$20 PCB Spot Welder Showdown: Round 1

[@rclewis01]

it isn't just the 8 mosfets, it is the fact that the battery plugs straight into the board. It is amazing how much length and gauge of conductor makes on voltage sag, and therefore, current. If you take the weakest one and hook the negative directly to the battery and make the cables thicker, it should really perform fantastically.

[@stevenc22]

Have already done testing with bigger cables soldered directly to the board and the weaker spot welders didn't do much better. I think it is mainly down to the size of the pcb traces, the mosfets and the cable diameter.

[@losien1]

There is one problem with the “winner” board and maybe others too. You are missing the capacitor which may save the board or may not (my case) but the real deal is below. The whole thing blew up on the second spot weld in it’s life. This is a very common problem with them. You MUST use a very powerful battery but you never really know if your one is powerful enough until you try. If the sag on the battery during making a weld will go too low the voltage that drives mosfet’s gates drops and the whole thing gets damaged in nanoseconds. That’s why they keep saying in every description of that product to use a powerful battery. Anyway I have modified mine to avoid those problems in this way: I’m using a build in xt60 connector only to power up the electronics so i can use even a tiny 3s 1000mah battery. It doesn’t matter because this battery is not being involved directly in welding it just provides a sustainable voltage without any sag during a welding process. I have beefed up traces by using some copper cores from electrical cables on the bottom of the PCB. Also i’m using 5s 4500mah battery at storage level so i don’t need to discharge it afterwards orhetwise lipo left at 90-100% of charge would get damaged. So the positive from 5s lipo goes directly to the probe while negative goes thorugh the pcb. I’m using very thick car audio cables and 3mm dia copper sharpened tips. I have to use the lower power level (red) because welds are soo good- I haven’t even dared going on higher levels. They are tricky but if modified can be really good. There is one thing that annoys me a bit: although you can set the time from the short to the weld very often it happens randomly. Let’s say you set it at red level so 2 seconds and weld sometimes happens after 3,4 or 5 seconds.

[@AvengerIl]

Mine came with a capacitor but no instructions where to place it? Im using a 3s 4500mah battery and i have no time to 'fix' the circuit like you did.. hope it doesnt blow up on first try

[@casparv]

.15 is not 'the best stuff you can get'. You can easily get .20, which is what I prefer. And don't forget the difference between nickel plated and full nickel; the former is easier to weld but the latter carries higher currents.

[@stephenmaynard5408]

I would think putting a heat sink and small fan on the 8 mosfet unit might be a good plan. I get mine from AliExpress tomorrow ! I made one using a ford solenoid and motorcycle battery with a timer and button and homemade tips connected using 8AWG Stranded . It is too strong Timer wont go to short enough interval. May look into modifying timer board with a different cap to drop into millisecond range,

[@brookerobertson2951]

Looking forward to seeing round 2 ..

[@supercrazymario404]

Thanks for this video! I’ve been looking for a good spot welder and I saw the one with the 8 mosfets on eBay in addition to the other 2 which were cheaper so I’m glad that this one is gonna be worth the extra cost!

[@salvatorebarbaro5862]

The length of the cables to the battery affects the performance but it is not so fundamental. The most important thing is that the battery cannot instantly deliver the current required for welding in the short time that the mosfets are activated. An paralleled array of low ESR electrolytic capacitors, 2000 uF x each Amper of the battery, must be placed near the spot welder circuit and the battery. Then you will see that even the poorest spot welder will work much better. Another very important thing, those boards have the vias under the mosfets empty of tin, the tin serves to conduct the current and also to dissipate the heat of the Mosfets, so it is good to integrate tin to fill the vias under the mosfets and area of copper reaching the connectors.

[@MirceaTD]

Already put the winner in my wishlist

[@juanhernandez1238215]

I shared few videos of some other KZbinrs with their own ideas using this spot welders it’s pretty interesting and cool I think

[@abzaman77]

I'm guessing the reason why you blew the first spot welder because of the drive voltage. As it was designed to run with single cell lipo i guess they aren't using any seperate ldo or mosfet drivers to drive it. Thus 4s, 3s lipos can easily destroy the gates of the mosfet as they turn on. Also 3 of these mosfet are fine to drive over 400 amps as they are rated 300 amps (theoretical max) individually. So short burst shouldn't be a problem unless it's faulty or too much voltage sag from the power source.

[@pablosoto5407]

Hot of the needles from the model you like more can be produced due to more resistance of the needle assembly (cable plus needles) of this, compared to the other needles of the other models.

[@graham6411]

The number of MOSFETs is meaningless without knowing their specifications. One MOSFET of sufficient size would outperform any number of lower-spec MOSFETs.

[@gimmieliberty6514]

built a 10s9p pack with the first welder shown (95Ah 12v truck battery power source) and was initially impressed with the results, after a week whole strings where dead due to failed connections, if your not ripping nickel your not welding

[@stevenc22]

Agreed. Need to make sure you have good penetration with the welds. Also make sure you are using real nickel and not nickel coated steel.

[@helichuck1]

Do you think this will spot weld to the bottom of "O" Gauge train track?? Would be so much better than solder

[@stevenc22]

I don't know how thick train track is. These work well on thin nickel but quickly stop penetrating once the metal gets slightly thicker

[@juanhernandez1238215]

Good video , I knew the last spot welder would win , I had ordered the first two spot welder that u tested at firs and the only way u may get them to work ok only , it’s by using a large capacity car battery , they useless with a lipo battery but the last spot welder with 8 musfets it’s pretty good , I use the last spot welder with only a small 1500 mah 120c lipo battery and it kick ass pretty good , just to give u a tiny tip if u buy any lipo batteries try to buy the ones that have the higher amount of amperage discharge like 80 c and up , if u used it like I said u will have better results

[@stevenc22]

My lipo is 80c. Yeah that last spot welder is pretty bad ass. I'm interested to see if some of the other ones I have on order are any better.

[@genesisvillaveza6765]

The PCB traces and lenght of wire makes the difference.. the mosfets act only as a switch

[@AvengerIl]

Why does the 3rd one come with a capacitor? the ebay pictures of the seller have the capacitor pictured, half the pictures its not even connected, just placed there for no reason...

[@barakcobrama1703]

bought the smallest one put it to my car battery and its great.

[@bobravenscraft5376]

Advantage to car battery 14 v. W polymer 12. Not difficult

[@littlehiawatha4870]

Very helpful, informative video. Are you able to tell me the IC number of the chip between R5 and D1 just above the switch on the first tested Smart battery welder. I bought one blown 4056 and this other chip. Thank you.

[@gopronomad4381]

It was blown up because you connected it to a battery that was never intended for the circuitry... Also the first circuit tho inherently more dangerous, modders can easily put them inside a case for safety

[@MrINKOMPATIBEL]

The winner of the test: Mosfets will blow up sooner (weak battery) or later. You can solve that problem using a power source for welding (LiPo) AND a constant 12-16 Volts for the board.

[@stevenc22]

Yup I did that in a later video

[@E-BikingAdventures]

3 volts? Lipo cells are 3.7v nominal.

[@B4nan0n]

I had a really weird problem with my spot welder, I hope you can help me to understand. I have the same you tested first ( the one you soldier at the end) after using it for 30 minutes I noticed the cables from the needles and for the battery were pretty hot. But was working ok. Very well acto at level 4. So just for safety I decided to use thicker copper wires for the needles and from the battery. I connected everything and was ON the welder with the green light, in first gear the weak one for like nickel of 0.1 maybe (Is 5 in total). I tested it and the mosfets exploded, like 2 or 3 of them. So I wasn’t using a different battery just bigger cables, can someone explain what happened please? Everything was in the right position I checked the polarity and the voltage of cables and batteries. Thank you so much!

[@stevenc22]

By increasing the wire size you might have drawn to much current which caused the battery voltage to drop too low to where the circuitry couldn't close the mosfets which blew out the mosfets. This is a know issue. Battery voltage sags during the weld and if it gets too low the mosfets won't close. I did a video where I converted the circuitry to run on a wall plug instead of the battery so the circuitry wobt be affected by the weld.

[@B4nan0n]

@@stevenc22 ohhh… I understand. I thought was related to have too many amps because the thin wire is not a limitation now. I will try to find your wall plug video. Thank you so much for replying.

[@vivekkapoor]

The video is kzbin.info/www/bejne/jJjKiYiOmq2ngqs

[@samohraje2433]

The best option for the portable spotwelder is to use splitter from 1 Xt60 to two xt60's. The cable dia should not be greater then 10G, otherwise you could potentially blow the PCB right in to the space. The problems are graduating when you modify something e.g you start with 10G wires, the pcb traces are too weak to handle that much current so you add a bit of solder to that traces and another problem occurs, the mosfets are basically rated at 250A peak short circuit, when you combine 4 of them, that's in fact 1000A but in reallity is not as much as 500A amps shorted... even the fake ones has basically same specs... the only PCB that could handle that much current is BIFRC with 8 mosfets but i rather than solder, i will use nothing just leave it like it is with no modifications. Let's talk about this splitter. Why? Because when you use two 3s lipo batteries ( 5500mAh with highest C rating ), the voltage sag should not be that high( or low ). You need to pay really extra attention if you are affraid blowing this and buying another one.

[@customcutter100]

Which "needles" were you using on the BIFRC? 10ga or original 12ga? Have you tried welding with the BIFRC at a lower setting that is comparable to the 4 Mosfet results and been able to weld without overheating? Thanks for this series of video, looking to upgrade my spot welder that is a battery, 12v solenoid, and button. LOL thanks, again.

[@ed-jf3xh]

MAybe the neg side is thinner?

[@bergi85]

Do you have a link for that lipo battery you are using. I was on Zeee's site and I don't see an 80C 11.1V battery, I only see a 50C 11.1V battery. Or some 80C with much lower voltage.

[@stevenc22]

www.amazon.com/dp/B08162YBVF/ref=cm_sw_r_cp_apa_fabc_h4PZFb09ZR64W?_encoding=UTF8&psc=1

[@bergi85]

@@stevenc22 thanks!!

[@TC-hl1ws]

@@stevenc22 Thank you

[@GeertDroid]

The link does not work anymore. Can you give us the specs of this LiPo ? Brand: Zeee Cells: 3S Capacity: 5200 mAh Discharge rate 'C': ?

[@stevenc22]

@@GeertDroid 80c

[@j.d.3269]

With a more powerful battery, the first two can perform as good as the third one with a weaker battery.

[@alvinanacleto6588]

oh my,i. maybe late enough to see this video of yours,just bought that smart welder,and it doesn't work at all😔

[@stevenc22]

Unfortunately half the welders I bought were crap. There are only 2 I really like and use daily.

[@Nghlong203]

For mosfet 4N04R8 Vgs max = 4V

[@johnreyfrancisco4373]

Sir can i use 12v 60A battery pack to the winner spot welding pcb? Sorry for my grammar im not good in english

[@stevenc22]

No. That is not enough amps. My lipo is 12v 400 amps

[@johnreyfrancisco4373]

@@stevenc22 thank you sir

[@appk5884]

You can use a car battery with 350 to 400CCA (cold cranking amps). I used a 12v 35ah 350CCA with one of these pcb and it did a decent weld.

[@johnreyfrancisco4373]

@@appk5884 thank you sir

[@ImaginaPower]

next time charge up your lipo first . I have the same spot welder with a car battery and the smaller "needles" and the weld will tear when you pry it off

[@frodemolland6249]

Hi, is it Possible to use car Battery instead of that lipo Battery? I dont have either of lipo Battery or Charger and both very expensive where I live

[@stevenc22]

Yes you can. I also about to test a new spot welder that has a built in battery and only costs $28

[@xwatchid]

The lead battery must be good nonetheless. Check if the inner resistance is good enough, there's also a range to consider.

[@richardjelinek5038]

How about putting some heatsink on the winner board?

[@stevenc22]

Yup I did. In a later video I mounted mosfet heat sinks to the board. It's awesome

[@Za_TA]

What you think or say. So I dint know about mosfet/diods/resistor , but if mosfets burns, what if instead of OEM 5 in row, and another row of 3-5? will it stop exploding?

[@stevenc22]

All the mosfets are running in parallel. A second row won't make a difference, just the total number of mosfets and the thickness of the pcb traces.

[@Martinko_Pcik]

Can you place the board that is heating up to the glass of vegetable oil to help to cool it down to work non-stop ?

[@inoahmann7542]

Yep, but the you've got oil everywhere, lol. It would work though.

[@yudhiaaron3725]

What the recomended power input for spot welder like that? Can i use psu 12V 40A? Or i should use car battery?

[@stevenc22]

Minimum is 12v 150amps

[@stevenc22]

But really 250+ amps is needed for a good spot weld

[@yudhiaaron3725]

Whaaatttt?? 250Amps????? What kinds of psu should i use??😂

[@stevenc22]

@@yudhiaaron3725 lipo battery or car battery

[@yudhiaaron3725]

Ummm... Car battery ussualy have 40 Amps - 65 Amps. But you say 250amps right??? So... Its mah or ah?? Because what i know 1Amp = 1000 Mah. Correct me if i'm wrong.

[@vick_garage]

Can you show me battery recomended lipo or li ion?? And recomended C 45 or 50C?

[@stevenc22]

80C battery i use amzn.to/3cOIADl

[@stevenc22]

This is my other battery. a 50c lipo amzn.to/3wp8DLk

I have the same, but it did not weld well with the 12 volt 90 ah battery, where can the problem be?

[@stevenc22]

Im welding with a 400a battery

[@jiannisgrigoriadis]

Hi friend if you still have this I need your help. I have the same and T1 component burned .....can you tell me what it is? send me aphot or read it? the first on the right. The most common one

[@stevenc22]

I do not have the one on right anymore.

[@jiannisgrigoriadis]

@@stevenc22 Thank you anyway.

[@Jo-hannson]

thank you sir

[@ImaginaPower]

forgot to mention that I have soldered on the traces to thicken them.

[@sarhangsaeed7341]

Who's the winner ? Which one is the best ?

[@stevenc22]

www.ebay.com/itm/12V-18650-Battery-Energy-Spot-Welder-PCB-Circuit-Board-DIY-Auto-Spot-Welding-Pen-/264585775348

[@stevenc22]

This one by a mile

[@sarhangsaeed7341]

@@stevenc22 thanks Bro

[@solarskillsvision734]

Please can I use lipo battery 14volt with bifr spot welder

[@stevenc22]

Fully charged a 4s lipo hits 16v. That might be too high!

[@solarskillsvision734]

What about lifepot that charged to 14volt

[@solarskillsvision734]

I mean lifepo4 prolismatic cell battery 3.2volt * 4 it charged not more that 14.4 can that work

[@stevenc22]

@@solarskillsvision734 14.4v will be fine. A lead acid battery can get to 14v.

[@rcari0687]

Can i use a 12v 18650, 3s2p or 3s3p, to power the spot welder?

[@stevenc22]

No it needs 300+ amps. You can use a 3s lipo

[@Boz1211111]

You could, vtc5a has high pulse current ratings

[@GeertDroid]

You can not use 18650's as a feeding source for any spotwelder. They just have no juice enough to feed such high current and you will blow the mosfets for sure. Mabe in combination with supercapacitors it will work.

[@sunuk1915]

Do you measure which amps there?

[@stevenc22]

No. Would need a meter capable of measuring 400 amps and storing the reading because the amp flow will only be for a split second

[@أبوبكرأحمد-ح1ع]

hi .Please, I have the same product on the right, and I have no problem. Never weld, is it poor manufacturing or what How can I contact you? Thank you

[@stevenc22]

It does or does not work???

[@أبوبكرأحمد-ح1ع]

@@stevenc22 Doesn't work there is a pulse but not welding

[@stevenc22]

what battery are you using? I'm using a 400amp battery.

[@أبوبكرأحمد-ح1ع]

@@stevenc22 60 ampere battery Is it necessary to use a higher ampere battery? What is the lowest value can be used?

[@stevenc22]

150 is the minimum. But really higher is better. Just get a cheap lipo 3s 5200mah 50c+ for $20 or try a car battery. www.amazon.com/dp/B07ZV73D5S/ref=cm_sw_r_cp_apa_fabc_DQC1VTF74JMJFG9CHJ7Z?_encoding=UTF8&psc=1

[@joeshmoe5177]

Why did you have to kapton tape the winner but not the others?

[@stevenc22]

Just to protect against accidently short circuit. There are lots of traces on the bottom and if you accidently set it down on Nickle you could short circuit everything. It's on the winner because I have used the winner to build multiple ebike batteries.

[@joeshmoe5177]

Thanks so much for reply! Just soldered mine together now and let’s hope it doesn’t blow! 😁

[@joeshmoe5177]

Ok so good news - it works! Bad news - even on red it blew a hold through my strips test... I am using a 600 CCA deep cycle battery. Do I need to use a lower CCA battery? Also is handling the board a shock hazard to me or is the tape mostly a protection against shorting the board?

[@stevenc22]

@@joeshmoe5177 cannot be shocked below 40v

[@stevenc22]

You can use thinner cable to reduce the amp flow if it's too strong

[@sleonard2649]

I'm mystified. I bought the BIFRC spot welder (shipped from China) and soldered the capacitor and leads as directed. Used a 1500mAH 100C 3S LiPo battery. The Supplier recommends 150amps or higher discharge battery. My Mosfets caught on fire the first time I tried to spot weld on the lowest setting. Did I do something wrong or did I just receive a bogus PCB?

[@stevenc22]

Could be a bogus PCB. Did it actually have the BIFRC logo and were all the traces gold? I've seen knock off's out there. Most likely just a bad board. I've had my fair share of bad boards as I did all the testing of the different PCBs

[@vang9416]

Steven, great video series, Thank you. I noticed that your BIFRC board does not have a 1000uF capacitor. I ordered the same BIFRC board with battery XT60 connector, did your board not come with a loose capacitor or did you choose not to use it or is it on the board and I just can not see it in the video? Thank you much.

[@stevenc22]

@@vang9416 correct I do not have a capacitor. Mine did not come with one. Looks like the manufacturer is now including one which is supposed to help prolong the love of the mosfets

[@shamarkateer7763]

👍👍👍👍

[@yourtubernoob]

Jesus christ dude, learn how to actually use the damn thing before you attempt to even remotely review it in a logical manner and environment... you drove me nuts holding down the damn button to get it into "Red mode" 😂😂😂 first off it has 5 levels, and second of all you simply press the button to advance through the different strengths of welding current...and if you'd realize how it actually works you'd also come to realize that it offers the best price to performance and build quality. I've used mine for the last 10 months without a simple hiccup and with strong ass welds at that... so maybe you will figure this out someday, who knows.. but I do know that the second round video won't be any worth watching 🤣🤣🤣

[@AmigaWolf]

19:57 "I can't take realistically have tp take a break every two minutes" Simple, put a heatsink on the MOSFETS.

[@Graeme758]

And this will keep the pens cool, right?

[@AmigaWolf]

@@Graeme758 I thought he was talking about the MOSFETS?