How to Make Your Own DIY Spot Welder for 18650 Lithium Ion Battery Packs

See how to make your own Spot Welder. Handy if you are making battery packs with 18650 lithium ion batteries. I use a timer to control how much time current is passed through the welding pen and make a handheld momentary trigger to control the electronics. This welder is deisgned to work with automotive or garden 12V batteries and is easy to put together and use!
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Link to Welder electrical schematic bit.ly/2WJziPo
Below are affiliate links to parts I used in this project:
Starter Relay: amzn.to/3bC5ZEX
Timer Circuit: amzn.to/2S5277u
8 Gauge Cable amzn.to/3awOGDL
Terminal lugs amzn.to/3bw7Z1k
Momentary Switch amzn.to/3aEcci5
You can read the written version of this article here: bit.ly/2Wp1EzJ
Complete Instructions on the Drok Time Delay Module: • Programmable triggered...
Closeup Wiring #1 bit.ly/2MVl7Cy
Closeup Wiring #2 bit.ly/2HIqS7i
Here's a correction provided by a viewer. I should know better considering I've been in IT for over 40 years:
0.01s = 10ms = 1/100s
0.001s = 1ms = 1/1000s
#batterypack
#lithiumionbattery
#spotwelder
0:00 Introduction
0:23 Materials Used in Project
1:46 Mounting the Relay and Timer Circuit
2:06 Crimping the lugs and connectors
3:47 Making a Trigger
6:02 Wiring the Timing Board
7:45 Programming the Timing Circuit Board
8:54 Wiring Diagram Schematic
9:08 Overview of the Wiring
10:45 Testing the Spot Welder
12:37 Wrapup

[@ExtremeDIYGuy]

I've received several requests for a video on making the spot welding pen. I've recovered the footage I needed and posted a video on the welding pen kzbin.info/www/bejne/onycdI2PgKyZrtU , I hope this is useful to you!

[@joeschreffler5993]

The link is 404 Not Found.

[@joeschreffler5993]

Sorry, my fault. Apparently the fault of "Unshorten Link" extension for Chrome. I turned the extension off and it worked.

[@ExtremeDIYGuy]

@@joeschreffler5993 That's interesting to know. Thanks for the heads up!

[@stevemcmechan6444]

@@ExtremeDIYGuycould you have done away with the manual press switch and wired those 2 wires to the welding pen also so that when the pen touches the metal strip that shorts the trigger wires which then does the same function as you did manually pushing the switch? Just a thought.

[@alexprice1443]

This looks like the simplest and most effective spot welder build for batteries that I've found on KZbin. Thanks for making this vid, hope to build my own soon

[@ExtremeDIYGuy]

Glad it was helpful!

[@sethreign8103]

Boy do I ever miss straight to the point, no time wasting bs, or distracting music content like this 😁

[@ExtremeDIYGuy]

I try keep my videos straight forward and informative.

[@stumitchell3515]

This is absolutely brilliant. I built it using the wiring diagram and set the timer using a tutorial after a quick search. I think I spent less than 50 CDN, not including the battery. Worked perfectly after adjusting the time to 9 milliseconds. The only changes I made was to make the switch foot operated and to build a handle that allows the copper probes to be adjusted for width of weld. Great tutorial; Thanks so much!

[@ExtremeDIYGuy]

I'm glad you liked the video! Your welcome

[@LaLaLand.Germany]

Thanks Mate! I found just the stuff You used (timer/relay) and will put together my own rig. This is so simple and awsome- just what I was looking for. And it seems to deliver very good results. I´m gonna apply a footswitch and use two welding leads (both hands). Then I got just what I need to tackle 18650 builds- Awsome!

[@ExtremeDIYGuy]

Glad it helped

[@davidfarmer2049]

Very detailed. This gentleman has a talent for explaining clearly.

[@bkajebeukseb4726]

Excellent video. I just made one following your instructions here and on the written link. I used it to spot-weld 3V Li-on button battery for my ham radio (I had to cut the impulse time down significantly ;-0). Works great. Spot welds are easy now. Can't wait to make up some 18650 packs. Thanks for posting.

[@ExtremeDIYGuy]

Glad it helped! I have raw footage on making the pen, just havent had a chance to edit it and put it up yet. I'm glad this was helpful to you!

[@rocketman2149]

@@ExtremeDIYGuy Ever finish the pen video? I want to make one

[@ExtremeDIYGuy]

@@rocketman2149 I actually recovered the raw footage from old backups so plan on putting one out sometime soon.

[@rocketman2149]

Jose's Extreme DIY no problem I printed out the written copy from website, thank you though. Your videos are awesome!

[@ExtremeDIYGuy]

@@rocketman2149 Thanks! I appreciate the positive feedback!

[@vvctailor]

Thank you very much for this video. After making several attempts with a microwave transformer, i decided to give this method a try and it works!.

[@ExtremeDIYGuy]

Good deal, I'm glad to hear that a) your safe from the transformers and b) that this was helpful!

[@stumitchell3515]

Man those microwave transformers are pretty scary dangerous!! This method might end up with a burn but it wont kill you!

[@leochen4891]

best diy spot welder I have seen so far. Thanks for the video.

[@ExtremeDIYGuy]

Your welcome! Glad you enjoyed the video.

[@leochen4891]

I have built one with your design, and it works like a charm. Thanks for the great tutorial.

[@toosavvy3504]

@@leochen4891 Built NOT Bought! The key to saving a dollar :-) Very plain, clear presentation & demonstration. Impressive tooSavvy @UK

[@aalhout]

Most useful video for how to DIY Spot welder👌👌👌....Thanks for the effort and your time 🌹

[@ExtremeDIYGuy]

Thank you for watching!

[@ryannichols2202]

Trouble shooting the solonoid. I wired up the diagram and had no luck. But i traced the problem. The soloniod negative is the back mounting plate. Not the second small terminal on the relay. That is actually for a coil. But in this aplication isnt used. So for the solonoid to fire you apply the 12v signal coming from the timer to the s terminal on the relay. And the i terminal isnt used. The ground wire is grounded to the mounting plate. Just like it would be grounded to the car body. I hope that clears up the people who are having trouble getting it to work. Great job jose awesome video. Im now a subscriber.

[@ExtremeDIYGuy]

Thanks, hopefully that helps other viewers. The back mounting plate on mine is grounded as I attached the neg cable to it on both sides of the bolt. I did attach a ground to one of the small terminals on the front and the trigger (+) output to the other.

[@gregorytrenhed8318]

Thank you again for the work you put into this. I was using a bench top power supply but now my relay is only getting 3+v when triggered, went straight to battery like your and I’m off and running again. Kids need there dune buggy battery before snow fall.

[@ExtremeDIYGuy]

I'm glad you had success. Better put a charger on the battery before giving it back to the kids! :D

[@gregorytrenhed8318]

I was building them a 7s 5p was maybe a little to big to start and my main wires were a little to big trying to finish 4s 5p to get them rolling again.

[@ExtremeDIYGuy]

@@gregorytrenhed8318 Good deal, post your results here!

[@30roundclipazine79]

I made essentially the same setup with a cheap starter solenoid from Amazon and while I was practicing on a bad cell the relay got stuck closed and melted a hole right through the bottom of the 18650. Luckily it was completely dead and didn't explode. I'm considering having two relays in series as a safety redundancy to protect myself and the batteries.

[@klaudyuvl]

U can put a 300A fuse after the selinoide and u are ok,it's 3$

[@30roundclipazine79]

@@klaudyuvl I considered this just didn't know the amperage to use thanks

[@stevesplace7230]

I should have come here before I purchased all those stupid cheap non-working spot welders on aliexpress. Your design works great! I mean, I sat down this afternoon with three tin cans and large spools of three different sizes of nickel strip. Bet I made 500 welds. Wires didn't get hot. Solenoid didn't get hot. Pen (electrodes) didn't get hot. It just works. It just works over and over and over! Pressure on the electrodes does make a difference. Would like to be able to set the timer at hundredths of a second increments instead of just tenth of a second increments but that's nit pickin. Thanks again. Now to find a use for welded up tin cans.

[@ExtremeDIYGuy]

Steve, That's one of the best compliments I've ever received! I'm glad this worked out well for you. I'm curious as to what timer you used, the one in the link will let you refine it the 100ths of a second. But in any event, keep welding and let me know if you figure out what to do with the tin cans lol

[@stevesplace7230]

@@ExtremeDIYGuy I'm using the Drok timer you linked to above. Drok says it cycles at 0.01s-9999mins. But, the instructions I downloaded for the 35238-MP Mult-Function Timer clearly states .1 second Resolution. Makes no sense to me, but, neither do women. I'll play with it (the timer) some more tomorrow, if I can find some more cans. Thanks again.

[@davidvaeyens2188]

Works great !!! THANK YOU...greetings from Belgium..nice video..end succesfull

[@ExtremeDIYGuy]

Your welcome and thanks for watching!!!

[@chrisdaniels4674]

Thank you. Your the dad I wish I had.

[@ExtremeDIYGuy]

That's a compliment of the highest order.

[@balakrishna7134]

Thanks for the amazing video, it helped a lot

[@ExtremeDIYGuy]

Glad it helped!

[@joshsimmons8178]

Thanks . This was way better than buying a welder that either A: wasn't going to work well per the price of amazon welders being too cheap and inconsistent. or B: the cost being WAY too high for anyone to want to even pursue battery welding in general.

[@ExtremeDIYGuy]

I'm glad you enjoyed the video!

[@Hoss_1966]

Hey thanks for the video, I have a question, I have mine all set up, relay makes clicking noise like yours does when no oad on it, but when I have the pen on the metal and press the trigger, then I get like a grinding sound from the solenoid. Not sure why. I tried setting time to 5 sec, press trigger, then quickly touch the pen to the metal, I get a very little spark, then a P11 comes up on the screen. Any ideas? I do Have a slightly different timer than you, but I have all setting the same. Thx

[@electricalfive2248]

awesome, welds great

[@ExtremeDIYGuy]

Thanks! I've gotten some good welds with it!

[@markh.2899]

Thanks, very cool!

[@ExtremeDIYGuy]

Thanks!

[@markh.2899]

@@ExtremeDIYGuy Thank you, we'd sure like to see ya do the pen build... Take care!

[@N8904V]

Thanks... Will do it..

[@ExtremeDIYGuy]

Sounds good. Good luck!

[@chriso5923]

Nice vid and thanks for the info. I would put a diode across that relay trigger. I've killed a solenoid before not doing it. When the field collapses, it creates a reverse current that can damage it.

[@ExtremeDIYGuy]

I'm assuming you would put it in reverse normal polarity?

[@chriso5923]

@@ExtremeDIYGuy Yes sir.

[@klaudyuvl]

Did u had the controller board when u burned it?

[@klaudyuvl]

i'm building one now and i don't have a diode to put in my parts

[@bgable7707]

Nice Job, suggestion for future video's. Show an up close final product(usually in the beginning) and the components used in one frame for several secs. Oh, I found that @ 9:08. Great work thanks

[@ExtremeDIYGuy]

Thanks for the idea!

[@stevemcmechan6444]

@@ExtremeDIYGuycould you have used the pen itself as the trigger so when it shorts against the nickel that does the trigger command instead of you pushing the button? Or would that blow up the pcb timer board maybe?

[@FortunateSniper]

Can you upload more pics. Especially the back and how the wires are connected. For the life of me I can't get it to work. Appreciate your vids!

[@ExtremeDIYGuy]

Thanks, Let m eknow if these two files help any. They are in the comments but they helped someone that asked for them earlier. Closeup Wiring #1 bit.ly/2MVl7Cy Closeup Wiring #2 bit.ly/2HIqS7i

[@ExtremeDIYGuy]

I connected the ground wire from the back of the unit to the battery using the bolt that holds the relay on as a connection point. I then used that bolt and the plate of the relay as a ground point for everything that needed it. It sounds as if the plate of the relay isn't grounded? You need to make sure that the back plate of the relay is grounded as well as one of the small terminals in the front. When you apply current to the other small terminal, the relay will close.

[@eroticmasterbaker]

I made a welder like that but without the control board and it worked great for a bunch of welds but now it stopped welding. I bought a new solenoid and it still won't work . I charged the battery and tried two batteries. Do you think my momentary switch just isn't activating the solenoid for long enough and I need a control board?

[@ExtremeDIYGuy]

Probably so, worth giving it a try

[@shandoli]

great video. Do you by any chance have access to an oscilloscope? It would be interesting to see the actual time at the pen tips considering there are two mechanical relays in this circuit.

[@ExtremeDIYGuy]

I wish I had one, have thought about trying to build or buy something to integrate with the phone to use as an o'scope.. I could use one to diagnose ignition issues as well but no I don't have one. But that would be interesting to see. Probably significantly different times that the control module is set for.

[@mikehotchkiss8975]

@@ExtremeDIYGuy I got a used one for free. These is not much of a value for old stuff like this. To me and you yes....

[@ryujiyamazaki583]

Hi, Thanx for the amazing video, respect! Can you please tell me what current and volts are going towards the Solenoid? 12V and how many Amps? Thanx in advance 😊

[@ExtremeDIYGuy]

Battery was 12v and I believe rated for 860 cca. I don't know if that was the amperage flowing through it as I did not measure it but the potential was there. It really all depends on the capacity of the battery you have hooked up to it. That is why I put a timer circuit on it,. The more amps the battery is capable of, the less time I want it passing current. Does that make sense?

[@lanemeadows9957]

Awesome video. I've got everything from your links. Got the tiimig board programed. Got the main lug terminals to the battery and pen. I can't read the wire diagram to go from the timing board to solenoid. Could you upload a close up picture of the wires from the timing board to the solenoid? Thanks!

[@ExtremeDIYGuy]

I added two links in the description, closeup wiring #2 shows the black wire going back to a common ground point. YOu could really ground it anywhere and it will work.

[@lanemeadows9957]

@@ExtremeDIYGuy Thanks! I might have a bad solenoid. I ordered the one from your link but it can in red color not black. I cant get any current on the large pen lug. The meter spikes when I go across the 2 smaller bolts.

[@ExtremeDIYGuy]

@@lanemeadows9957 Should have ground on one smaller lug and the relay should close when you apply + to the other. There will be a resistance reading between the two which is normal because there is a coil operating the relay. Try one more thing before returning. Run a piece of ground wire to the solenoid frame where the bolt goes through as well. If I remember correctly, I think I had do that to get it to work.

[@lanemeadows9957]

@@ExtremeDIYGuy Its alive!!! Grounded all the negatives together on the solenoid chase then to the battery. Got the spark on the pen! Thanks again!!

[@profitbazar6569]

So nice

[@ExtremeDIYGuy]

Thanks!

[@sumitk2521]

@Jose's Extreme DIY Hey can I use any other power source instead of car battery like maybe direct pluging to switch board or something??

[@ExtremeDIYGuy]

I don't think you would get the amperage you would need unless there's a large transformer in the mix. Also, 12 volts is relatively safe to work with. You would be dealing with unknown voltages, I would advise against it.

[@cwmaxfield2000]

Can this be used for spot welding anything. I need to tack a fender on a Van. Just enough to hold it temporarily.

[@ExtremeDIYGuy]

If you connected the cables to a spot welding jig. that might work

[@pauljindra2057]

Hello and Great Video. I am a non-electrical person and hoping I'm not too elementary to ask what power source did you use to power up the Timer Circuit board for setting the programing? Dis you just connect to the car battery?

[@ExtremeDIYGuy]

A 12 volt car battery was used to power everything. I hope this helps

[@guillaumevincent716]

you have a new subscriber

[@ExtremeDIYGuy]

Thank you!

[@ryanrose8856]

@Jose's Extreme DIY -- Did you post the correct link to the timer circuit? Can I set the delay short enough not to burn through the nickel strips or my batteries?

[@ExtremeDIYGuy]

Yes, the link in the description is the timing circuit I ended up using. It gives you control over the timing, you can go as low as 1ms.

[@theborednerds]

Hey Jose, thanks for the demo and the write up. I used your affiliate links for the timer and relay! Have you had any issues with the DROK? I got through about ~20 welds (a few tests to tune the timing and 7 cells welded) and now it occasionally gets hung up when trying to fire the solenoid. Cycling the power on and off resets the timer, but as soon as I short the starter with a weld, it fails. I'm wondering if the system needs an actual ground (vs just the neg terminal on the battery)? Also, I ran into an issued during assembly that I think others might find useful: the negative/ground for the starter relay runs through the mounting bracket, not through the 2nd post on the solenoid. This is sort of a gee-wiz after assembled, but if you follow your wiring diagram and photos, you will not succeed. I think you got lucky because you ran the negative through your frame and just happened to attach it to the mounting bracket.

[@ExtremeDIYGuy]

I'll have to take a hard look at that diagram. I actually ran the ground through the mounting bracket intentionally, thos relays are fussy and need a ground at the bracket as well as on one of the front posts. Mine is holding up well, I haven had it hang up on me. I've done about 100 welds through it with no problems.

[@theborednerds]

Yeah, I don't know what changed, but I have welded another 60 cells without issue. There are comments on the Amazon listing also describing the use for the other smaller pole. I think it's for an indicator light.

[@ExtremeDIYGuy]

@@theborednerds At least it changed for the better! The smaller pole on the drok? The output side one is NC and the one I used is NO.

[@settingshadow]

Can i use dual output 12v 50A smps to power the whole thing?

[@ExtremeDIYGuy]

I would think so, 100 amps should be enough juice to work.

[@martyburns3096]

Jose, Love the video. Just made mine using all your products in the description. Tested it only a few times connected to my car battery. I have a question about the trigger. When I push it it fires, but it will continue to fire repeatedly unless I let go of the button. Is this normal? I "expected" to push and hold the trigger, the board would fire to the settings programmed, but it would only fire again after I released and pressed the trigger again. Can you help?

[@ExtremeDIYGuy]

Marty, that's not normal. I had that happen a few times when I was first testing the build, If I remember correctly I went through all of the connections one more time, especially the ground connections and that resolved the rapid firing.

[@JCHaywire]

Mine does that. So after frustrating troubleshooting--I actually rebuilt it completely! It did the exact same thing the second time. So I'm getting something consistently wrong. If you press the electrodes on something nonconductive, it clicks once and won't re-fire until I press the button again.

[@Roccoc-zh2im]

I watched your video and put a unit together. When I try it I get a spark and doesn't look like enough power. Using a Riding mower battery 12VDC with CCA of 135 A. Then placed 2 similar batteries both 12VDC and CCA 135 A. Still not enough to cause a weld. What size batteries should I be using. (Cost conscious).. What would be the minimum size, CCA, to cause a weld. Also, can you provide, or show, the actual wiring.. Thank you

[@ExtremeDIYGuy]

Hard to say, I would think that 135 should work. I used a car battery rated at 500 CCA.

[@Roccoc-zh2im]

@@ExtremeDIYGuy Sorry, Please advise if I have it wired correctly: If you hold Solenoid with large terminals up and the smaller terminal down, the left (large) I connect to the + battery, + input to timer board, Trigger switch, NO (middle on right) on timer board, 2nd lead to welding pen From Trigger connect to top terminal on left side of timer board Ground from battery (-), I connect to (-) input to timer board, 2nd input on left side of timer board, First lead on the Welding Pen, and Smaller terminal on right side marked (I) on solenoid Left side of small terminal on left side of solenoid marked (S) to right side of timer board, NO (3rd) position Do I have this right? Should I change anything? Again I apologize but would really to like to get this thing built correctly

[@rocketman2149]

I am having a horrible time trying to fit 3 wires into the small positive holes on the control panel. I'm using 14 gauge wire. Did you use the bell wire to wire controller to solenoid and battery? Could I attach all the 3 wires going to positive on the control board together on one side of a butt splice connector and then on other side of butt splice connector have one wire running to positive on control board?

[@ExtremeDIYGuy]

I can see that, I used bell wire for all the connections to the small controller. There isn't much room in those connectors !

[@coolarrow9127]

I had ordered the parts before your came up as a suggested video, the solenoid was a 500a solenoid, do you know what kind of current you are flowing? I guess its gonna depend on the battery used and the amount of current available minus the resistance in the circuit. does yours build up much heat? I also ordered some cooper stock that seems larger that the one you are using, i have a question though. Why do i see everyone bringing the ends to a point? I left mine flat, i would think that flat would be better to dissipate the heat/spark at the tip, and as long as you have enough current available. my thinking is that this would aid in the life of the tip as opposed to all the energy eating into the copper tip, i guess ill see... lol I just ordered the controller but all the other parts are in and ready. Its funny though, great minds think alike, after a lot of research i came up with the same simple design as you for relatively cheap compared to whats available commercially. Thanks for this video and easing any fear i had that it would not work, now i'm pretty sure its a good design, especially for my needs.

[@ExtremeDIYGuy]

I have not measured the current but it is certainly pretty high. I'm not even sure that using an Ammeter would capture that since the current only flows for a few milliseconds. But I believe you are correct, it depends on the battery you are using and what it's capable of. Which is why being able to adjust the time is critical. I put points on my pen with the concept of being able to pin point the current flow. also, the commercially available ones have points on the electrodes. I can see your point on leaving it flat though. As long as it works!

[@DukeOfSouls]

I have the timing board and relay hooked up to 2 12V 5ah batteries connected in series. I cant get the heat needed to weld and the solenoid to stay clicked in. Keeps rapid clicking every time the pen has contact and i dont know why.

[@ExtremeDIYGuy]

Try running the batteries in parallel for more amperage.

[@DukeOfSouls]

@@ExtremeDIYGuy oh my bad didnt mean to say series. They are in parallel. Finally got spark but the solenoid is still rapid clicking every time i try to weld. The heat dosent go through the strip.

[@zing913945]

Excellent video and project Well Done !!! Can you share the information on the second board you used and the results ?

[@ExtremeDIYGuy]

This is the link to the second board amzn.to/2S5277u/ Results were great since I could control the time to the millisecond. Nice clean welds.

[@zing913945]

@@ExtremeDIYGuy Thank you I have all my parts except the board. The link went to the main page of amazon instead of the Board. Thanks for you help !!!!!!!!!!!! What a cool project

[@ExtremeDIYGuy]

@@zing913945 They may not have anymore available on Amazon. You can buy one directly here. THis gent made a great video on how to use the board and deserves some sales

[@stevemcmechan6444]

@@ExtremeDIYGuydid you have the name of that second new board as when I click on the link I don’t see anything sadly.

[@jhonydelacruz9189]

Sir i had watch your video on DIY spot weld. sir i have a question can i use 12v/3amps. regulated power supply for the power source?

[@ExtremeDIYGuy]

I don't see why not, worth a shot. Not sure 3 amps is enough though.

[@jhonydelacruz9189]

@@ExtremeDIYGuy Tnk u sir for replying to may question, regards

[@davidv7371]

Unfortunately I am getting short on the timer. If I unplug the common or unplug "NO" then no short, timer works fine but no weld/spark. While they are connected the the timer goes nuts, just keeps firing off when I press the button vs the timer countdown. Any idea's, could I have a bad timer?

[@ExtremeDIYGuy]

It sounds like the timer is in the wrong mode. But it could be a bad timer as well. I would start by going over every wire connection to make sure it is correct and securely fastened.

[@bethbriggs9934]

I just got my setup assembled. Everything seems to be working but I'm not getting any weld. I have a motorcycle battery with 335 cold cranking amps. Do you have any trouble shooting tips to figure out what is off? I got the same timer board and solenoid and followed your pen instructions so it should be the same machine.

[@bethbriggs9934]

Another bit of information. When I fire the welder with the pen in the air. The timer just fires once when I hit the switch. When I have it in contact with the strip, it will fire repeatedly. Not sure why. I bought this off of ebay: Pure Nickel Plated Copper Strip Tab 0.15mm x 8mm. I've read somewhere that you need pure nickel. Is that my issue?

[@ExtremeDIYGuy]

It sounds as if the battery doesn't have a sufficient charge to weld. I would check the voltage on the battery. I think the strips you are using might also contribute to the problem of not welding, I would definitely a pure nickel strip. I'm not sure why it would fire repetitively under load. It might be that 12v relay contacts bouncing but that is unlikely. I would make sure are the connections are tight, definitely make sure you have a good ground.

[@bethbriggs9934]

@@ExtremeDIYGuy I'm not 100% sure what is going on. I can get it to work sometimes. Once in a while I get a spark from the clip on the battery terminal. The batter is reading 12.9 volts so it's got a good charge. I've tightened up connections and played with the timing board. When I do get it to fire, I don't get a weld but that could be the stip. When I ordered it it said Pure Nickel then I realized it was pure nickel plating. So I've ordered some pure nickel stuff. We'll see how that work. When I do get it to fire, it seems to only fire once so it may be some kind of connectivity issue. I've checked continuity on all the cable lengths and such.

[@ExtremeDIYGuy]

Not sure where to tell you to check next. Sounds like you're on the right track. Should fire once per trigger though so that sounds right unless I misunderstood.

[@josephmorado6854]

Can i use the starter relay of motorcycle for alternate

[@ExtremeDIYGuy]

That should work fine

[@jean-francoisdion2355]

Hi sir, how much did it actually cost you, approximatively? I am just wondering the advantage between your DIY spot welder and a 25$ spot welder on Amazon. Thank you!

[@ExtremeDIYGuy]

I think I spent about $40, but it was more fun to build than to buy!

[@johnconservative469]

I'm interested in finding the timer you used, and what the cost was. Please give me some advice.

[@ExtremeDIYGuy]

It's in the description but here's an affiliate link to it. amzn.to/3rnVBuu Thanks for watching.

[@RBH0909]

Did you use the timer controller that you linked to in the video or another one?

[@ExtremeDIYGuy]

I used the timer control that I linked to in the comments (it's in the video). That one gives you far greater control than the one I initially was going to use.

[@Hedge_ofthe_earth_fund]

@@ExtremeDIYGuy thanks!

[@dkarthik8946]

Hi sir can we use smps instead of battery, if possible how many amps smps to be used.

[@ExtremeDIYGuy]

I would be afraid to burn out the power supply. Welding does create a short across it.

[@PowerScissor]

Dumb question. Looking at the parts, I can't seem to source them for cheaper than buying a spot welder. I have to buy the parts anyway because I don't have them laying around. Am I looking in the wrong place? Or is this a more expensive DIY option, but performs better?

[@ExtremeDIYGuy]

You're probably looking at the Chinese ones that have recently come out. If all you are doing is a few batteries here and there, it's worth using one of them.

[@PowerScissor]

@@ExtremeDIYGuy Yes, the usual odd brand name ones. I know enough to not trust the reviews on Amazon, so figured I would ask someone who has some experience with them. I'm not building packs (maybe in the future), just usually single 18650 or rarely some series 2 cells for random projects around the house.

[@Jan-gj8bm]

Will this also work for 21700 cells?

[@ExtremeDIYGuy]

I don't see why it wouldn't. It should work for any light duty spot weld application.

[@scorpsec2605]

Great video, How did you make the spot pen?

[@ExtremeDIYGuy]

I have the footage for it, just need to find the time to put it together. Hopefully within the next few weeks.

[@ExtremeDIYGuy]

I have to apologize for that, I intended too but during one of my PC cleanups I accidentally deleted the original footage. I did describe it on the article on my website, extremediy.org/how-to-make-a-diy-spot-welder-for-lithium-ion-battery-packs/ so hopefully that may be helpful to you.

[@jesselowe5346]

Man trying to figure out that schematic was fuckin my brain up but this video helped immensely Guess that's why I'm an airplane mechanic and not an airplane electrician lmao

[@ExtremeDIYGuy]

I'm glad the video helped out. The schematic is not my greatest piece of artwork though. It's more of an electrical diagram than a schematic.

[@robertsingleton2364]

Hi mate could you say what the other timer was and was it a lot better 👍

[@ExtremeDIYGuy]

Here's a link to the first one I tried, amzn.to/3kcrEXW , I didn't like it, it was difficult to program and didn't give me the granularity I needed to get a good weld.

[@robertsingleton2364]

@@ExtremeDIYGuy thanks for getting back so soon have that link but what did you end up with so I don't make the same mistake

[@ExtremeDIYGuy]

@@robertsingleton2364 Got it, this is the one I used amzn.to/2S5277u

[@malcolmbarrettboatman]

I am looking for the individual wiring for this spot welder if some body can send me it many thanks Malcolm

[@ExtremeDIYGuy]

Malcolm, I do not have any more detailed drawing other than the one I provided a link too. It's a representation of the electrical connections but not the individual wiring sorry..

[@GET_CLIPPED638]

Your pronunciation of solenoid is quite funny

[@ExtremeDIYGuy]

Thanks

[@panzznine713]

Hi sir, just wondering if is it ok to nit put solenoid in the circuit, does it still work the same?

[@ExtremeDIYGuy]

No, you would probably burn out the circuit board

[@panzznine713]

@@ExtremeDIYGuy I see, ty for the Response sir ^_^, oh in my case, cuz i dont have that type of solenoid or any other car solenoid, i research some stuff about how solenoid works, can i try a 12v mechanical relay instead of a solenoid? i'll only run this whole schematics through a 12v 5amp motor battery ^_^

[@ExtremeDIYGuy]

That should work. The starter solenoid is nothing but a mechanical relay that is capable of high currents.

[@panzznine713]

@@ExtremeDIYGuy TY for the response again sir, i'll take note of that, hope it works ^_^, really need to work on my li ion battery on my solar set up

[@ExtremeDIYGuy]

@gery barnet I cant seem to find your original comment I received in email but here's what I would try. Solder the prong you are having difficulties with to a strip of nickel and then spot weld that to the battery. I think the reason you need longer dwell times is that I was using a car battery and the available amperage is much higher than your battery setup. Make sense?

[@gerybarnet5594]

Thank you sir for the prompt reply. I bought and am using a brand new car battery for this specific purpose. I don't think I provided correct clarification in my original post, that is, I use the car battery for the welding circuit and the dewalt battery only for the power input to the circuit board. So I'm at a loss as to why I have to use upward of 400 milliseconds to weld the nickel tabs. The space is very limited around the prong area but I am going to try your suggestion today as to first welding a piece of tab to the prong then the prong to the battery. Thanks so much for your advice.

[@gerybarnet5594]

Hi again Jose. You deserve a better clarification than I previously gave. I am using a Dewalt 18vdc battery as a power source for the circuit board (board can use anything between 5vdc and 30vdc). I am using the new 12 vdc car battery as the source of power for the spot welding circuit through the solenoid. Other than using separate power sources, my setup is exactly as in your video. Wish I could post a couple pics to illustrate what I have. In any event, I don't understand my problem with having to use 400 milliseconds to weld tabs to the batteries when you had such great welds with only 70 milliseconds. Today I am going to try your suggestion regarding using a piece of nickel with the battery prong tabs. I will let you know how it works. Thanks again for the outstanding idea and video.

[@ExtremeDIYGuy]

Try soldering the connector to the tab and then welding the tab to the battery if all welds doesn't work.

[@ExtremeDIYGuy]

I'm not sure why you need such a long dwell time. Perhaps, If not the amperage, it may be the space between the welding tips or the thickness of the nickel tabs.

[@gerybarnet5594]

Hello again my friend. I think I have found my problem with not being able to weld the prongs. The prongs are part of the assembly which is plugged in and out of the Dewalt power tools, thus they must be sturdy. I tried your idea but unfortunately didn't work. Now, to my suspicion of what may be wrong. I was giving the prongs I need to attach to the battery top a good cleaning and realized that they are not copper. They appear to be brass or something similar, which I would think would require a higher heat and small dwell time (thanks for that term). After noting that point, I upped my dwell time, in 200 millisecond increments, to 1800 milliseconds in an effort to spot weld the darn thing. The prongs got very warm but didn't even come close to being welded to the battery. I looked at some of the other Dewalt batteries I have on hand and it appears that Dewalt used a welding pen with tips about as large as bb pellet. Those tips penetrated about halfway thru the prongs during welding. Well, I'm not giving up. I will continue to look for a solution and will find one eventually. As it now stands, I can weld up the whole battery pack except for this one connected to the prongs. Thanks again for your help....greatly apprecaited. By the way, if/when I find a solution I'll let you know.

[@nobelarya2435]

Can i use adapter/power supply?

[@ExtremeDIYGuy]

Possibly, it depends on how much amperage it's capable of producing.

[@ericperry6550]

Flyback diode needed in this design?

[@ExtremeDIYGuy]

Nope, I did not use on in this build, although it would be interesting to see if one helps in any way. Were you thinking of using one to protect the battery?

[@ricardobino7410]

Taking a look at the price of all the components, isn't it better to just buy the spot welding module they sell in the chinese pages or ebay?

[@ExtremeDIYGuy]

In retrospect it probably is, assuming it actually works as advertised. But that takes all the fun out of it!

[@user-2uf2kr2c]

I think it would be easier if you put the switch on the welding pen ...

[@ExtremeDIYGuy]

That's a great idea!

[@travisd8229]

How many welds do you think you used this for when building your battery? I'm building a battery pack that will require a few thousand welds and was curious how that starter relay would hold up.

[@ExtremeDIYGuy]

I used it about 50 times for the battery pack I made. Not sure how it would hold up to 1000 welds but it's a car starter relay so is pretty rugged.

[@JCHaywire]

I built this (TWICE!) exactly according to the plans. Well, I THINK I did... because it'll give a satisfying click if I hold the spotweld electrodes on a NON-conductive (wood, plastic, etc) surface. But if I press it to nickel strip, metal, wire--anything conductive--it clicks as fast as it can recover until you cut power. Sounds like a ratchet Somewhere I did something fundamentally wrong. What would make it click repeatedly and not deliver power to the electrodes?

[@scrapper501r]

Figure this out? I'm having same issue. I feel like it has something to do with the second pin on the solenoid. He has a black wire going to somewhere on the controller. But I can't see where?

[@daviddowell7729]

your wiring doesn't match the schematic attached. i really wish you would've showed where the small wires being routed were going on the side terminal. i can get my trigger to wrk but the welding pen is not working for some reason. i can't tell what is what in the video but following the attached schematic isn't working.

[@ExtremeDIYGuy]

David, sorry. You're not the first to let me know that. This should help, there three key areas you want to make sure are grounded to the neg side of the battery. 1) the back bracket of the starter relay 2) One of the small terminals on the front of the relay 3) the second terminal down on the left side of the control board, 4) the bottom terminal on the left side of the control board. The schematic is an electrical representation but I think it is confusing. I'll try to work on one that shows every connection.

[@daviddowell7729]

@@ExtremeDIYGuy thank you so much for this. I will rework it today! also, I'm sorry if I came off rude. this is the best tutorial I've found and I think you have a real talent for DIY videos. I appreciate all your help and the time you have put into making this information accessible.

[@ExtremeDIYGuy]

@@daviddowell7729 No worries! I appreciate feedback, makes me keep my game up! I'm glad you find my videos helpful!

[@daviddowell7729]

what are you doing on the right side of the circuit board? i noticed on the instructions that came with it there is a "single power source" diagram but i cant tell from the video where they are being routed.

[@daviddowell7729]

@@ExtremeDIYGuy anytime man. i'm definitely a subscriber now lol.

[@chrisdaniels4674]

Mine only works on the first try

[@chrisdaniels4674]

Any ideas

[@ExtremeDIYGuy]

Not sure, i dont have fuse in the design, not sure if you do. Does the board power up?

[@silverfoxmetaldetecting7791]

The wiring you have in the video is wrong. Solenoid base is ground. I terminal on solenoid is not ground but direct short.

[@ExtremeDIYGuy]

Yes, that's why I have the main ground lead connected through the base of the solenoid.

[@joes973]

0.01s = 10ms = 1/100s 0.001s = 1ms = 1/1000s I think you mixed these up a bit in your commentary.

[@ExtremeDIYGuy]

I did and I should know better since I've been in IT for over 40 years!

[@joes973]

@@ExtremeDIYGuy Hah, I'm in IT too. I tried to make a similar welder to yours, but using a smaller battery, and it didn't work for welding 0.3mm copper strip. I'm trying to use some high amp 21700 cells and I want to access up to 30 amps per cell. Any ideas for what material to use to connect to the cells that will allow 30 amps through safely?

[@ExtremeDIYGuy]

@@joes973 It reall all depends on how many cells you have in the system. Most of these battery packs will connect a set of cells in series for the voltage you want and then connect those to another set in parallel to give you more current capability. Having said that, it's the bridge between the cells in parallel that would be carrying the the brunt of the current. You can spread that out by putting in a connection for each battery in the series in parallel to the battery in the series next to it. I wish there was a way to post a diagram because what I just said sounds confusing.

[@joes973]

@@ExtremeDIYGuy No, that makes a lot of sense. I've watched hours of videos on it. My problem is that I'm using high amp cells in a 12s2p battery, so I only have two terminals per connection.

[@ExtremeDIYGuy]

@@joes973 I would go with regular nickel strips and see what happens when you try it. Worse that can happen is that the strip acts like a fuse and burns open!

[@truthselectronics514]

This is called Assembly not make your own.

[@ExtremeDIYGuy]

Should I call the video Assembling the Assembly? It's all a matter of semantics.

[@gianfrancofronzi8368]

Why did you waist your money when you could have just used a battery and poked your welder for a millisecond?

[@ExtremeDIYGuy]

Mostly because I didn't want to blow up the lithium ion batteries. Secondly, because I thought it would be fun to do!

[@gianfrancofronzi8368]

@@ExtremeDIYGuy cool