Cheap 18650 Spot Welder Reliability Mods and Test
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- เผยแพร่เมื่อ 28 ธ.ค. 2020
- These little 18650 spot welders can be found at several online retailers. Here are a couple of affiliate links if you want to help the channel:
► Amazon 18650 Spot Welder Better Option amzn.to/3mMv3Uy
► Amazon 18650 Spot Welder Original amzn.to/3NiR1J7
► Nickel Strips amzn.to/3o4QWtn
► Banggood 18650 Spot Welder www.banggood.com/custlink/3Dv...
The main issue seems centered on using batteries that sag under load. I've watched dozens of TH-cam videos where the user connected the spot welder to some form of 12v battery and while attempting spot welds, the mosfets pop. The testing I've seen indicates they pop because of voltage drop across the control circuit causing the fets to not saturate during the duty cycle leading to failure. We saw something similar to this with the ESC testing I did not too long ago. The use of a capacitor between the diode and ground of the control circuit helps minimize voltage drop across the control circuit and allegedly prevents damage.
Here is a link to the reference video I found showing the issue and the solution:
• Mini Spot Welder - wat...
The remaining mods: Reflowing solder on the negative trace, shortening the input leads, and connecting the positive welding pen to the positive input terminal are a combination of my own assessment, videos I've watched, and comments I've read about what happens when these fail.
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AFFILIATE LINKS
► Amazon Affiliate: amzn.to/3lEz5ZL
► Banggood Affiliate: www.banggood.com/custlink/3DD...
#RCVideoReviews #opentx - วิทยาศาสตร์และเทคโนโลยี
Well, it's almost a year later. I bought a $15 spot welder off ebay, and it turned out to be the same model you and Maker Fabio used, so the capacitor fix was the same. Whew. I used a stronger battery 3S 5AH 50C, and I could weld .15mm strips at the 35 setting. I just finished a 13S_3P pack with .15mm 5mm wide strips and it probably needed 600 welds because multiple layers were needed. When the probes got hot, I stopped to let things cool. I'm sure those Mosfets are seeing a hard life, but it lasted for one battery. I even ordered a second unit for a spare.
I appreciate your video. Also many kudos to Maker Fabio for his analysis.
Happy flying! I'm an ebiker and these RC Lipo packs still scare me, but I'm impressed with the balance chargers. I've got the RC battery safely stored in an old BBQ grill outside when it's not being used to weld. I watch it like a hawk when charging too, I never let my ebikes charge overnight either.
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I really like these types of videos that help others through research and testing. Thanks mate!
You're welcome.
Excellent timing on this video. I was about to pull the trigger on ordering it. Watched a bunch of vids on it. And only one mentioned the low voltage issue. And he didn't offer any solutions or mods like your video. Happy flying. 🤓
I just finished up my first 3s2p pack and it did fine using my 3s2200 packs as input source. It does like the higher voltage though +12v and I wound up using 45e on the batteries themselves.
Thanks for showing this!! I thought it had to be a big expensive machine. This is definitely an extremely affordable entry into proper manufacture of battery packs.
Glad it was helpful!
Bought this unit 6 months ago n made the mods but instead of wasting solder i stripped some ac copper wires n added to the connections. Man this litte unit works great for the price n i really like how compact it is, saves alot of space! Liked ur vids. Btw for those buying li-on batteries make sure u check the discharged current of the battery. I rushed my buying and ordered the wrong c rating! (5amp) cant fly most planes with that.
Good tip. Thanks for the comment.
don't hold the contacts vertically, hold them 45 deg to the surface and they'll work even at 20
I bought this spot welder a few months ago and did all the same mods as you right off the bat, including rounding the ends of the electrodes. It works perfectly and still going strong. Built a 4S2P for a portable power supply just yesterday. Absolutely hassle free.
I'm using a truck battery but like the idea of using a Lipo as it's small and convenient. Nice video.
That little lipo does well powering the welder. Mine is still going strong too. Appreciate the feedback.
@@RCVideoReviews My friend builds and flys drones, so I'm going to steal one of his Lipo packs and try it. ;)
@@RCVideoReviews cant find that turnigy battery 35- 70 discharge any suggestions on an alternative lipo rc battery?
I was Leary of this unit but now I feel more confident. Thank you.
Me too. I took a punt on this one. I've been thinking of a 4s2p 7000mah for the AR Wing too. ZOHD sells that for $89. I can make it for about $45. This tool would be very handy for that.
Thanks for sharing.
John.. I would prepare the tips of the probes to a rounded pencil point so the weld is more concentrated.
I liked the bloopers at the end...LOL
Thanks for the tips! Glad you found the bloopers ;)
Just now finding this video- thanks for the test/demo and the input for the fixes- Im teaching at a college that throws stuff away and if I can "fix it" it stays in use! Appreciate your content!
Awesome! Glad to help. Thanks for watching.
@@RCVideoReviews Mind if I give you an email about cells? wanted to see if the longevity of this device is worth it.
Thank you. Loved the capacitor addition, great MOSFET protection. Liked your over soldering very much. Saw this welder in other videos demonstrating the minimum amount of pressure that gets the strips to touch together works best. Also placing the contacts at an angel not straight up & down works well. Finally don’t create perfectly perpendicular welds, they’re not as strong. For whatever it’s worth. Thanks again.
Have been using mine for over two years now, Powered off a 3S RC Hobby Lipo. 5AH, 70-130C.
Great video, nice presentation!
Edit.
I bought one like this, it arrived yesterday. I took it apart to connect the capacitor and I noticed that the power copper lines on the pcb board are reinforced. The is a brass rod welded both on the (+) and the MOSFET side.
Thanks for watching
Yeah, i noticed the same thing, the manufacturer must have actually improved their product!
Thank you for your videos!
I made a charge station using your design with a couple of iSDT chargers and cut out some 1/4 inch plexiglass on the water jet and covered it with carbon fiber vinyl instead of using wood and I added some LED lights
WOW! Nice, I bet that looks fantastic.
Where's the link to that video?
@@drecoracing it was on Facebook
Cool idea with the capacitor! I managed to seemingly short the MOSFETs on my board. It's not the one you have but a black PCB that has a pushbutton, LED, buzzer, and control circuit with 5 MOSFETs. The MOSFETs now read a resistance of 12kohm between drain and source. Not great, but I hope to get an external 12v power supply connected to the next board I ordered to prevent this issue. I feel that the control circuit should be independent given how much current the MOSFETs draw. That would feel like a better solution in my opinion.
Many thanks for putting the link to my video, it helped a lot on the views and subscriber in my small channel.
Thanks figuring out the problem and sharing the fix. Glad the link helped you out.
i bought an identical kit and all these mods have been made to my unit prior to purchase. large bars soldered where you added more solder and a cap on the control circut
Maybe they watched my video. How has it been working for you?
Informative video👍 Please can you tell me the specification of capacitor used? Is that 50V/1000mf ? Thanks.
It has been said that if you round-off the electrodes just "slightly" and hold them at 45 degrees to the surface you're welding, you get Much Better welds (less area getting the "Juice", and deeper penetration of weld!).
(NOTE: I haven't tried that method yet, but have witnessed it on a Friend's set-up. He uses a motorcycle battery for a power source.).
Thanks for all the information about where to "tie-in" the positive lead, and "reinforcing the elec. contact at the bottom of the board.
Great video!! I got the same spot welder a couple weeks ago. I did the cap mod before I ever tried to use the welder. I was trying to use a couple 35Ah batteries but had intermittent results. I have a 5200mah 50c battery ordered and should be here tomorrow. Maybe a little to big now that I think about it because thats 260A potential.
Im hoping I get better results with it.
I thought the traces looked weak. after watching this Im going to build up the negative trace and connect the positive directly.
I just finished a 3s2p pack using my 3s2200 and I did stop once to top it off. Other than that, everything worked perfectly.
My 5200 50c battery came in. I did end up completely desoldering the positive screw terminal so that negative wielding lead cant rub on it. So now connecting positive welding lead can only be connected your way.
I also used XT90’s for connecting power to the welder.
Im thinking about trying XT90’s on the welding leads just to see if there would be to much loss through the connector. I figure if it works ok thatd be nice because that would keep the leads together. As well as itd fit a little nicer in the 2.5” zipper hard drive case I stow it in.
I also took a micro push button mounted to a pcb I ground down to almost the width of wielding lead, soldered a 22awg silicone zip-wire to pcb switch and covered switch and pcb with double walled shrink tube with a hole just big enough for the center of the button to be exposed. On the other end I soldered the barrel connector that came with the welder. Then zip-tied switch assembly to welding lead similar to a tig torch switch is mounted. This mod/ add on with the spot welder set to manual mode makes this so much easier to use this spot welder and when I was using the auto mode, because you can position both leads exactly where you need them and get good pressure on both leads without rushing. The other nice thing about manual mode is even if you hold the button it will only trigger once. Unlike auto mode where it triggers every 5sec or so if you hold leads on welding surface very long.
So now with the battery and mod combo Im able to spot weld 0.23mm~0.25mm nickel strips used in Milwaukee battery packs. Ive successfully rebuild 4 packs now utilizing the factory pack strips.
I have 0.15mm nickel strip and I know could have been cut factory 0.25 of short welded 0.15 to that but I really didn’t like the idea of that many potential points of failure.
I find it interesting that with just a few mods that seem like if they implemented them in the manufacturing (at least in theory) would cut production cost and almost double its spec’d capacity.
I think they know exactly what they're doing. imo
@@jasonscorned Who’s “they”?
Hey great video i got me one of this welder and i think mine came defective cause its not doing the beep sound that urs make and also it send a powerful current pulse that make a hole on the nickel strip and there is no way for me to adjust it. thank u for the video. Ok i did write the fits couple of sentences with out watching the entire video and im going to follow the steps u did to see if i can get a lower current zap to the strip of nickel then from there i go again thank u.
Definitely need the capacitor. I have one and blew a bunch of mosfets as mentioned. They actually got so hot they welded to the copper so I damaged it getting them off (the ones which hadn't blown came off clean). I'm going to put some copper foil down so I have good contacts.
Great video! I bought the spot welder on your affiliate link. Got a great discount too, only 20 bucks! Cheers :)
Thanks for the note.
“Sweet Loraine” Great In intro. You’re listening to Kenny Baron.
Your video is great also!
I ve just bought one of these and not sure if it's faulty. Another video had it connected to a 12 v 7ah battery. That's what I'm using and it doesn't stick to the cells or even the strip. Was told to use a lipo so is that the problem. Yours welds at 30 mine doesn't at 99? Ps hasn't smoked or blown anything
Thanks for showing mods !
Thanks for this video ya just gave me the confidence to make my own 18650 packs awesome!
Go for it!
If you are looking to make high capacity packs for cheap, couldn't recommend 'second hand, lightly used' batteries enough. places like batteryhookup and jag35 have packs from different industries with little use that let you rip the 18650s out, paying very little per WHr compared to brand-new cells. For example, Jag35 has some scooter packs for sale right now containing 40 NCR18650BD cells (3200mAh, 10A) for just under $60 (~$1.5 a cell). Packs are around 95% capacity, making them great to repurpose or pull cells from. I have now 4 of those packs, two put directly to use in an EBike scenario, and other two harvest cells for EBoard pack building. Those two places sometimes have amazing deals that are hard to pass up. Recommend you look into them.
Thanks for the tip! Awesome info.
Fantastic idea with those scooter packs! I scored a ryobi battery pack for the outdoor lawn tools line, i believe it is ~30v... cost me like $7 on clearance at the end of last summer - I plan to gut it and take out all the 18650's and do the same!
Where do you guys all get this version of the welder... Mine has no diode or connector I might be able to solder the capacitor in. I have a bag of 1000micro Caps here and thought this will be a quick fix.... Until I found out I have a different solder version.
But good video anyways!
Ive done minor solder work. Which cap do i buy and which direction do i solder the cap? And can u show a pic of exactly where to install? Thanks. I understand if ur busy.
Where can you buy those batteries for that cheap? What’s the amp hour rating?
It is okay to soldering battery, just don't apply heat too long, and use right flux to make the solder stick quickly. But the problem is solder create bump on battery that make it not fit later in the casing or whatever you use. Spot welder not create bump, it just flat, and neat. But, they also not really cheap to have, if you counted it with battery pack you going to use. Even though this kind of portable spot welder are cheap, but you also need to buy a powerful battery to run it. You can't use a weak battery to do spot welding. Powerful battery for example lipo with 6000mAh, 50C rating is quite expensive tho.
Hi John, I think it was a later video I watched of yours using a spot welder with 18650 etc. Just one question, how are nikel strips rated for the ampage. I have looked, but with little success please
There's a chart out there with different amperage ratings for different metal strips. Search for that and you'll get an idea of what you'll need to do for different metals.
Thanks for giving a HELPFUL video that will save me a lot of time and hassle factor and probably money. You gave a solid technical CAUSE and FIX video to make this P.O.S. worth something!!!
Can you believe they are handing out surface mount FET's people will NOT be able to replace, rather than fix their damn crap engineering? Wow. What a nutty way to go.
I watched another video with zero info on this same device, and the guy never said a word, you don't even know if the video had a point to it.
As an Electrical Engineer, I can FULLY appreciate your mods, and the not saturating the gates of the FETS. Of course the FET resistance will be too high if not saturated!! Can you please tell me what the main (Green) cap voltage and capacitance is so, I can order both the Mod Cap, you put in, and the main output pulse cap from Digikey, and get Low ESR (FM Series) caps. Now I can feel confident ordering this, rather than paying $60 for the high failure rate one on Amazon I was going to gamble on. Thanks for your info! (I think we have commented on Aerostuff's channel with each other.) Oh BTW, are those Li-Ion batteries you are using? if so, where do you get yours? I'm currently making Aerostuff's Silver Eagle V-Tail Pusher for long distance flying.
The original video has the specs:
All you need is a 1000uF 16V(or higher) capacitor
I replace the 5 broken MOS with 4 superpowerfull Infineon MOSFET:
IRL40SC228CT 0,5mOhm 1440A pulsed
Yes, The design is definitely questionable when they send you spare FETs...
@@RCVideoReviews Right, I caught the values for the modification cap, I was hoping you could give me the values on the storage (green) cap that comes on the board. I want to make both of those caps low ESR for long life, and extra punch on the welds. I want to place just one order for the FET's and both caps. You know I can't use it until the modification (repair) cap is installed, and I want to do all the work at once before I put it in a case.
How does one attach a pedal for manual activation? Which pedal? Most pedals don't have the correct plug and a plug comes with the model but I don't know what to do with it. I think results would be better with a pedal as you would have the time you need to press down hard where you need to.
You don't want much pressure. Just enough for the surfaces to contact, but you do want some resistance between the surfaces in order to make the heat right there. Lighten up and it'll probably be fine down to setting 15 or so.
And thanks for the tips.
If i am setting on 15 and i am not pressing enough, i am becoming sparks
Been looking for one of these.
There are a lot of options out there. I picked this one because there were enough videos showing it to work when the flaws are addressed. So far so good.
I'm using this spotwelder with the cap Mod after one Mosfet has blown up. Now its fine. By Using supercaps i Was getting about 830Amps welding current.
Even withe long leads on the input side.
Good to know. Thanks for the info. How did you measure 830a?
@@RCVideoReviews by using a Big brass shunt resistor and a Oszilloskope
The unit I purchased looked the same but the circuit was different so I couldn't find where to add the capacitor. I did not add extra solder onto the negative side. I tested it first using a Car Jumping Battery Bank and everything worked perfectly but the car jumping battery bank had to be physically disconnected before it would reset for another weld. I then tried using a 12V car battery with the power set to 40 for a 0.12mm strip. One of the MOSFETs blew up and caught fire... The spot weld left a burn mark on the wood and one of the probes burned through the nickel strip. The takeaway, add the extra solder at the least. Add the capacitor if your unit is similar.
Did you repair it and make the changes?
@@RCVideoReviews it didn't come with extra MOSFETs
My study of spot welding found that low pressure and smooth rounded tips works best. For some reason too much pressure is not best. I have not tried this yet.
Hey Mark, Yeah, I've seen that comment quite a bit. I did wind up rounding the tips.
@@RCVideoReviews is it better with the rounded tips?
@@apexed2446 Better is arbitrary. All I can say is I get good welds. The strip is destroyed trying to remove it. I have no evidence one is better than the other.
@@RCVideoReviews fair enough, thank you! I'll experiment.
Thank you for your review and recomendation.I just buy this spotwelder & i want to make my own diy lithium 3s battery pack to provide enough power to this welder,i will use 21700-40t they are bigger and powerful than 18650.this exact battery have 40amp discharge i think,i will use 15 of them,5x3 for 3s bms i think it will have enough power to weld,My problem and quwstion for you what kind of bms it will be powerfull enough to provide enough peak amps for welding?
i see on ebay alot of different 3s bms but neither say max peak power just charging and discharging current.
can you tell my what ind of bms is in your battery pack?
Do you have a link to buy the lipo battery? I can’t find turnigy 2.2 35-70c lipo anywhere. Would be greatly appreciated :)
Seems they don't label them 70c any longer: hobbyking.com/en_us/turnigy-2200mah-3s-40c-lipo-pack.html
Just bought one of these mine doesn't have solder beds between the + terminals or from the - terminal to mosfets it has big copper slabs instead, I'm guessing the design has been refined a bit since you got yours
I've heard that.
Very good job, Congratulations.
Please help me to decide wich strips to soldering the bateries can i use in lion 18650 pack 11.1 volts 9 amps i goin to use Samsung 18650 3 amps batteries.
If you google a little, you can find charts to help you sort it out. Here's one example: www.diyelectriccar.com/attachments/strip-ampacity-pdf.120970/
I have this unit, I use it with 2 3s 8,000mah 50c packs in parallel. Works fantastic!
Great info. Dang man, that's a lot of electrons. I just finished up my first spot welded 3s2p 5000 pack ;)
@@RCVideoReviews awesome. I've been upgrading old power tools, and making 3s packs for receiver power on my bigger nitro planes, using cheap hobby king BECs, to replace old nimh packs. They work great! I have a volt meter to monitor pack voltage to keep from over-discharging. Fun stuff. I've been using molicell 2600mah 35a cells for the power tools and they are Stout! Using LG m36 3450mah 5.1a cells for the receiver packs, all 18650 of course.
@@SuperchargedJester GREAT! I just found Molicells 35a on sale @ 18650 battery store for $3.99. I've been thinking about making a 4s2p for the AR wing. With the spot welder I'm afraid of what I'm going to spend at the 18650 store. Sounds like you've got a strategy to put those things to work too.
@@RCVideoReviews I found a spare 16v 1000uf capacitor in my stash and just did my first spot weld with it modified. Much more consistent welds as opposed to without. Thanks for the tip and link to that!
@@SuperchargedJester Sure thing. Glad it helped.
The possible issue moving the positive cable near the negative is the possibility of one of the nuts loosening and shorting out.
Not an issue.
Great video Dude,,, I just purchased a similar one and haven't tried it yet so now I'm gunna be dangerous 😉 thanks !!! 😎
You’re welcome.
Get one of those pens with spring and contact switch. You'd get more consistent result... same force applied onto the contact point each time.
I just welded 6 batteries in 3s2p and it did fine. Set to 45e for attaching to batteries.
Could you tell me what cap you used and many a picture of the connect points
Cheers Clinton Jeffs
The reference video in the description shows the connections. I used an 850uf 16v cap.
Wil a 250v cap work ?from a 72v charger ?or order super capacitor
I recently bought this exact model. The part where you flowed more solder has been addressed by the maker adding a aluminum rail a few mm's thick. Question, I don't have those hobby battery packs that you used to power this unit. Is using a 12v car battery good to use? Can the battery pack from power drills be used or is the 20v too much voltage?
The spec says 12v. I wouldn't go above that. You need a battery that can deliver real punch of current. The hobby batteries work well for this.
@@RCVideoReviews that hobby battery you are using in the video is not available its out of stock everywhere I looked for a good hr online what would be an alternative in an RC battery? that has the 35c to 70c burst
You can find 3s 40c lipo batteries all over the place.
Hi just tried mine for the first time, have a brand new 12 volts boat accu (display reeds 13,5 Volts, i get the beeps but no welds any idea what might be wrong?
Think this would work on a 6s tattu r line? or would that let out magic smoke with too many volts? do I need to separate some cells and make a 3s pack?
One guy told us he used 6s on his and it worked a few times but eventually quit. I don't believe it's intended for much more than 12v.
I've was excited to get mine going but it doesn't get hot enough to make a good weld, even on 99 power setting. I initially added the capacitor mod to it to prevent the fets from frying, tried it and it's could barely weld 2 tabs together. . . so I removed the cap and tried it. . . no joy. Any idea what my issue could be? I used a 2200mAh 3S LiPo, then I tried it with a 4000mAh 4S LiPo. Same result. It was only $20 but still, I'd expect it to work for basic stuff. Wonder if connecting it to a larger 12V Lead Acid would help?
I saw another video that has more mods in it, it showed that a diode shorts and needs replacement with a resistor in series with it.
hey i bought the older rev0 version and installed the cap mod. i cant get it to power on.. im using a fully charged car battery and all i get is a quick little beep and nothing else, no power to the display or anything. i assumed i installed the cap wrong and removed it and tried powering on but am still getting the same issue. quickly beeps when pressing the power switch but no display. assuming maybe the display was faulty i tried to do a spot weld but nothing happened so it appears the whole system isnt getting power properly
You blew it by having the cap backwards its a positive negative leg on the cap
whether the direct current is on the weld
I have a 12 volt 9 ah, battery do you think this a would be a good power source?
Thanks for you quick response...I don't want to damage it I'll use a stronger battery.
It has to be able to deliver ~130amps. It's less about the capacity and more about the amperage capability. I've seen plenty of videos where a questionable 12v car battery resulted in a blown mosfet.
No page found for amazon link from the description :(
Unfortunately the sellers move in and out of stock so the pages die. Search for 18650 spot welder on Amazon and you'll find dozens of options.
There is another model with the screen to the right, is that the old or new version?
I don't know.
What thickness of nickel strip did you use?
0.1mm
just got mine and was noticing my lipo wires and pack was getting warm after a few welds so I shut it off ... don't think that's a normal or safe thing to get the lipo 3s warm
Sure it is. You're hitting it with a crap-ton of current every time. You have to pace yourself. This is not an industrial spot welder.
Good video
It was funny you jump.
I was laughing
But thank you for a good laugh and a good review. Going to get one for my small work but will not go higher then 35 setting
Hi ...The motorcycle battery 12V 12Ah 150A will be suitable for welding ?
As long as it can deliver the amperage. That's the key to the whole thing.
I heard that they are ok for the first 10 or do welds, after that kaboom... hows it still going?
Mine has made it through a 3s2p with about 3-4 welds per tab. I've done a few demos for friends/family too and it is still working ok.
Can I spot weld 18650 at full charge capacity voltage
can you link the Nickle strip you used please?
Here it is: amzn.to/3o4QWtn Make sure you use the right thickness for your current demand.
What is the voltage and AH capacity of the battery used ?
I used a 3s2200.
What else can you use to power that spot weld. Can you get a power adapter ?
It has to deliver 120-140amps. I doubt any power adapter would do. You can get the same LiPo I used for $15. Add $20-$30 if you need a charger.
So is that solder trace for the negative (that you bypass) used as a current shunt to control welding current?
I meant positive side, sorry.
The positive side is continuous the moment you connect a battery. The negative side is switched by the mosfets.
Will bigger capacitor make its performance better? Like, 10,000 uF / 50V ?
I don't think so. It's not holding the current for the weld. It's just there to protect the control circuit.
The positive trace is meant to be like a fuse if the mosfet get shorted, that's why they use 2 srew terminals for the positive . That trace can't provide 300+amps so you don't get a fire if everything get shorted.
That's not true at all. I've seen them catch fire in the box stock config. More than once.
@@RCVideoReviews i am not talking about saving the mosfets from a bad battery. i am talking about saving everything from a good battery by accident.
if you have a bad battery we all know what happens, a single mosfet will burn. you will see the flame and probably you will remove the electrodes.
now if you have a good battery and for some reason the two electrodes get stuck together all cca from the battery will flow to the whole system and the mosfets won't burn cause they can handle the amperage. the trace then will burn from the excessive amperage.
if the battery is good and the mosfet shorted the same applies, the trace won't handle all CCA amps.
if the mosfets are shorted and by accident the electrodes stuck together, the same applies, practically you short a full charged battery and there is nothing to stop it.
same if a short happens before the mosfet , the trace will save the cables and the battery.
you are saved from a big fire/melt of cables, you are not saving the mosfets.
if you don't use a car battery and you use a lipo, i really don't think you want to short it for long.
all decent spot welders (malectrics/kweld) have a 300A fuse in the + line from the battery to protect the battery and the cables , not the mosfets. that fuse is right after the battery terminal (not the same with the trace) but at least is extra protection. think about it you have a unit that shorts a full charged high amperage battery and there is no fuse anywhere (some guys use bigger cables and copper in the traces so there is nothing to hold the amps if something goes wrong).
@@BeetleJuice1980 That's a pretty poor excuse for a fuse. I wouldn't rely on it and I wouldn't trust it. There's no chance that solder is applied in a way where it could possibly result in a measured fuse. Sorry, not buying it.
@@RCVideoReviews It's obviously not measured, that's not the point. It's a cheap design, it's a McGyver fuse! It makes sense to me. I can't see why else they'd put it there.
@@geometerfpv2804 I can't see why they couldn't figure out to put a capacitor across the control circuit either but here we are. If you want to use it as a fuse you can certainly do that. It won't cost you more than a cheap dinner out.
What battery you using to powerup that spot weld
A 3s 2200 with 40-70c
If I use a deep cycle lead acid battery would I run into the low voltage issues? I'm planning on using a 120ah one with 672 cranking amps rating. I did 20 welds without mods and I didn't have any issues, I'm still planning on adding the capacitors though. Any thoughts?
It wouldn't be a bad idea to add the cap. The issue has to do with voltage sag. The videos I've seen where the problem comes in is voltage sag and weak current delivery. I expect if the battery you've described is in good condition you should be ok, but add the cap.
@@RCVideoReviews that's what I figured. Thank you so much for the quick reply! I'm subscribing right now, wow!
Do you think this model would work nicely for welding a steel bumper onto a 1998 Ford F-150?
Uhm...probably not. :)
😂
Yea thats good mine blow a mosfet first time I used it with a too large car battery. After mosfet change its welds so weak even on 99 and 800A 890ah battery.. dont understand whats bad now
In another video I have seen that a small diode shorts, and needs replacement with a diode with a resistor in series
this spot welder is good coz I did try weld 0.3mm nickel strip succefully weld.
Awesome tutorial. This would be my first experience with spot welding and I am a lot more confident going into it.
You may have mentioned, but what are the specs of the capacitor? Do you have a link? I should have everything else.
470 1000uf 🤙🏽
I used a 25v 850uf cap. Anything to 1000uf and over 12v should be fine. It's not hard to do this at all.
@@RCVideoReviews I would stick with the 25V cap, which is generally the next step-up in voltage from 10V, I believe. If they made a 12V cap (which I don't believe exists) you would be operating above its maximum rated voltage if connected to a freshly charged motorcycle or car lead-acid battery, which is aprox 14.4 Volts.
Thankyou can u tell me more about capacitors!???
What question do you have? I used 1000uf 35v
Do you think this is powerful enough to weld on button tops?
It welded the bottoms just fine.
2 years later, most direct me to the Kwelder.
Can i spot weld sterling silver with it?
I couldn't tell you as I've never tried.
Can you go TOO big on the battery you use for this mini spot welder? I've got a 12v, 100ah, marine deep cycle battery that is capable of 800cca. I don't think I have to worry about under-powering the mosfets? I'm still planning to solder in the 1000uf 16v capacitor, but is it necessary when using such a large power source?
Just keep the voltage correct. The weld is a dead short with controlled timing by the controller.
@@RCVideoReviews - I don't think I'll get a voltage sag, like I've seen in other videos, because of having such a large battery that is capable of (literally) cranking out a lot of amps. At the same time, I already ordered a 1000uf, 16v capacitor, so I'll just wait, solder that bad boy in, and hopefully I won't have any "magic smoke" issues.
i found it best not to push the probs down to hard on the nickel you get a better weld that way less resistance
I haven't done any testing, but I pressed hard enough only to ensure the nickel strip made good contact with the battery terminal.
What size and type of nickel used? Is it plated or pure
Link is in the description to the exact strips I used.
I would be interested to hear what others think of these welders because I bought one a few weeks ago, did the Cap mod before using it, saw the soldered link on the PCB and connected my leads direct to reduce the resistance, basically the same as RC vid reviews mods. My results have been mixed. welding two pieces of tabs together can produce a 'strongish' weld but when trying to weld the tabs to a battery the zap just isn't there. I perhaps need to up the current available and try again.
What power source are you using? I wound up using 45e and a 12.1+ v 3s LiPo and the welds worked pretty well. I charged at 5a, discharged at 8a and it did well.
@@RCVideoReviews I tried 3S 2200mAh 35c I haven't reduced the length of my input power leads yet but that should help as they do get warm. I do think there's potential for these little units but like all the Cheap-end electronics it can be a bit hit and miss. I will certainly try increasing the potential amps available to give it another shot.
Yeah... not enough water in the barrel won't produce a strong stream at the output.
@@RCVideoReviews What is minimal voltage 3s Lipo for good weldig?
@@Ziomal716 The voltage is dictated by the fact that it's 3S, 4.2 volts per cell fully charged. The manufacturer recommends a 3S with 50-60C discharge rating, 5000mah+.
Thanks!
Thank you for hitting the tip jar.
Putting too much pressure will result in a bad weld, with the setting at 20 or 25 will make a strong weld if you just use light pressure
Nah, it's fine. It welded perfectly. Good tight bond and the material is destroyed trying to remove it. No problem.
hello RC the battery you used is not available right now what specs should I look for in a rc lipo battery to use instead..having a hard time duplicating the specs of that turnigy 2.2 with a 35c to 70c burst discharge, I wanted to copy what you did but need the battery minimum and max specs to look for id appreciate if you or someone would help in a RC LIPO BATTERY
Any 3s cell with 40c+ should do the job. Look for rcbattery.com usually has the right kind of batteries for this device.
@@RCVideoReviews thank you for quick response
so this would be ok? 8000mAh 11.1V 100C 3S Lipo Battery
Some say you're NOT supposed to press hard. Softer press gives more resistance, which causes more metal to melt.
Iv'e tried the soft touch and thought it was pretty terrible. The bond I got in this video is still going strong a year and a half later.
you dont need to push hard the prove. if you do that, the prove will burn the strip and produce a little connection.
ok
What type of mosfets are they...part code? ....how would I describe them in order to purchase?
I'm not sure. I can't read the markings.
The ones on mine are 4n04r8
can someone link me to the correct parts to buy.? the cap and and mosfets. I SMOKED MINE FIRST TRY.
Read the number off the mosfet and its any voltage over 12v and 1000uf capacitance
Did you have to use the second battery, or was the on battery ok?
I don't follow...?
@@RCVideoReviews in the video you said that if if you didn’t get enough current from the lipo you had connect, you would connect another one….did you have to use a second battery!
Ok, I have over 800 videos. That one was published ALMOST three years ago. I answer thousands of questions every year. You'll have to forgive me if I don't remember every detail of every video.
For my project a 2nd battery wasn't required. Yours might depending on how many welds you make.
@@RCVideoReviews cheers
You are putting too much pressure during the welds. Lay off the force and your welds will be much more reliable. There only needs to be enough pressure to make the contact between the two surfaces, you should not jam one into the other. That reduces the resistance and therefore the heat of the welds making them unreliable.
It must be hard to see it in the video, but that's about all the pressure I put on. Just enough to hold the strip still and keep it flat.
Does the voltage of the capacitor matter? And if so what voltage should I use?
I used a 25v cap. Just don't use something lower than your input voltage.
@@RCVideoReviews thank you for the quick reply 🙏🏼🙏🏼
the amazon link is broken
It looks like the seller I got mine from doesn't list them anymore. You can search for DIY 18650 Spot Welder on Amazon and you'll see them.
Hi sir, Can I use a 12v 5.0ah battery, Can I know what is the minimum value required for this spot welder ???
12v is ok as long as it can deliver the amperage.
@@RCVideoReviewscan use battery 12v 5.0ah...
Almost a year later.. Still working?
Yup.
Can you hook this up to DC current?
Input power is DC, yes.
After spending a few thousand on the heli or aircraft i would never risk its future on home made lipo packs....for me it has to be factory made if its a lipo...i think it would be seen as a modification in the UK and therfore our BMFA insurance would not cover them. We have to keep to stock, we cannot even put in oversized motors if we want to keep to the BMFA regulations.