absolute hero. Cheers mate. Mine filled with tile dust so giving it a good clean out. Random blue wire panic over. Great vid with the zooming in and all 👍
Thanks for solving the mistery for me! In my case it still does not work though, it only starts when I hit it pretty hard near the brush on the opposite side of the speet potentiometer. Once started it runs. I tried to “kick start” it thinking it was a brush contact issue but no difference. I’ll keep diagnosing I guess! Thanks for the mystery solving!
When I disassembled the damned thing for first time I was about to throw it away in garbage. I thought there’s no way to put it back together... Then I saw the video and it’s up and working again. Thanks for sharing!!!!!
Blue wire is a feedback to the microcontroller .it has the functional role of keeping speed constant in rapport to the load at the shaft. On the brush you wil get an pulse at evey pass trough the rotor coils. This pulses are larger at low speed (les pulses per second) and when this happens at the same voltage given by the speed potentiometer witch is converted into voltage trough ADC from uC this pulse pin tell to the processor to increase the power at the triac. I hope I am clear enough and sorry for too deep details into controller board because this video is just for repair not development of better controller
Ovidiu, Thanks so much for explaining the technical need for the blue wire. I am sure that your in depth explanation is very valuable to those who have this question and search for this video.
The function of the mysterious blue wire was bothering me for quite some time, as it came off during disassembly by itself with no way of knowing where the end was attached to came. Thank you @TXW5CSM and @Ovidiu Ovidiu so much for your explanation.
just a quick tip... take pictures whit your phone while you take stuff apart so you know where stuff goes when its time to put it back together. that would save you the 45 min it took to find the solution. it might seam a bit dumb but working whit computers this has saved me a loot of time.
Whenever you take something apart take your time and take lots of photos from different angles. Also lay things out in the order you remove them and use a magnetic whiteboard for screws that way you can label them too.
This was exactly the problem I ran into with my Dremel, fixed the problem with the blue wire today thanks to you, fantastic and thanks a lot for this inspiring video!
I was just watching this to learn how to disassemble my dremel and then I seen this blue wire and I was like wtf? And then I remembered the videos title lol. Nice work man!
Thank you thank you thank you. I’ve been sat here for at least a hour looking for where this dam blue wire goes to. I really had no idea so I thought TH-cam ! I probably would of still been here tomorrow looking for this and in the end I’d of just used it for spares and bought another ohh and that’s another thing don’t shot your old dremel away because you can use it for spares and repairs. The wiring was a little different in my dremel to the one shown even though it’s the same model. Must be down to the 240v system we have in the UK. I found a 0.3 mm drill bit inside the dremel and the rear bearing is rattling so it time I got a new one I think as the bearing is shot. Have no idea how the drill bit got in there though. It may be down to little fingers I think.
Thank you! I opened mine apart and couldn't figure out where to put the blue wire. Turned out that still wasn't the problem. Some how one of the tabs on the housings for the brushes got bent. Bent it back into place and works like a charm now.
Thank you a lot man. Your video was very helpful for fixing my dremel. It was damaged when doing a cut on a bearing ring. A Little piece of plastic of the stator was broken, so I took all out, and found then difficult to re-assemble it again. So thanks again.
That thing with the carbon brush holder is not a resistor but is a thermal cut-off fuse. I had blown this fuse before and I replace it with a 80 degree Celsius fuse. You should not overheat the dremel or you will have the same problem just like me and will need to change the fuse.
I really can't believe they put a one shot non-resettable thermal fuse in the tool, I was shocked when I figured out why mine stopped working, it wasnt even that hot!. It seems to be a case of safety over common sense. Dremels lawyers probably demanded it from some idiot being burned with a previous model. I can only imagine how many people have blown that fuse and either said screw it and bought a new one or were turned off by Dremel and went to another brand. I just replaced the fuse with a short piece of solid #14 copper wire. Its been a few years and haven't had a problem. I figure I can let my nose be my fuse. I know that smoldering magnet wire smell very well, lots of experience! Lol!
Many thanks +Edward Ng, you just saved me the cost of a new tool. I did a continuity test on this thermal fuse and sure enough, it was blown. Jumped a #14 copper wire bypassing the fuse and it came back to life! I will replace the blown part soon, Dremel part number 2610009024 (comes as a complete set as a "Brush holder") These are hard to come by, compared to brush replacements.
Thank you so much sir! I had to shorten the power cable due to the individual wires sticking out of the cord, and after doing that, I was like "Where the hell did this blue wire come from?!'
Thank you very much for this video. I did grout work with my Dremel 4000 and wanted to take it apart to clean it and your video was perfect. Much appreciated Sir!
Dude! You are the coolest! Thank you so much for making this video! There was no other reason for you to make this other than to be of help. And indeed, helpful you have been. Thanks!
Thanks for a clear and well explained video. Though my Dremel is a different model, I still learned something from you. I have a later '400 Digital' model with an extra black wire (no blue like yours) and very different looking brushes. Just putting it out there - in case someone reads this comment - where does the spare black wire go? It has a slightly curved piece of copper on the end but there isn't any likely looking component it may attach to. I might do a question asking TH-cam video - does anyone do that?
Thanks Dave. You saved me from burning out the mother board. I did consider it may have been clipped onto the projecting diode as it appeared covered with a metallic coating. Again thanks
thanks my friend, I order a new electric switch for my Dremel 4000 and I intent to replace it by myself, I believe the info provided here will be a great help, when reassembling the Dremel.
Thanks mate, I'm from Mogi das Cruzes, São Paulo Brazil and I can tell you that I've not found any tutorial explaining this as his. Neither the Dremel itself. Congratulations and thank you for sharing your knowledge with us. Hugs! (Google translation)
Márcio, Muchas gracias por sus amables comentarios. Es muy agradable recibir una respuesta positiva sobre mis videos. Por favor comparta este y otros. Como digo, el conocimiento es sólo poder cuando se comparte!
Thank you men, you save my life, because i try to replace the thermal fuse and i accidentally move the position of the blue wire and in the moment to reemsamble i dont know where it was connect.
On another note, the brush assembly plugs aren't threaded in my 2019 euro version, gotta pop open the chassis to remove them... And the chassis still has threads for them. Not sure if it's a global development but somewhat irritating.
the 4000 has the function of keeping a steady rpm even when put under a load..looking at this blue wire and its location tells me its most likely the sensor wire for this rpm feature.being its place is right there with the brushes..where it can since rpm..
Obrigada pelo seu tutorial, estou começando a fazer Luminárias em PVC, é um trabalho muito bonito e artesanal, faço parte de alguns grupos no Facebook, temos muitos problemas com a Dremel vendida aqui no Brasil, para a troca do carvão (escova) temos que tirar toda a tampa, sem contar com o preço dos acessórios que é muito caro. Quando vi seu tutorial até compartilhei com o grupo, mesmo não sabendo falar inglês está muito nítido o que você está fazendo e sei que vai ajudar muitos amigos meus. Obrigada, obrigada, que Deus te abençoe.
Sra Santos, Muito obrigado pelas suas máveis palavras . Apraz-me que a barreira da língua não foi um problema . Tenho o prazer de ajudar os outros. Saudações do Texas . Deus Abençoe!
+Vanda A. Santos Realmente aqui no Brasil ficou ruim esse sistema de troca de escovas. Meu Dremel antigo era semelhante a este do nosso amigo estrangeiro, e você pode reparar que onde vai aquela tampinha preta da escova nos nossos aparelhos, tem uma rosca na carcaça. Basta descobrir onde comprar as tampinhas de rosquear! Vou tentar, se tiver notícias posto aqui :)
+Gabriel Tessari A minha Dremel é a 4000, vi a tampa mas não quero me arriscar a tirar (por enquanto) e nova ainda. Se descobri alguma coisa será uma boa, quanto mais informações melhor, vou aguardar e desde já agradeço. Até +
+Vanda A. Santos Descobri que o código da tampinha que precisamos é 2 610 006 518, e só é utilizada na Dremel dos Estados Unidos e da Inglaterra. O problema é conseguir a pecinha no Brasil, não consigo nem o porta-escova da minha que queimou o termo fusível de proteção...vou ter que comprar um termo fusível e trocar eu mesmo.
I e baught 3 dremels in the last 2 1/2 years. Now none work with only a few hours on each. Myt last is a 4000. Just like the other two . I was using it, turned it off. Go to use it a few minutes later and nothing. I took it apart and dont see nothing. If it's not to much to ask, any tip are suggestions.
Its 2019 now, 5 years after you made this it helped me a lot! I was indeed getting crazy about the blue wire :-), My tool is working again thx a lot, if you ever come to Belgium I buy you some beers or other drinks!
Thanks for this, just what I needed, my tool got a tad wet and cut out, took apart to dry out and yes that wire could not work out where it went until I saw this, thanks.
Love the saying and love the video. I would have enjoyed the section on operation. Im sure someone familiar with the Dremmel would be bored but for those of us who dont know squat. We should be like a sponge to water, Keep Trucking..
Awesome! Thank You! I thought it went there.. After I failed soldering it to the black wire. Hope I didn't F things up. We'll see.. Thanks for solving the blue wire mystery...
Hi TX, awesome video! I live in Brazil and I plugged my dremel 4000 in a 220w jack... Can you please tell me what are the possible consequences and if it's to hard fixing. Greetings and many tanks ;)
You've likely allowed the magic smoke to be released from many components. Others may have more technical detail but you may just want to buy a new one. Glad you liked the video.
Following these steps didn't get her working again, but was a very methodical, detailed and practical vid. Very happy I watched and read the comments because Ed Ng's comment will be my next step in trying to un-shit my Dremmel. It died drilling a piece of fucking cedar!!!
The blue wire is not a feedback to the microcontroller as stated below in the comments section. Microcontrollers with feedback circuitry are used in DC BRUSHLESS motors to sense direction of rotation and speed. The type of motor in your Dremel 4000 is an old school universal motor (been around for a century). This motor can work on DC or AC hence the name universal. In its application in the Dremel tool it receives a pulsed DC input from the controller. The blue wire is simply the neutral return to the speed control board. This is also old school (it's a pulse width modulator to control average voltage/speed to the motor). There are a number of complaints on the internet about these Dremel motors arcing/running rough/ and buzzing. An educated guess from someone with an electrical engineering background.. I think this is due to this blue wire's friction-only contact with the brush holder which under vibration could cause arcing and rough running. This would only get worse as the tool gets older with use. On the current models sold in Australia (in 2017) they have done away with the removable brush caps (so the brushes are no longer serviceable). The tool I bought today is running rough from new with an arcing sound at all speeds - very noticeable at speed 17 on the controller potentimeter. This happens to coincide with harmonic balance vibration at this speed. Since it is faulty from new I'll be returning it tomorrow for refund. When Dremel bring out a brushless version I might be interested again.
Thank you for this video. There is a part missing off of my dremel and I had no idea what to look for. Hopefully I can find it now that I know it's a brush cap and and know what to look for. Thank you again. :)
Saved me from buying a new Dremel. I laughed for 5 minutes at the title of the video. I dropped mine when it was fairly new years ago. I put up with the vibration ever since. I just received a new armature and brushes today. Couldn't figure out the blue wire. With your help, I got it all back together. Runs like it was new (before being dropped.) I very much appreciated the resolution and clarity of the video. Being able to see the tiny parts is awesome. THANK YOU!
Thanks so much Dave, you saved me just 47 euros. My 4000 faltered when I was cutting dry wall on the ceiling. I thought it was due the dry plaster dust that moving parts were clogged. I opened it withou any DIY video's and I cleaned everything. But I couldn't get the two big brackets tight to each other again. The drewel after cleaning still had the same symptoms. The brushes by the way were looking good. I decided to check Amazon and other DIY stores and found one 3000 for 47 euros. Then I checked youtube just as a last resort and found your video. After that, I rearranged the red wire which was blocking and clamping the big blue on/off piece. I could now easily close it again. At first the drewel was still a bit coughing. I left it running at 30000 for a minute and now it is functioning smoothly through all rpm's. When I tilt the drewel when running at higher rpm it starts hampering a little bit, but I claim that to be the gyroprecession effects.
You, mister, are a lifesaver. I stupidly took the Dremel apart, got everything mixed up and thought I'd need a new one. And then I put it back together with the aid of this video. Works perfectly, and even the bothersome screeching sound is gone now! Thank you!
+Susanna Kaske
Thank you for the kind words. Folks like you (and me) are the reason that I was motivated to make the video. Knowledge is only power when it is shared.
Well done video. Great focus, framing, timing, length. Good explanation of the parts and pathways.
The "resistor", metal can with the tapered plastic, is a "thermal fuse". They look like a few of the diode packages. When I worked at the electronics parts store, NOT Radio Shack, NTE (RCA/Philips/TCG) sells them for less than 20 cents each. Mine says 216C plus other things. That is a 216 Celsius thermal fuse. The same size device can be found wrapped in fiberglass insulation tubing buried within in most motors, coffee pots, toasters, etc. It may be tested just like any other fuse. ohm meter. beep = good. no beep = bad. They are crimp only. Soldering will melt the wax inside and ruin a brand new one. (Don't ask me how I know. lol. 3 tries later. The plastic bag they come in, comes with two brass crimps. Now I know why. lol.) They can handle huge amounts of current and voltage. Half a degree above the rating and poof, dead.
I am not trying to be a know-it-all. Got an AA in Electronics. I'm like you. Love to take stuff apart and see which part I let the smoke out of.
I also done a dirty job. Done some artwork on a piece of slate. Then I cleaned the Dremel tool with an air matress blower . I think it blew the clip off. Grateful for guys like you Dremel tool pioneers.
Thank you SO MUCH for this video. My Dremel has been slowly losing power. I had just changed out the brushes but it sounded like they needed replaced again. When I opened up one side to look, the brush had been dragged into the motor and obliterated and the blue wire was out of place. I'm not sure if that's why the brush got sucked in, but if you hadn't posted this video, I would've never figured out where it went. I even looked on ereplacement parts for a tutorial and there wasn't anything explaining the wiring. You rock, thank you!
I don't usually take the time to comment, but you saved me a lot of frustration. I was in the middle of a job when I powered off my two year old Dremel. I came back to it and attempted to power it back on, but it was a DB as my grandfather would say, a Dead Body. I knew what it wasn't, but held off until I found a video before opening up this spring loaded contraption. Lo & behold, I opened it carefully and "upside down" and wouldn't you know my blue wire wasn't attached at all. Upon reassembly (thank you for the tips about guiding the various wires), she works and I can now stop cursing the name Dremel.
Thank you once again for sharing your knowledge and being an asset to the TH-cam community as well as those into DIY.
Hi Dave, Excellent video and much appreciated. Due to one reason or another, the threaded shaft of my Dremel become burred and I was unable to screw on the collet nut. I was disappointed to find that this threaded shaft is part of the armature unit and has to be replaced as a whole unit. I was able to purchase a replacement part but was apprehensive about replacing it. After finding and watching your video, I am far more confident and informed now to handle the task. As you state, knowledge is power when it is shared and I truly am thankful you shared your knowledge in such a clear and informative way. Well done and Thanks again.
I know this is 6 years old and you probably don’t read the comments anymore but you just saved the day! Thanks so much!
It's always good to know that a video helps someone. That's why I did it.
I think this is the most informative video I’ve ever watched. Your delivery is absolutely on point and when you are that thorough and having the demeanor you have, people that have a harder time learning something like this can retain it better. Great job 👏🏼👏🏼👏🏼 subscribed.
I am very pleased that this video helped you. Thank you for the praise and the subscription.
Hi,
THANKS A LOT. I happened to do very a dusty job ( taking out some hard set tile grout). That made the slide power switch got a bit stiff. So google - TH-cam and I land on this. First thanks for this. Short sweet and to the point. My Dremel 4000 ( European version) doesn't have the coil brushes installed the same way. You can't unscrew them. So all you do is take out the screws that hold the dremel halves together and pull the tops side( side from where the 5 holding screws are fitted) out. You have to be careful as the spring loaded plastic brush caps can fly out. I suppose ( in hindsight) you can put two fingers on them while you gently prise out the top half.
Your video gave me the courage to pull my Dremel 4002 apart. Knowledge is power and sharing it empowers others. ..
Thanks you bro!!! , an hour with the infamous blue cable loose and without knowing where to place it, you are the best !!
I know this video is old but today my dremel quit working and i took it apart and cleaned it all up then put back together and it ran like garbage, lo and behold that blue wire got me i really appreciate your video it was most helpful
THANK YOU!!!!!!!!!! This is just what I needed! I had wired it incorrectly.
The little brass boxes on either side are where the carbon brushes sit. Figuring out how they plugged back in is the guts of disassembly. So glad you showed us how with clear visuals. So very helpful, very grateful!
Thank you for the great macro shots from above. It really helped with re-assembly and getting the wires routed the way they are suppose to be. Mine had a seized front bearing, which I was able to fix by removing its dust seal, blowing it out with compressed air, and re-lubricating. But it didn't run after re-assembly. Turned out the black coil wire connector had slipped loose, and it still looked connected! Others have reported that one tends to be loose from the factory. All is well now. Very helpful video.
Thanks so much. I hit my glove with the dremel and it got wrapped up. It wouldn’t turn on after that. I took it apart and was able to tell the switch didn’t look right because of your clear video. Works like a charm now woohoo!
Came here for the same reason, you sir are a saint, thank you for taking the time to share the knowledge
This video is spot on. Very knowledgeable, thorough, and breaks down every critical step, which reduces repair time, guesswork and frustration. Mine just took a shit one day seemingly at random, which was particularly disappointing because it was probably the 6th time I'd used it in the three weeks I had owned it. Apparently this little blue bastard became dislodged during use or a maybe I dropped it and don't remember. With the aid of this video i was able to tear it down, seat the wire, and lubricate and fine tune my Dremel 4000. Thank you for the very helpful video TXW5CSM.
I've worked on my dremel 395 before...but the 'Blue Wire' on the 4000 had me stumped! Thank you so much for making this video. The video quality is the best I've seen on TH-cam. Your video was a life saver (or at least $149.00). :-)
I had one of these apart after cleaning - and ended up not putting it back together for circa 1 year. This video was rather useful. Thanks & 73's de M0WUL.
I had to clean my dremel, cause the power button got stuck from dust. I took the whole thing apart and couldnt get it back together and tried for probably an hour. The first two things you said after opening it were the Problem... Thank you so much, its working again now, and i know now how to do it!
Awesome video. Thanks for posting. I only wish I checked Google/TH-cam before I wasted a good hour trying to figure it out. I left my 4000 outside, it rained, then wouldn't work. I made the mistake of not keeping Dremel side down when taking it apart, so guts stayed in the wrong half, pulling off both the red and blue wires. Don't bother calling the 800 number. Technician was useless. No, there wasn't a wiring diagram available, no there wasn't a colored picture of the internals, no she wouldn't tell me where that pesky blue wire went (I can't be the first person asking about it! But she did say something about liability... yeah, some product support! Was tempted to buy another, open it up, then return it... Anyway, back to figuring it out myself.) From bends in red wire, found the stator connection on the other side. And finally, from the blue bends, I saw that little depression under the brush. Your video was good to confirm that was the right place. Bad news was that I've lost speed control. Full speed only. So I guess after all this, I need a new board or whole new tool! Moral of the story... Don't get your Dremel tool wet! But again, video was very well done. Cleaning out the tool along with new brushes should extend the life, rather than just pitching it which I'm afraid most people will do.
Dude! I stared at that blue wire for 20 minutes until I thought, "Surely I'm not the first person to wonder where that thing came from". First search result... mysterious blue wire. Thanks man!
peteandalie Same for me!
OMG same here
Yup... Blue wire mystery! And here I am...
same here : ))
Same but I set there over an hour before I tried TH-cam
Thank you for the video! You´ve just saved me 105 euros for new machine.
Thanks. This solved my problem. It also is one of the most detailed, clear, and well done instructional videos I have seen on TH-cam.
Thank you so much for your kind thought of posting this video. I too found I could not fathom where this connector joined to, so you deserve a hearty thanks, and for your superbly clear instruction. Best wishes!
I really appreciate this video! My blue wire clip wasn't in the place it should be, so the tool quit working after a few hours. When I opened the case, the blue wire was just there, not attached to anything.
Thanks i took it apart trying to see it the 110v can be adjusted to 220v no it cannot.. Anyway managed at least to put it working thanks to this video
A thousand thanks to you ! I've been searching where that blue wire needed to go for days after changing the speed variator of my dremel.I'm just putting a few french words here in hope that it will help Google bring people who have the same issue here."fil bleu du variateur électronique de la dremel 4000, composant F013400046"
Haha ……. I was flummoxed as to how that wire attached to the brush casing and then I came across this fantastic tutorial ….. indeed sharing knowledge is a beautiful present 🙏 thank you very much
The title of your video couldn't have been any better! Thanks so much for sharing and saving me at least an hour today trying to put that Dremel back together!!!
Excellent video. Thank you so much for showing us where that elusive little blue wire goes. Now, I have more questions, like, how did it break free of its home in the first place? Crazy. It's so pinned in there you can't imagine it coming out of there. Thank you, again. Great video.
Hello, As it was over 9 years ago, I must assume that this issue was eventually noticed by Dremel and that the seating of the wire into the recess was made a bit more positive. That is my best guess. Mine did not require ANY force to remove it or I would have noted the location and taken a photo prior to disassembly. I hope this helps. Thanks for watching!!
Thank you so much for your time and patience in locating where the BLUE WIRE is supposed to go. I had a dickens of a time trying to figure that one out! I have a call into Dremel for the fix and now I can cancel that.
Now, in dec 19, I had the same problem after cleaning my Dremel: this mysterious blue wire and its odd end with no place to plug it. I came to TH-cam and saw your video with this original and right title! Tks a lot, too and if you come to Sao Paulo I´ll buy you some Caipirinhas for these beautiful and on time help!
Absolute hero. Cheers mate. Mine filled with tile dust so giving it a good clean out. Random blue wire panic over. Great vid with the zooming in and all 👍
Many thanks. I could not figure out where the blue wire went. Excellent presentation.
THANK YOU for the wire close-up. I screwed mine up on reassembly and this was very, very useful.
Thanks for solving the mistery for me! In my case it still does not work though, it only starts when I hit it pretty hard near the brush on the opposite side of the speet potentiometer. Once started it runs. I tried to “kick start” it thinking it was a brush contact issue but no difference. I’ll keep diagnosing I guess! Thanks for the mystery solving!
Excellent video. You answered my "Blue Wire" question as well as the routing of the wires. Thank you very much for sharing your knowledge.
God bless you!!!
That blue wire was driving me nuts where did it hook to!!
It is so WONDERFUL to SHARE knowledge my friend!!
Thanks so much
When I disassembled the damned thing for first time I was about to throw it away in garbage. I thought there’s no way to put it back together... Then I saw the video and it’s up and working again. Thanks for sharing!!!!!
Blue wire is a feedback to the microcontroller .it has the functional role of keeping speed constant in rapport to the load at the shaft. On the brush you wil get an pulse at evey pass trough the rotor coils. This pulses are larger at low speed (les pulses per second) and when this happens at the same voltage given by the speed potentiometer witch is converted into voltage trough ADC from uC this pulse pin tell to the processor to increase the power at the triac.
I hope I am clear enough and sorry for too deep details into controller board because this video is just for repair not development of better controller
Ovidiu, Thanks so much for explaining the technical need for the blue wire. I am sure that your in depth explanation is very valuable to those who have this question and search for this video.
The function of the mysterious blue wire was bothering me for quite some time, as it came off during disassembly by itself with no way of knowing where the end was attached to came. Thank you @TXW5CSM and @Ovidiu Ovidiu so much for your explanation.
My Dremel 4000 is pulsing on and off any ideas is it related to blue wite
just a quick tip...
take pictures whit your phone while you take stuff apart so you know where stuff goes when its time to put it back together.
that would save you the 45 min it took to find the solution.
it might seam a bit dumb but working whit computers this has saved me a loot of time.
Whenever you take something apart take your time and take lots of photos from different angles. Also lay things out in the order you remove them and use a magnetic whiteboard for screws that way you can label them too.
That's a good tip! :)
+Commando Squeak never actually thought about using a whiteboard. great idea.
Man, try to open this one and take a picture of it's wires without ending watching this video ... The wire's not even attached to anything .
Thank you it would have taken me hours to figure out that blue wire.
Thanks for explaining this issue saved me a lot of heart ache.
Thanks to people like you i have learned more from you-tube than i ever did at school.
Mystery finally solved...
Thanks for the very neat and structured walk-through!
This was exactly the problem I ran into with my Dremel, fixed the problem with the blue wire today thanks to you, fantastic and thanks a lot for this inspiring video!
I was just watching this to learn how to disassemble my dremel and then I seen this blue wire and I was like wtf? And then I remembered the videos title lol. Nice work man!
lol, you had to watch a video to disassemble a dremel! lol fuckign beta!
It's all in the detail and you've got them ALL covered with this tutorial - thank you - my 4000 is back to brand new again.
Thank you thank you thank you. I’ve been sat here for at least a hour looking for where this dam blue wire goes to. I really had no idea so I thought TH-cam ! I probably would of still been here tomorrow looking for this and in the end I’d of just used it for spares and bought another ohh and that’s another thing don’t shot your old dremel away because you can use it for spares and repairs. The wiring was a little different in my dremel to the one shown even though it’s the same model. Must be down to the 240v system we have in the UK. I found a 0.3 mm drill bit inside the dremel and the rear bearing is rattling so it time I got a new one I think as the bearing is shot. Have no idea how the drill bit got in there though. It may be down to little fingers I think.
Thank you Dave. You are the man. Could not have done it without you.
Thank you! I opened mine apart and couldn't figure out where to put the blue wire. Turned out that still wasn't the problem. Some how one of the tabs on the housings for the brushes got bent. Bent it back into place and works like a charm now.
Thank you a lot man. Your video was very helpful for fixing my dremel. It was damaged when doing a cut on a bearing ring. A Little piece of plastic of the stator was broken, so I took all out, and found then difficult to re-assemble it again. So thanks again.
I thought I'd broke it until I found your video. Thanks for posting a really good clear explanation.
That thing with the carbon brush holder is not a resistor but is a thermal cut-off fuse. I had blown this fuse before and I replace it with a 80 degree Celsius fuse. You should not overheat the dremel or you will have the same problem just like me and will need to change the fuse.
+Edward Ng Thanks so much for taking the time to explain the component and its function.
It's my pleasure. Thanks.
I really can't believe they put a one shot non-resettable thermal fuse in the tool, I was shocked when I figured out why mine stopped working, it wasnt even that hot!. It seems to be a case of safety over common sense. Dremels lawyers probably demanded it from some idiot being burned with a previous model.
I can only imagine how many people have blown that fuse and either said screw it and bought a new one or were turned off by Dremel and went to another brand.
I just replaced the fuse with a short piece of solid #14 copper wire. Its been a few years and haven't had a problem. I figure I can let my nose be my fuse. I know that smoldering magnet wire smell very well, lots of experience! Lol!
Many thanks +Edward Ng, you just saved me the cost of a new tool. I did a continuity test on this thermal fuse and sure enough, it was blown. Jumped a #14 copper wire bypassing the fuse and it came back to life! I will replace the blown part soon, Dremel part number 2610009024 (comes as a complete set as a "Brush holder") These are hard to come by, compared to brush replacements.
@@barthchris1 I know that it"s been long time ago but do you think putting an auto reset thermal switch will do ?
Thank you so much sir! I had to shorten the power cable due to the individual wires sticking out of the cord, and after doing that, I was like "Where the hell did this blue wire come from?!'
Thank you very much! I was exactly searching for where the blue wire sits!
The blue wire conundrum! It was bugging me all day. Thank you. Nice hands btw.
You sir, are a gentleman and a scholar.
Also, your video is great quality. Thanks for posting!
Thank you so much! I opened my Dremel up and the blue wire was free floating but I couldn’t find any information about where it was supposed to go!
Thank you very much for this video. I did grout work with my Dremel 4000 and wanted to take it apart to clean it and your video was perfect. Much appreciated Sir!
Thanks very much for the well-narrated and informative video, it was critical in helping me fix my broken Dremel!
Dude! You are the coolest! Thank you so much for making this video! There was no other reason for you to make this other than to be of help. And indeed, helpful you have been. Thanks!
Thanks for a clear and well explained video. Though my Dremel is a different model, I still learned something from you. I have a later '400 Digital' model with an extra black wire (no blue like yours) and very different looking brushes.
Just putting it out there - in case someone reads this comment - where does the spare black wire go? It has a slightly curved piece of copper on the end but there isn't any likely looking component it may attach to.
I might do a question asking TH-cam video - does anyone do that?
Thanks Dave. You saved me from burning out the mother board. I did consider it may have been clipped onto the projecting diode as it appeared covered with a metallic coating. Again thanks
Simon, glad to help.
I watched this vid about 2 years ago. All o had to tembrr was ‘blue wire goes where?’… thanks again.
You helped me. I needed to clean my dremel today. Thanks from Brazil.
Thank you for the video. I was certainly at a loss as to where that dang blue wire went.
Cheers for the video - that blue wire is the exact reason why I watched the video :D
Huge help, saved me a lot of heartache!
thanks my friend, I order a new electric switch for my Dremel 4000 and I intent to replace it by myself, I believe the info provided here will be a great help, when reassembling the Dremel.
Thanks mate, I'm from Mogi das Cruzes, São Paulo Brazil and I can tell you that I've not found any tutorial explaining this as his. Neither the Dremel itself. Congratulations and thank you for sharing your knowledge with us. Hugs! (Google translation)
Márcio, Muchas gracias por sus amables comentarios. Es muy agradable recibir una respuesta positiva sobre mis videos. Por favor comparta este y otros. Como digo, el conocimiento es sólo poder cuando se comparte!
Obrigado amigo, parabéns e muita luz! Thanks friend. Congratulations and God bless you!
Thank you men, you save my life, because i try to replace the thermal fuse and i accidentally move the position of the blue wire and in the moment to reemsamble i dont know where it was connect.
Many thanks from Finland! The blue connector sprung off when opening my 4000 as well.
On another note, the brush assembly plugs aren't threaded in my 2019 euro version, gotta pop open the chassis to remove them... And the chassis still has threads for them. Not sure if it's a global development but somewhat irritating.
the 4000 has the function of keeping a steady rpm even when put under a load..looking at this blue wire and its location tells me its most likely the sensor wire for this rpm feature.being its place is right there with the brushes..where it can since rpm..
I have never seen a video of this quality !! Great ++
Obrigada pelo seu tutorial, estou começando a fazer Luminárias em PVC, é um trabalho muito bonito e artesanal, faço parte de alguns grupos no Facebook, temos muitos problemas com a Dremel vendida aqui no Brasil, para a troca do carvão (escova) temos que tirar toda a tampa, sem contar com o preço dos acessórios que é muito caro. Quando vi seu tutorial até compartilhei com o grupo, mesmo não sabendo falar inglês está muito nítido o que você está fazendo e sei que vai ajudar muitos amigos meus. Obrigada, obrigada, que Deus te abençoe.
Sra Santos,
Muito obrigado pelas suas máveis palavras . Apraz-me que a barreira da língua não foi um problema . Tenho o prazer de ajudar os outros. Saudações do Texas . Deus Abençoe!
+Vanda A. Santos Realmente aqui no Brasil ficou ruim esse sistema de troca de escovas. Meu Dremel antigo era semelhante a este do nosso amigo estrangeiro, e você pode reparar que onde vai aquela tampinha preta da escova nos nossos aparelhos, tem uma rosca na carcaça. Basta descobrir onde comprar as tampinhas de rosquear! Vou tentar, se tiver notícias posto aqui :)
+Gabriel Tessari A minha Dremel é a 4000, vi a tampa mas não quero me arriscar a tirar (por enquanto) e nova ainda. Se descobri alguma coisa será uma boa, quanto mais informações melhor, vou aguardar e desde já agradeço. Até +
+Vanda A. Santos Descobri que o código da tampinha que precisamos é 2 610 006 518, e só é utilizada na Dremel dos Estados Unidos e da Inglaterra. O problema é conseguir a pecinha no Brasil, não consigo nem o porta-escova da minha que queimou o termo fusível de proteção...vou ter que comprar um termo fusível e trocar eu mesmo.
Hi Dave found this today can't believe there was a video titled 'missing blue wire' which was exactly my problem all fixed now thank you
I e baught 3 dremels in the last 2 1/2 years. Now none work with only a few hours on each. Myt last is a 4000. Just like the other two . I was using it, turned it off. Go to use it a few minutes later and nothing. I took it apart and dont see nothing. If it's not to much to ask, any tip are suggestions.
Thank you so much sir for uploading this. Video! I was going crazy trying to figure out where this blue wire went. 👍👍👍👍👍
Its 2019 now, 5 years after you made this it helped me a lot! I was indeed getting crazy about the blue wire :-), My tool is working again thx a lot, if you ever come to Belgium I buy you some beers or other drinks!
Great video! It answered all of my questions about the reassembly of this unit. Most importantly the mysterious blue wire/lead. Thanks!
Thanks for this, just what I needed, my tool got a tad wet and cut out, took apart to dry out and yes that wire could not work out where it went until I saw this, thanks.
Great info. I thank youfor making & sharing this with us, much appreciated.
Thank you. I also wondering where that bleu wire came from. Your video was very helpful. thank you very much.
Love the saying and love the video. I would have enjoyed the section on operation. Im sure someone familiar with the Dremmel would be bored but for those of us who dont know squat. We should be like a sponge to water, Keep Trucking..
Awesome! Thank You! I thought it went there.. After I failed soldering it to the black wire. Hope I didn't F things up. We'll see.. Thanks for solving the blue wire mystery...
Omg thank you so much, I took mine apart last night and that blue wire was MYSTERY
I'm just buying one of these and I'm already downloading this video to future purposes, I'm feeling that I'll need it someday.. thanks dude
That is just what I needed to know, where the blue wire goes... thanks....
Спасибо большое! Ваше видео помогло собрать Dremel, не мог догадаться куда вставляется синий провод. Оказывается под щеткодержатель. Спасибо еще раз!
Dude, this video was so helpful with the blue mystery wire! Thanks!
Hi TX, awesome video!
I live in Brazil and I plugged my dremel 4000 in a 220w jack...
Can you please tell me what are the possible consequences and if it's to hard fixing.
Greetings and many tanks ;)
You've likely allowed the magic smoke to be released from many components. Others may have more technical detail but you may just want to buy a new one. Glad you liked the video.
Following these steps didn't get her working again, but was a very methodical, detailed and practical vid. Very happy I watched and read the comments because Ed Ng's comment will be my next step in trying to un-shit my Dremmel. It died drilling a piece of fucking cedar!!!
I am impressed that you put this up. Thanks. helped a lot.
This was super helpful with the wiring in reassembly!
The blue wire is not a feedback to the microcontroller as stated below in the comments section. Microcontrollers with feedback circuitry are used in DC BRUSHLESS motors to sense direction of rotation and speed. The type of motor in your Dremel 4000 is an old school universal motor (been around for a century). This motor can work on DC or AC hence the name universal. In its application in the Dremel tool it receives a pulsed DC input from the controller. The blue wire is simply the neutral return to the speed control board. This is also old school (it's a pulse width modulator to control average voltage/speed to the motor).
There are a number of complaints on the internet about these Dremel motors arcing/running rough/ and buzzing. An educated guess from someone with an electrical engineering background.. I think this is due to this blue wire's friction-only contact with the brush holder which under vibration could cause arcing and rough running. This would only get worse as the tool gets older with use. On the current models sold in Australia (in 2017) they have done away with the removable brush caps (so the brushes are no longer serviceable). The tool I bought today is running rough from new with an arcing sound at all speeds - very noticeable at speed 17 on the controller potentimeter. This happens to coincide with harmonic balance vibration at this speed. Since it is faulty from new I'll be returning it tomorrow for refund. When Dremel bring out a brushless version I might be interested again.
Thank you for this. You explain all the items/steps really well!
Thank you for this video. There is a part missing off of my dremel and I had no idea what to look for. Hopefully I can find it now that I know it's a brush cap and and know what to look for. Thank you again. :)
lol i was so lost with the blue wire,.... thank you, much appreciated.