Battery Spot Welder (CD Welder) || DIY or Buy

  • Published on Apr 1, 2018
  • Where to order 10 PCBs for $2:
    Circuit project files:
    Previous video:
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    Make your own Li-Ion Battery Pack:
    HACKED!: Microwave Transformer becomes a High Current Transformer:
    Functional CD Welder project:
    You can find more information about my failed project here:
    In this not planned episode of DIY or Buy we will have a look at my failed CD welder project. During the video I will show you how I designed the project and demonstrate how around 90% of it works. At the end though, I will tell you why this project failed and thus show you that buying can save you a lot of nerves.
    Thanks to JLCPCB for sponsoring this video
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    2011 Lookalike by Bartlebeats
    Killing Time, Kevin MacLeod
  • Science & TechnologyScience & Technology

Comments • 1 056

  • Mike Studmuffin
    Mike Studmuffin 7 days ago

    I want my 8 minutes back

  • Chase Rayfield
    Chase Rayfield 8 days ago

    You don't use any flux!!!? That is why your soldering seems shitty... get some good MG Chemicals flux in a syringe and apply it where you will solder and it will be like magic.... Also I tend to wet the tip of my iron with solder and apply it that way, as long as you contact the component long enough to prevent cold joints this is fine. Also... I wuold have just desoldered the FETs and made an air wire for your reference... ignoring the PCB ground.

  • Fede Devi
    Fede Devi 10 days ago

    Using a big 12V lead battery for 50$

  • MrPhoenix2u
    MrPhoenix2u 13 days ago

    I'm really struggling to see how adding a reference potential to the mosfets as an afterthought will short out the main power supply. Isn't the voltage at the gate not connected to the drain and source? Wouldn't the data signals going to the gate be a completely separate circuit? Isn't the fact that the gate is missing a reference potential proof that the gate and source aren't continuous?

    It's so incredibly difficult to learn all of this. I was scrolling through comments looking to see if anyone had already asked my question and I found a comment from myself 4 months ago trying to figure out capacitors haha.

    Edit: Okay so after a week of deciphering this alien language I've come to the realization that he doesn't care about the gate potential. For some reason he doesn't need a pull-down resistor for the gate. My best guess on how to fix this as of right now is to connect Cap- to ground. How that shorts the power electronics I have no idea.

  • SJ SES
    SJ SES 20 days ago

    be simple like use module xxx not diy by uself.. make me dizzy..

  • J. Lietka
    J. Lietka 26 days ago

    if that small welder got to working, it could be used to connect 18650s (via nickel strip) together, right? thanks again

  • FD
    FD Month ago +1

    you are very very "challenged" when it comes to soldering

    • Chase Rayfield
      Chase Rayfield 8 days ago

      @FD Yes exactly I used rosin core solder in college as it was all I knew or had and experienced just this same thing. It's a pain in the neck heh...

    • FD
      FD 8 days ago

      @Chase Rayfield that i don't doubt. before i got extra flux, if i stayed too long on a pad, or wanted to reflow a joint and the rosin was all gone i would end up with horrible joints if i didn't apply a bit more solder.

    • Chase Rayfield
      Chase Rayfield 8 days ago

      @FD Yes rosin core doesn't hurt.... but neither adding flux or using rosin core solder at all is a recipe for bad terrible soldering.

    • FD
      FD 8 days ago +1

      @Chase Rayfield ok thanks. i will say that louis rossman uses rosin core and a ton of flux with it. he probably does more smt soldering than anyone, manually atleast. so i guess the key is just flux everywhere.

    • Chase Rayfield
      Chase Rayfield 8 days ago

      @FD Nope I never use it and many people you can watch on youtube doing SMT soldering dont' either you'll get better joints with separate flux and solder with less skill, granted you may be quite good at your particular technique. Note that if you use separate flux and sodler your joints will typically be cooling slower since you have more flux and can apply the heat for longer, meaning fewer cold joints. Also note the solder he is using there appears to not be rosin core soldier just solid solder.... its a wonder he gets it to work at all that way. If there were any rosin there would be a bit of smoke...

  • ErCapoAlex
    ErCapoAlex Month ago


  • Frank-T
    Frank-T Month ago

    Just as I thought. Why not buy one that really works well out of the box for 200€

  • cynth0984
    cynth0984 Month ago

    I think that with that accent you can achieve anything :)

  • Dave Fredrock
    Dave Fredrock Month ago

    Thank you so much for sharing. It's very informative and interesting to watch how you went about the challenge. Despite the project not being exactly what you wanted, hopefully, after the frustration dies down, you'll find invaluable lessons learned. This stuff was way over my head but it's inspiring.

  • Rubicon
    Rubicon 2 months ago +2

    "Spoilers, I'm going to fail terribly. Let's get started."
    Advice to live by...?

  • Melvin K Varghese
    Melvin K Varghese 2 months ago

    I like the way you talk

  • Benduino
    Benduino 2 months ago

    Great video! My deep respect for you, to admin mistakes and willing to publish them! This way even we can learn from your mistakes. How great is that!
    Love your channel!

  • Rhys
    Rhys 2 months ago

    Sometimes complex isn't always the way to go. Start thinking less sophisticated, then you'll get the result you've been wanting.

  • Abdullah Yasir
    Abdullah Yasir 2 months ago

    this channel is Awesome

  • hammad :
    hammad : 2 months ago +1

    Make a video build a battery Capacity Tester Using arduino

  • Peantbtter sandwich
    Peantbtter sandwich 2 months ago

    Thanks for sharing... Alot of DIY'ers post video that are successful and don't or rarely show the disadvantages. You my friend are a trust worthy guy and your videos seem more authentic. Good job. After all failing is how we succeed ! 👍

  • Chris Burn
    Chris Burn 3 months ago

    I like your honesty, even when you fail due to errors we all do with projects, you still present valuable informtive and clean instruction as to why. Thank you keep it up

  • Terry Tyler
    Terry Tyler 3 months ago

    Wicked Job!

  • Dustin Eward
    Dustin Eward 3 months ago

    The failure is fine. That you gave up is not...

  • Anirban Mallik
    Anirban Mallik 3 months ago

    Use a microwave trasformer destroy the secondary coil add pwm watch Creative Chanel..

  • Seshasai Maddela
    Seshasai Maddela 3 months ago

    Hey Scott
    I am having a great time watching all your DIY videos and I really appreciate all your hardwork in explaining them to us.
    I thought to ask a question like "why can't a flash circuit from old roll cameras used to make a spot welding machine to connect lithium-ion batteries".
    I really appreciate your time to reply me.
    Thanks and keep scotting 😊

  • jose pedro Ribeiro
    jose pedro Ribeiro 3 months ago

    Coloque legenda português

  • Michael O'Toole
    Michael O'Toole 3 months ago +1

    You were almost there, you can fix it but... practice soldering more ;)
    Love the videos....

    ANDY DJ 4 months ago

    B u y wins

  • dbuezas
    dbuezas 4 months ago

    Es ist super, dass du auch die fails hochlädst!

  • ExCalibur
    ExCalibur 4 months ago

    simple car battery makes powerful spot weld.

  • Martin Lanza
    Martin Lanza 4 months ago

    There is a really good arduino spot welder here at a good price:

  • Mfreiher
    Mfreiher 4 months ago

    Hi. great work. I was wondering if this timer could be used with a battery?

  • Ins@neAju
    Ins@neAju 4 months ago

    Great one scott

  • Jean Valjean
    Jean Valjean 4 months ago

    Impressive video... Nice work

  • BeginnerLockPickingDiaries

    How many light bulb prototypes were made before one actually worked? Try, try, try try... Try try again!

  • Michal Jedrzejek
    Michal Jedrzejek 5 months ago

    hi, can i gent e-mail to you?

  • MrPhoenix2u
    MrPhoenix2u 5 months ago

    Why would you hook up the 100F capacitors in series? Wouldn't you want them in parallel so they add to a total capacitance of 600F?

    Edit: Oh wait energy formula is (1/2)(C)(V^2), so you would want to increase voltage as much as possible, nevermind.

    • Xfactor Chem
      Xfactor Chem 4 months ago

      Energy wise it does not really matter. While your formula is correct you have to keep in mind that wiring capacitors in series will reduce the total capacitance which perfectly cancels out what you gain from the voltage squared term.
      For a capacitor with C=1 and Vmax=1. In case of 6 parallel caps Ctotal=6C and Vtotal=Vmax. While for series Ctotal=C/6 and Vtotal=6Vmax. Plugging these values in your equation will show you that the energy is the same in both cases.
      My guess would be that he wired them in series so he doesn't need huge currents going trough the MOSFETs.

    THEBIGMEOW 5 months ago

    Could you please make a Single Supercapacitor spot welder
    Pretty please

  • Cheas Moon
    Cheas Moon 5 months ago

    Where did you learn all this

    • DaffyDaffyDaffy33322
      DaffyDaffyDaffy33322 5 months ago

      The best way to learn this stuff is to do it yourself. Find a project you wanna do and do it!


    please sub me

  • Franklin Binas
    Franklin Binas 5 months ago

    Try to use photo flash capacitor you can get that capacitor to old camera that having a flash

    • DaffyDaffyDaffy33322
      DaffyDaffyDaffy33322 5 months ago

      While those can zap you, they don't hold *that much* power. Not enough to weld with at least.

  • Do it Yourself Channel
    Do it Yourself Channel 5 months ago

    Aber eine Coole Idee ist es :-)

  • Daikataro Kamegawa
    Daikataro Kamegawa 5 months ago +1

    Am I the only crazy individual who sees a simple relay as a solution? Just connect the normally closed contact to the capacitor bank charging, so when it's not in use, it's charging up to the desired voltage (interrupt current flow via Arduino, can be even done via traditional electronics), and use the pedal switch to energize the coil, and connect the normally open to the welding terminals, so you short the capacitor bank while you keep the pedal pressed AND disconnect it from the charging circuit at the same time.

    Add a second always energized relay, with its normally closed contact connected to a discharging resistor, so that when the welder is powered, it works normally, and when it's unpowered, leftover charge is simply discharged as heat, to avoid unpleasant surprises.

  • Ashton Docter
    Ashton Docter 5 months ago

    Why would you hook up the caps in series and not parallel

  • InfernoVortex
    InfernoVortex 5 months ago

    If you succeded on the first try how would the prices compare? Would the DIY working one be worth it over the bought one? How efficient would they be comparatively?

  • Ashish Kushwaha
    Ashish Kushwaha 5 months ago

    I always like your videos. But this time unlike. Was expecting mature circuit and schematic design. Anyway nice try.

  • electroumit
    electroumit 6 months ago

    You telling perfectly. You drawing perfectly. I like your voice. Thank you.

    TRIBLE E 6 months ago

    Sir, you dose not explain clearly like "electro boom" are not clear and so selfish..I DONT LIKE THAT

  • Prashanth
    Prashanth 6 months ago

    That's too bad it didn't work out! Great work though! :)

  • Nebil Ucak
    Nebil Ucak 6 months ago

    Can you send the arduino code if possible?

  • Audio Engineering
    Audio Engineering 6 months ago

    Hi Dear
    which software you use to design the diagram and pcb?
    tell me name Please

  • Sc6outer
    Sc6outer 6 months ago

    wait ure from germany??

  • transformer889
    transformer889 6 months ago

    I made a very simple device with a large capacitor and a thyristor it is simple and works.

  • Hendrix Junior
    Hendrix Junior 6 months ago

    some of your projects you should sell them already built for us your followers buy them

  • pomonabill220
    pomonabill220 6 months ago

    Well, you can't say you didn't TRY! At least you were able to figure out where your mistake was! and show us.

  • Jansher Khan
    Jansher Khan 6 months ago

    Hahh honest man

  • Péter Kocsis
    Péter Kocsis 6 months ago

    i wery like wen somebody spoilers da storiiiyyyiiy

  • Ray F T
    Ray F T 7 months ago

    Awesome, you have another sub, for being honest. oh and i do like your vids !! Cheers

  • れいなーちゃんゆっき


  • John Q
    John Q 8 months ago

    Great video.

  • Flight Therapy **BullisticFPV**

    What was the name of the free PCB design tool again?

  • Chabo C.P
    Chabo C.P 8 months ago

    Con los errores aprendemos, así la siguiente vez, saldrá mejor. Gracias.