Microwave Oven Transformer Spot Welder 2

Building a DIY spot welder from a Microwave Oven Transformer (MOT) - 2nd episode. In this episode I wind the low voltage high current secondary using some scrap CRT degaussing coils and I try to do some spot welds. Then I do some measurements and calculations and I discover that my spot welder could be optimized. In the next episode I will do some improvements and test it again.
The next episode:
• Microwave Oven Transfo...
The 1st episode:
• Microwave Oven Transfo...
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[@Elosocuriosobuscador]

-How much current do you want in the secondary? -Yes.

[@khayyam741]

I started loving graphs and tables after joining this channel.

[@michaelathens953]

This actually worked out better than I expected. I do love how unimpressed your cat was with that first weld lol...

[@rilosvideos877]

Cat is used to much more hefty experiments :-)

[@sortofsmarter]

your welding probes kinda look like little hands giving the sheet metal the middle finger...I love it..

[@jasonr9157]

diode gone wild has the most criminally undersubscribed channel on youtube, this guy deserves ten times the subscribers, i cant afford patreon for him but i do try and get others to subscribe, either through patreon or youtube, please do all you can to support this incredible content provider

[@WagTsX]

Oh my gosh, I've started to get worried about your vanish, specially because you've been working with MOTs. :)

[@jakubkolcar6789]

This guy has been working with MOTs since his childhood (truth) :)

[@DIYwithBatteries]

@@jakubkolcar6789 Since BIRTH. lol

[@omsingharjit]

@@jakubkolcar6789 😂😂 yup 👍👍

[@alex-r2pi]

I think the MOTs are less dangerous than the chinesium USB wall plugs he tested up to now.

[@mernok2001]

@@alex-r2pi Thats true.

[@JohnDuthie]

Ive been watching a ton of Photonicinduction and you upload this like a mindreader or something

[@samiulislamsharan]

Yeah, I've also been watching Pohotonicinduction a lot these days that guy is amazing. This channel is also full of fun and lot of educational videos and the cat as well. 😁

[@juntendo6104]

glad I became patreon and your alive!

[@DiodeGoneWild]

I had some trouble with my laptop. Finally I have a new one :). Much more powerful. I could even try to edit 4K or 1080p50 or 1080p60 on it. I may try it in the next video.

[@susceptibility_]

@@DiodeGoneWild 1080p60 would be epic! :)

[@DiodeGoneWild]

I'm more likely to use 1080p50 because in a 50Hz country, it's inherently flickerless, no matter the shutter speed. 1080p60 is only flickerless at some specific shutter speeds.

[@jugaduvlogger4998]

I edit my videos using my phone with the powerdirector app, and i made videos at 4k 60fps.. Love from India

[@Hardcorelactation]

@@DiodeGoneWild wat kind of laptop u got because i am looking for one

[@DuroLabs85]

That was a LONGGGGGGG time. Happy to see you back :)

[@hullinstruments]

Been looking for this video every day since the last one

[@drelectronics13]

Men I though lt u died of shock .was waiting from weeks for part 2.thanx god ur safe and alive😃

[@kemalkurt5257]

I'm happy to see you back Diode Gone Wild its been long time.

[@Speeder84XL]

Really nice! I was surpriced at first about the thick wire from an old TV (because there is no need to handle high currents in those) - then I got it, haha (it was actually one of the typical wide coils used for CRTs, that's cut up to get one turn of many parallel wires - smart idea). Also, well explained, how to get maximum power out from the transformer.

[@Edisson.]

Ahoj, díky, tohle je snad nejlepší video co kdy kdo natočil ohledně bodového sváření pomocí MOT 👍👍👍

[@droga_mleczna]

Ah yes, the universal thermal insulation: sandpaper. BTW would it be possible to use graphite electrodes from carbon-zinc batteries?

[@legominimovieproductions]

Graphite electrodes may be heat resistant to a good point but one) they produce damn bright arcs and second) the "high" resistance of the graphite limits the current too much

[@Basement-Science]

@@legominimovieproductions yeah with graphite electrodes you would get almost no current to flow at

[@SeanBZA]

@@Basement-Science Done welding with D cell carbon electrodes though, you can use them to join pretty thin material with an arc weld. Just use a pencil sharpener to make the point sharp, and the other end use some copper thin wall pipe lightly crimped to the carbon rod to make a lowish resistance connection. you might go through a few D cell carbons to get the crimp right, enough pressure for good current flow, but not so much it shatters.

[@Basement-Science]

@@SeanBZA Arc welding is very different from spot welding. There, the plasma arc heats the metal, but in a spot welder the current itself heats it. That's why you need a lot more current and less voltage to do it.

[@Ironarcer]

Tried arcing graphite at 5V, very little current flow. You need something like 30V but then at that level it doesn't spot weld anymore - it just melts the entire workpiece.

[@netman69]

I have a similar thing and I made a small timer to time the spot welds. Turning it off rather than just removing the electrodes is (allegedly) important to keep pressure on the welds after completing them. To switch the transformer I used a zero-cross switching SSR to stop it from blowing the fuse, not the cheapest solution but very easy.

[@ertyuiiknbvcx]

Remember that it is not good to breathe in the fumes from galvanized material. I did work as a factory mig/tig welder and it was adviced to use extra ventilation when doing that when repairing someone others construction fault that had gone into galvanzation already, things that was measured wrongly on the drawing board and had to be done again. The weld also wont stick as good when it is galvanzation or paint in between there so use a angle grinder and clean it up to bare metal before you weld and it will stick much better :) We also had a spot welder there and it had a foot switch like you mention, and it had replaceable copper rods as contact points to spot weld metal plates. Becourse copper wont stick to steel. Actually you can use a thicker copper plate and fill in with weld if you have a steel plate with a hole in it that needs to be filled, it will save half the grinding needed afterwards, yeah, this is for using a mig welder, not spotwelder. They learned me all kinds of techniques there. But just to give a understanding on how copper works when welding. Also the wire nozzle on a mig welder is made of copper beourse of that.

[@1pcfred]

Metal fume fever is kind of nasty. I've done it to myself a couple times. For days I feel like I have the flu. Just generally don't feel too good. I hear in really bad cases you can even die.

[@allthegearnoidea6752]

I have done quite a lot of spot welding and one of the most important part is the alignment of the electrodes and the clamping pressure. It’s a good project to build a home spot welder as they are expensive.

[@englishrupe01]

Just what i was going to say! Many people seem not to realize that clamping pressure is essential. You dont want ANY air-gap between the plates for the best weld. An excellent spot weld will pull a plug out from one side or the other.

[@jamesdavies686]

You can modify the eeprom of that current clamp to go up to 600A. I have the Uni-T version of it. I believe they are the same exact chipset.

[@nirajsomai9957]

Very Beautiful Video Sir. I learnt some next level stuff from the above video. Thanks alott sir for your work. Please keep uploading such videos

[@Miata822]

Fascinating. Thanks for posting.

[@ats89117]

Great video! I have never seen the loading effects on the transformer efficiency explained in this manner...

[@rastapaez3992]

I suppose I wasn't the only one worried about his silence. But now: NiiiiiiiCE

[@ovalwingnut]

I (who knows next to nothing!) have been buzzed pretty good on a 12Vdc car battery. I must have just got a REALLY good connection. It reminded me of getting a poor connection/zap from 110 line voltage. It was a good enough Buzz that I now treat those dang little acid-boxes with a little more respect :) On the other hand (pun).. you are the Magic Man and the original Count Voltar the Incredible and the hardware looks out for YOU. So dig that my friend!

[@DIYwithBatteries]

You've got cool stuff Dude 👍

[@UpcycleElectronics]

If you get the chance Danyk can you talk about possible over current protection used in retail welder circuits to avoid tripping the circuit breaker and maybe mention some rudimentary ways to deal with the transient spikes? I recently started messing with a U2010B based universal motor controller circuit and came across a dilemma that seems like your area of expertise. How can I calculate a transient suppression rc snubber for a universal motor when I do not have its specifications and my 50MHz scope is not fast enough (5ns) to monitor the spike? As far as I know the 100R/100nF default values are sufficient. If I can't see the spike it must not be there! Lol. The chip already failed once and I haven't discovered the culprit yet. I'd rather have a theoretically ideal RC value to use but I have no idea how to come up with the equivalent inductance of the motor to plug into: E=0.5 * L * I^2 ...to come up with the joules for the RC values.

[@AZ-vk7oe]

12:10 that is a very useful finding, that the maximum power is reached when the voltage drops to half. if the car battery drops to 6V when starting, then it simply cannot deliver any more power.

[@Pirelli.]

Very interesting. you explain everything so well and understandably !! keep experimenting, you can get even more out of that! thank you mr DGW! 😊

[@Basement-Science]

Maybe you could try to add some capacitors at the primary to improve the power factor when welding to reduce the chance of tripping the breaker? Not sure how much the inductive current actually is here, but it might help a little bit at least.

[@lasciencedelamusique6245]

You are the best my friend! :D :D Always fun time watching your experiments!

[@joejane9977]

lots of good fun thanks for the excellent explanation of impedance matching

[@RanaRao_Chandrachur]

Hey, your spot-welded leads are showing middle finger...Lol(on thumbnail)

[@wuukaa9079]

I put "some random solder on it" more like you "emptied your whole tin lol

[@plainedgedsaw1694]

I Guess it had to be done by blowtorch and acid flux.

[@wuukaa9079]

@@plainedgedsaw1694 hahaha yeah

[@anoimo9013]

very good analysis

[@blake301987]

Very good video, I learn so much from all your videos.

[@radekt.7843]

Thanks a lot. I'm working on my own spot welder

[@electronic7979]

Very helpful video. I liked it

[@pavelboucek9304]

Přepis do překladače pro lamy, jako jsem já ;) i may try to remove the magnetic shunts. Than the secondary voltage won't drop that much. But i can only do this in combination with less turns on the secondary, otherwise the primary current would be too high and it would trip my circuit breaker. less turns on the secondary means a higher ratio of the secondary current to the primary current. ideally, the secondary voltage shouldn't drop below 1/2 of the open circuit voltage. The voltage drops partially resistively (on the resistance of the primary and secondary), heating the windings, and partitially inductively (because of the magnetic shunts and the leakage inductance). But in both casses, the more the secondary voltage drops under the load, the less effeciently you're using the curent aviable from your circuit breaker.

[@jeffm2787]

It's becoming more difficult to find scrap wire of any quality these days. Modern devices certainly don't have any good wire anymore. It also feels like more and more stuff is using CCA vs pure copper these days. Ohh well.

[@NullPointer]

I like how many decimal places you use for the 0.666v measurement

[@VojaAntonic]

A nice project for brave makers, I like it!

[@prashantpisal2672]

Nice sir, Thanks for Graphical illustrating 🙏

[@LaLaLand.Germany]

I´d like to put together a spot welder to make 18650 cell batteries- I guess I don´t need 1200w. Just enough to spot weld nickel straps. Is it possible to control the power by the wire gauge used in secondary?

[@amkp40technology]

Your each videos really amazing ❤️❤️👍🏻👍🏻👍🏻

[@SzymekCRX]

5:32 Hey Diode, yo You know that this mains plug You're using is rated only for 16A, not 24A :D

[@SzymekCRX]

Correction, I think that even less, 10A :)

[@Gengh13]

It has a low duty cycle, so it should be OK, unless you are using it continuously.

[@mernok2001]

The circuit breaker of the socket is 16A.So it doesn't matter if you load it continously at 16A or at 24A until the circuit breaker trips,usually about a hour or slightly less.

[@Electronichub_05]

@@SzymekCRX I used one of these for a MOT and it started smoking after 10 seconds 🤣

[@imnotbeluga007]

The cable is flat, so it's even less (2,5A!)

[@tanishqbhaiji103]

Can you please make a video about your AC power measurement extension board as the commercial power meters are quite expensive here.

[@RobotN001]

9:40 u can take about 20 groups of wires , and put your current-meter into only one group , others groups will be shunt-like. multiply measurement x20 and result is ready !

[@zigge1989]

What would be an approximately correct size capacitor to correct power factor for a spot welder like this ?

[@kyoudaiken]

It actually makes it even more efficient as with AC the current only flows in the skin of the wire. Having multiple parallel isolated strands makes it possible for the current to flow on the surface of all conductors, leaving you with a lower impedance!

[@michamaecki8104]

Yes, but the skin effect depends on frequency. With mains transformer you would need (if i'm right) almost 10mm diameter wire (68mm2) to start seeing any difference.

[@kyoudaiken]

@@michamaecki8104 True, it's not switch mode.

[@Ironarcer]

I'm wondering if you could measure current somewhat accurately with a clampmeter if you just split the secondary output cable in parts and measure the current flowing through each part. (Then add the values together to get the total current flowing through the secondary.)

[@Ferraday]

then the flux crowding & fringing effects and you shit yourself

[@inductivelycoupledplasma6207]

Could maybe do that, but you'd need to match impedence carefully

[@coloradowilderness3139]

Learned many things specially Graphs .

[@bhamad12345]

Good job 💪

[@Killeroz]

Pěkně vysvětleno, díky :)

[@FixDaily]

4:58 Tips shape as like Mister Bean's greeting

[@laser-on-off]

As you already know, Koptan is a fake Kapton tape, and the characterictics are worse. It does not support high temperature like genuine Kapton and is dangerous. But it may be part of the show, of course.

[@Hellhound604]

Lets not get into Kapton tape. In the 80’s it was a huge issue in the avionics industry. It was discovered it outgassed in certain conditions, causing short-circuits in avionic equipment, and got banned. Spent months rewiring and re-insulating avionics wiring looms, ans learnt to hate Kapton tape. Nowadays, everybody is using Kapton tape again, even in avionics and aerospace. What happened, was it overreaction, or has something wlse changed?

[@WapTek123]

12:20 try many single "loop" secondaries in parallel , for more of the core filled for more cross sectional area & a lower resistance to match the weld resistance

[@alex-r2pi]

@DiodeGoneWild may I suggest a (maybe even DIY) Rogowski coil to measure the secondary current? Would love to see a video from _you_ on this topic - especially as it would fit nicely to this project.

[@rhiantaylor3446]

I like the idea of a degaussing coil as secondary, unfortunately this idea comes about 40 years too late for me as I no longer have any old CRT TVs to dismantle. Have to say I think it is the design and build of the arc contacts that really makes a good spot welder.

[@worroSfOretsevraH]

Try with electrodes on opposite side, but apart from each other. Thus forcing current trough both layers.

[@Tom-ro1qn]

How can we avoid the tripping breaker? Is it possible to put some condensators on the primary site? I have this problem

[@Tom-ro1qn]

​@@arletottens6349 thanks, It's definitely worth trying. I don't understand why not everyone has the same problem, we all use breakers in our homes, don't we?

[@Pulverrostmannen]

15:52 just look how much the windings vibrates in the transformer o__O bloodyyy heeeelllll

[@phxgen]

Damn I love this channel.

[@stevenbirch]

Great analysis

[@BobT36]

LOL I expected you to use some sort of fancy electrician's tool to remove the laquer. :D

[@godfather00cz]

starting 15:15 was like best ASMR ever!!!!

[@andrewhaychemistry]

Maybe use the solenoid for a car starter motor to switch current in the primary? That would take the load switching away from the plug.

[@Basement-Science]

Those are only rated for 12VDC switching. They likely wont last long at 230VAC

[@andrewhaychemistry]

@@Basement-Science A very good point, excuse my schoolboy error!

[@andrewhaychemistry]

What about a solid state relay instead? I'm not too familiar with their specs though.

[@Basement-Science]

@@andrewhaychemistry Any type of relay will work as long as it can switch at least 25A at 230Vac with at least a small inductive component. The relay coil should also be 230Vac to make the circuit simple.

[@andrewhaychemistry]

@@Basement-Science Great idea.

[@mynamemylastname2533]

Thank you

[@speekergeek]

You can pretty easily modify that meter to read up to 1,000 amps... There is a tutorial on KZbin and a forum called the EEV blog that has detailed instructions and multiple methods Edit: the instructions are for the UT 210E... Which is the same model that you have, only with a different name

[@douro20]

Polyimide films can handle VERY high temperatures. They also don't outgas so they are used in high vacuum chambers.

[@humanseagull2744]

Lol - more fireworks than ElectroBoom this week , nice bit of work on this one

[@MOJTABASHOMAL]

nice description ... i think the secendary windings on thins transformer can not effitiently demagnetize the primey windings that cuse the power factor on primery side cant reach near 1 at full load can you measure the input power factor and if it wasnt near 1 try a series capacitor on primery and also lower the ratio of the transformer

[@BRUXXUS]

That was bonkers! But also very informative. ☺️

[@williama29]

at 7:15 diode gone wild has a bad habit of tripping the breaker occasionally I mean I tripped a breaker with two heaters plugged in and it overloaded the breaker quickly

[@martinday2815]

Someone is using a screen shot of this transformer for adverts for energy saving.

[@adinko7]

I thought you are going to use it for Li on batteries

[@CodAv123]

Just seen an advertisement on eBay using the thumbnail of this specific video, selling a so-called "VoltBox" to save energy (probably because it kills you). I immediately knew where the image was from.

[@danielhorne6042]

im tempted to make one lol

[@jakub3851]

Prosím mohl bych vědět jestli je v čechách v každém bitě/domě třifáze. dekuji za odpověď kamarádi

[@Zloy_nub]

why don't you remove the shunts? maybe i'm getting something wrong, but those shunts "short circuit" the magnetic field and limit current on the secondary, so current draw on the primary side is unaffected btw, you're lucky if windings are actually made of copper, i think nowadays they made of aluminum mostly

[@CeZero4]

I think the best way to turn it on will be proper thyristor. Even then you can control welding power. Using similar circuit like these in drills or other power tools may be a good idea. Going further adding time counter you may finally produce professional device. Cheers G

[@inductivelycoupledplasma6207]

Variac would be better. That way the pri voltage can be reduced so the core doesn't saturate like crazy

[@augustus4711]

A very efficient way to remove the laquer from those wires is to dip them in a hot concentrated solution of sodium or potassium hydroxide. Very dangerouuuus, of course, but the cat would love it (watching it from a save distance, od course²).

[@kolinevans9127]

Great thanks for sharing

[@ricardomenzer]

Hey! Do you know that your build (and this video thumbnail) is being used as a click bait Google Ad for magic devices that can (supposedly) reduce the energy bill? About the advertiser Name UAB Commerce Core Location Lithuania I couldn't find a way to link to the Ad directly...

[@kookyflukes9749]

Have you ever tried lichtenberg effect on wood with a microwave transformer. I'd like to see you should do a video on it and it's safety implications.

[@flytrapjohn]

Bloody hell!

[@miklov]

I like the feline commentary!

[@1pcfred]

World's smartest cat!

[@jamessteele8181]

Hi, how about use 2 transformers?

[@puzzlefactorysoundstudios]

Use a solid-state relay with a footswitch and/or very short timer.

[@uksuperrascal]

Nice to see you joined Lbry and Odysee, See my reply on your odysee channel under your Community Icon

[@phxgen]

What is the brand or model of that rotary tool, if you don't mind?

[@phxgen]

Oh dang, and that clamp meter! Looks like it says AC & DC, but just 20A and 100A max? Does it perform well for lower current non contact DC Ampere metering? I have several but they are all 400, 600, 1000 and such. I live like right outside the sun's coronasphere currently, days with highs of 50°C or even slightly more have become common in the summer now, something like 120 days per year of highs at or over 40C, and this "winter" kinda forgot to happen so we had 20-30C days throughout most of Dec/Jan...I think we had _one_ dawn low of about 0C and just a few 10C lows. Naturally, TONS of people in my city use solar panel arrays. Storage devices like "powerwall" for peak rate hours use are VERY common as well, as eliminating or substantially mitigating grid mains use between 15:00 and 20:00 here can save mountains on power.* My ammeters are all high-end professional devices, but just adequate when, for instance, I'm just measuring several hundred DC amps load on panel arrays and such & don't need like +-1% accuracy or anything. A small DC noncontact clamp ammeter that's reasonably accurate for smaller DC loads would be SOOOO CONVENIENT for troubleshooting vehicle issues, smart home install, so so so much more. In over 20yrs of sparky work, I've literally never seen a clamp ammeter like that in any big box or specialty store, neither here in a city of population 5M or so nor my second home in a very large conurbation of 20-30M pop depending on who's counting, let alone a 20/100A clamp AC/DC ammeter! *off-peak seasonal range is about four to seven cents per kWh here, literally as little as 1/12 what I pay in California, while on-peak rate is the same PLUS like $17.50 per average kWhs used during peak hours each month. The peak surcharge might hit USD700 in the summer, _just for those 5hrs/daily, so panels & a charge to get you through those 5hrs can really pay off if you use a lot of juice, and I use a LOT of juice for a residence. 250VAC split-single phase 400amp service & four subpanels due to an odd L-shaped 3200sq.ft home with an additional ~800sq.ft of workshop/office and a second two car garage for garaging up to six vehicles, or more commonly just the nicest one or two alongside tons of huge powertools and various junk. Did I mention that it's perfectly legal for anyone to grow cannabis indoors here? :p

[@anmolkumar6704]

Would it be a nice idea to add a soft start circuit at the primary? Maybe the initial spikes will trip the breaker if you remove magnetic shunts?

[@physicsandmathemathicssimp833]

A switch is way easier .

[@windshield11]

An SCR with zero cross detection is perfect, somewhat costly for this current maybe? I'm certain he can find some communist switches that can handle the load ;)

[@ikehsamuelifeanyi4925]

Please Sir can you do video of old VCD Radio frequency (RF) module with circuit diagram.

[@Hobypyrocom]

you can use acetone or aspirin (acetylsalicylic acid) to remove the lacquer from such wires, its way easier than scraping it or burning it...

[@Delali]

Something plated copper got me laughing. 4:32 I guess sometimes it okay to not have all the answers.

[@MuhammadHanif-bx4pb]

do you have any tip for removing the enamel coat on those thing without sandpaper or scape it with scissor ? I tried to burn it but no luck :(

[@johnsmith7676]

Methyl ethyl ketone (MEK) should work.

[@physicsandmathemathicssimp833]

Just sandpaper the copper until it's shiny enough and then put lots of solder on it to connect the wires which have not been connected together yet .

[@Basement-Science]

The age old question, how to remove lacquer on wire... I'm yet to find a reliable method that removes ALL of it, no matter what diameter, enamel type and temperature rating, In my experience sandpaper works by far the best for medium diameter and up. Things that do NOT work, but are often suggested anyway: Acetone, burning it off, dipping it in a solder pot etc. @John Smith can you confirm if this actually works? To my knowledge MEK is very similar to Acetone, which as I said does not work.

[@MuhammadHanif-bx4pb]

@@Basement-Sciencethe problem is sanding 0.2mm individual wire from litz wire is pain in the butt :( Tried to dunk it in a pool of tin but no luck. well I guess the best method is still scrape the thing off the old way

[@Basement-Science]

​@@MuhammadHanif-bx4pb Of course, these are all bad options. I've had some success with using hydrochloric acid once, but need to do more testing. It seems to destroy the plastic faster than the copper.

[@alex-r2pi]

5:03 LOL solder melted and dripped due to high current tests?

[@LubckeEnjoyer]

Nice job!

[@petrbrazda1064]

Taková oáza dobré nálady. A ty kočkoviny. Občas se dívám a hledám: už něco nového od Diode?

[@MegaSunRise3]

Can you spot weld lithium batteries with this?

[@michaelfisher9671]

I do, with a spot welder of very similar construction

[@legominimovieproductions]

Just be careful not to heat the battery up for too long, having the bottom (negative) of an 18650 glowing like diodegonewild had the metal parts glowing would very likely result in an explosion and serious harms

[@physicsandmathemathicssimp833]

Of course , you could all though overheating the battery leads may lead to a risk of fire explosion and so on...

[@michaelfisher9671]

@@legominimovieproductions Sure but you don't need to. Dany was just playing around for effect. You can spotweld battery packs together in a few tenths of a second.

[@Basement-Science]

@@michaelfisher9671 You would probably want to use a timing circuit for it. Make sure it cannot run for more than a few ms.

[@andymouse]

Fascinating...cheers.