No matter if english is not your 1st language. People all over the world can understand you perfectly. 2nd. No stupid accompanying music. 3rd. Very clean high quality camera and lighting. This worth more than a like. !!! Take care my friend !
Test first *_then_* take it apart! Yes, I know Dave's saying but this was almost an example of not being able to test it before getting replacement parts. Testing it first also gives a base line to confirm that it was re-assembled correctly and no damage was done. It also verifies that it was indeed in working order when delivered. To hold it down while you are pushing up I would suggest first deciding where on your desk you will be mainly using it and then add some cloth strapping that can be connected to the underside of your desk. Various methods would work. Having a comfortable working position that allows both hands to hold the battery in place before your foot pushes the switch will provide a consistent quality.
You are right, there are situations where you would want to test before taking a part and I tend to do that with more expensive items. However with this piece of gear I was more confident than usual. I will find a good setup for working with the machine on my desk but the pedal is not needed, I can operate it with just the pressure switch in the welding arms. Though I can see how having a pedal switch would allow for better positioning before hitting the trigger with the pedal.
The transformer on a spacer is there simply to keep the switching noise down, by removing the core of the transformer from the steel chassis. The power supply for the electronics looks like it is a capacitive divider, so the entire control circuit is live at mains potential, including that foot switch. I would investigate inside it, and add an extra plastic isolating sheet to wrap around the microswitcg they use, if there is not already one there, as paint is a poor insulator. Power supply could also do with a larger value inrush limiting resistor and a MOV before the capacitor, as well as another big MOV across the power input ( after switch and fuse) and also a snubber across the TRIAC as well as upgrade. The switches are probably multiplexed via the display drive shift registers, probably by using one of the outputs that drive the LED's per switch, and then bringing the return back via resistors to the data out driving the shift registers, and scanning by simply turning the output back to an input with weak pullupwhen the shift registers are outputting for a switch, and seeing if it is high or low. then set a register internally and carry on scanning, and use software debounce. No extra pins required but slightly more code, and you need 3 pins anyway to drive the shift registers, clock, data and latch, and data can be tristated and used for input when clock is stable. Displays are probably Charlieplexed, there are libraries to do so off the shelf. Decent enough for occasional use, the thing that will fail is the little capacitive divider power supply, and that will result in the unit still having a display in the beginning, but it having unreliable pulsing, with the display flickering during pulses. Replace the film capacitor with a new class X2 one, along with the cheap electrolytic and it will run fine again. The second winding on the power transformer is there to provide an input to the micro so it can count mains pulses applied to the load, used to determine the transformer has been turned on by the triac for power control, and another input is used to trigger the triac, by providing a mains synchronous input to it as well for zero crossing. 6 pins available, 3 used by the display and 2 for input and output sensing for zero crossing, leaving one pin for driving the triac. I think the extra components and space are for a bigger micro on the more optioned units, and the extra board is there for that as well.
Wow a nice in-depth analysis, really useful info, thank you for sharing this. I also saw there is a small transformer on the board, I haven't traced the pins but I was guessing it might be used for isolating the pedal switch? I am not going to use the pedal switch anyway because I like to operate it by pushing on the welding arms.
@@voltlog Sorry, looks like there is a tiny switcher in there, but as they do not isolate the triac from the micro it still is mains connected, just they are using more gate current to drive it. Probably there for the higher option units that need 200mA or more of power at 5V to run, and as the output is not isolated they use the feedback pin to do regulation as well. Half wave rectifier on the input, no inrush limiting aside from capacitor ESR and snaking thin traces, and probably not too long a life for that switching chip. Would be good to upgrade with a MOV there across the capacitor, and a series fusible resistor as well, hich if i ever get one I would do. Should build my own though, got the transformer wound, and some tungsten welding rods, must just build a set of holders and put it together with a simple timer to allow a short pulse of current, though I will probably be using a mains contactor instead to do the switching in the beginning. transformer is a little oversize, made from an old UPS transformer, in the days when ferroresonant UPS units were de facto for anything over 1kVA. I just removed the secondary and the shunts, and wound in 3 turns of 000 gauge wire instead into the former, then soldered a set of lugs to the wire ends, as I have absolutely no other way to crimp that size lug, just use a gas torch and a lot of solder, instead of the proper hydraulic crimper.
@@SeanBZA cool, sounds like your DIY version would have plenty of power and it's only wise to do the switching at the mains side because of lower current. Another thing I'm worried with my DIY version is that it may trip the fuses on the first go, but I guess I'll find out soon.
@@voltlog They give a fast blow fuse of 10A with these, probably best to get some 8A slow blow fuses for when the original one and the spare blows. You can see after a few uses the fuse element in the original fuse will be slightly discoloured and will have sagged a little as it is heated up to softening point every cycle. Will work for a long time with light use though. Best inrush limiting with these is to use Chinesium extension cord, a long one, where the cord resistance actually is an advantage here.
I have the same spot welder. Mine had such a thick layer of paint under the grounding screw that the case was not even connected to ground. The foot switch smells like the type of plastic/rubber that could give you cancer. I always have to hold the welder down with one hand while holding the batteries with the other so it doesn't move up, if I reduce the pressure on the knob the welds will not stick. The transformer spacer could be either to reduce noise, reduce the resistance or reduce the cost due to the shorter copper leads. The fact that you can only set it to 2 pulses and cant adjust the time is kinda ridiculous. I measured the peak amps with a clamp meter and the max I got was 235A, far away from the 800A written on the enclosure. I will probably DIY a board for this with propper settings/interface using an OLED display and a modified microwave transformer. The enclosure itself is ok.
I think you are right, the main reason for the stand is the short length of the transformer output wires. I will have to do a follow-up video and check the grounding connection.
Find a steel plate to make a heavy stand for it, so that you can bolt it down to the plate, and have the plate come out the front, with a thin rubber mat on the front section to not short out the cells, so you have extra mass and a lever arm to support the bottom to the case. Just has to be 10cm/4inch wide steel strip 6mm/0.25inch thick, long enough to go all the way to the rear and stick out the front a little past the electrodes. Bolt to case and put the rubber feet on it instead of the case. Being so thick you can drill and tap threads into it, to use existing holes in the case as well.
@@RandomHacks Checked the grounding, it's 1.1 Ohms from the end of the power cord up to the front panel, that is with the thick black paint at the grounding point. After a cleanup of the paint it dropped to 0.5 Ohms. I also measured the current with an AC clamp meter, on the thick secondary output wires, I am getting values over 100A but it's hard to get consistent readings with my cheap clamp meter, because the pulse is very short.
@@voltlog 1.1 Ohms not bad! Mine was in the order of megaohms. Thanks for the follow up 👍 I have a PEAKMETER PM2108 clamp meter it is cheap too but seems to do the job.
The *transformer stand* has a few purposes. I've seen a couple guesses here but I _think_ they missed the mark. I believe the reasons are: _1st:_ they want to keep the external front panel contacts high enough to fit a variety of battery types and other jobs. This also allows a short pressure adjustment knob length and the terminal contact assembly may be a common assembly used in many different models and brands. _2nd:_ it is cheaper to add this stand than to have longer heavy gauge wires. This same transformer may be in use in another product and it was cheaper to add the stand than order a "custom special order" transformer with the longer wires. Shorter wires also keep the voltage drop down for the same gauge wire. _3rd:_ the extra holes in the stand allows for different transformer sizes. Either for more power or a different AC mains voltage. They might also have different suppliers for these thus using this stand made these changes easy to accommodate. _4th:_ this also allows the design to easily adapt a larger transformer for the next upgraded model in the same case. This again reduces future upgraded model costs to basically the transformer and front panel labelling, etc. IMHO any way. *_Merry Christmas_*
I agree with SeanBZA on the spacer... although I see an additional benefit: the space allows for a much shorter run of secondary lead to the head, reducing I2R loss. The programming should be changed to provide for setting 00 on the duty cycle control. 00 is meaningless, so I'd start at 01 and end at 99.
Another possibility of the plastic riser for the xformer is for short connection to the external terminals. The transformer may have had short secondary lead length from the manufacture which is fine if the external terminals are near the lower section of the face plate but not the case here. With the high current, keeping the leads short is a good idea and trying to lengthen the leads would be very problematic. Just a thought.
I´have the same one. My fuses always nocked out when i try to point a battery. I replace the rubbish transformer (one twist.... really only one twist!!!) with an transformer from an microwave with 10x 16mm seconrary twists, now the machine is well working, no fuses triggert from the welder.
Transformer stood off chassis to reduce high magnetic field from pulling on steel chassis when welder is pulsed. Can be very loud. Thanks for upload. helped me decide to buy one :-)
Great video ! The point in changing the board on this sucker is to avoid the major trouble which is tripping the breaker at every use ! I'm searching someone who can explain how to do that because it's very annoying. And the arm length is a pain in the butt as well. i really want to upgrade mine.
Merry Christmas to you .... I bought the SUNKKO 788H Model , It's a fair model as well A Few more Adjustment on it But overall For Occasional Use it does the job ... Thank you for the Review ....
The block below the transformer could be for acoustic decoupling. i have some big linear power supplies and the hum from the transformers is audible in the entire house
Ok I see what you mean but it just seems something that our Chinese friends would not consider important (acoustic issues), I'm guessing they did it for the length of the secondary output wires like someone else mentioned in the comments.
The 'Nickel' strips that come with those machines are just nickel plated steel. Resistance is higher in steel so they weld easier but carry less current.
They say so on the package "nickel plated iron". I don't have any pure nickel tabs to test.. But measuring on my bench meter on the 0.2 mm strip I get 1mohm over the entire length. I would call that pretty good for most uses.
@@voltlog Yes, but as they hopefully put in an interwinding tape you have 3 layers of insulation, and the mains winding is a lot more likely to short to itself than the secondary, even though the secondary is made from probably 30 parallel enameled copper wires to fit the area better. Probably wound as mains side nearest the core, a layer of tape, the single layer of the feedback winding, another layer of tape and then the secondary, with a final tape outer layer , then twist the secondaries together, solder pot tin them, then add the spiral sleeve.
So many better solutions. These Sunnko welders are old school. Please review other kits, kweld jpwelder and several Aliexpress versions. We desperately need your review
I would be happy to review others but so far only banggood offered to send one for review and the budget doesn't allow me to go and buy all these different welders for review.
VoltLog I’d happily fund this model, but if time does not allow its ok. www.aliexpress.com/item/Spot-Welders-control-Board-100A-Digital-display-Spot-welding-time-and-current-controller-panel-timing-Ammeter/32889870922.html?spm=2114.search0104.3.9.94da23aanie5O9&ws_ab_test=searchweb0_0,searchweb201602_1_10065_10068_10130_10890_10547_319_10546_317_10548_10545_10696_453_10084_454_10083_10618_431_10307_537_536_10059_10884_10887_100031_321_322_10103,searchweb201603_1,ppcSwitch_0&algo_expid=6c9e12b0-2480-4649-bbbd-18824c3e62bb-1&algo_pvid=6c9e12b0-2480-4649-bbbd-18824c3e62bb
Hola, debió haber probado la lámina de 0.2 en el borne negativo y una lámina de por ejemplo 10mm de ancho, ya no quedaría tan fuerte, saludos. Hello, you should have tried the 0.2 sheet on the negative terminal and a sheet of for example 10mm wide, it would not be so strong, greetings.
Plastic block under the transformer - maybe it allows shorter heavy gauge wires to the terminals. ? 1" plastic block saves 2" expensive heavy copper wire ?
This spot welding machine transformer looks smaller than a microwave oven transformer. I don't know how it has 1500 watts. Have you done the measurement? Thanks. On the other hand, if the time is too short for measuring, you can try measurement on the primary side.
All the strips that came with the unit created good welds and they were nickel coded steel but the pure nickel.015" I purchased separately would not weld. Any suggestions?
Thanks for the nice review. I have the exact same model and I'm using it in a 230V electric system but it is tripping my 16A circuit breaker. Out of curiosity, what was your amp limit on your AC installation you used for this test?
16A classical ceramic fuse protection on my circuit but I've heard this issue before from another viewer, it might be an issue with your unit, you should contact the seller for warranty purposes.
I get the same results from a makeshift spot welder I made from a 12v tractor battery 350 cold cranking amps, a Starter Solenoid for a 1978 Ford Bronco, a heavy duty momentary switch, Copper nails to make the contact for welding, 60 amp wire double insulated that fit inside the SODIAL(R) 60 Amp - 12 Way Strip Terminal Block Strip - Electrical Wire Connector Amp:60A Connector Block www.amazon.com/gp/product/B074MZKWQK/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 I'm upgrading the wire, but I can still make many welds without the wire getting warm. This is what I had laying around to make it in a pinch. I just tap the switch as fast as possible. You really want solid nickel strips because the one here rust, the plating is too thin.
Mr. Brother, I bought it, but I plug the machine and when I start to punish, that is, when I do the punishment, I throw the cycloon of the house, I tried it in all the plugs in the house, but it does so. I wonder if you have any information about it, I would appreciate it Respects
I believe there are two great spotwelder projects out there. The kweld and the audrino spotwelder. I have not seen a comparison of those two. But I know they have bin at it for a long long time and many hours of work en improvements. You surly have a lot of work in front of you mate
Hi, I´ve bought this spot welder too, but it turns off the circuit breaker at 40 % current or more.. I have to solve this issue... Do you know how ? Thanks.
Can someone measure the resistance for me across the AC input I just ordered one and it fell from the box due clumsiness, it fell on the AC wire and there's a dent now, I just measured the resistance between the AC plug and the system and it gives me about 193k ohms is that normal?
Hi VoltLog, after publish your Video I bought this unit because I've just from time to time to make a new battery block, really not very often. My SUNKKO 737G has a 20Amp Fuse and I couldn't welder without eject the 16 Amp Fuse of the room. Do you have an Idea to modify the unit to can work with them under 16 Amp room fuse?
you can try decreasing the settings for welding (Time and pulses) but you might discover the weld is not good anymore so I would suggest increasing the fuse size or moving to another socket.
Could you put a link for the purchase of the transformer only. You mentioned it could be bought from Ali Express . I would like to purchase just the mains transformer. Thanks for your videos
Salut, am cumpărat recent un astfel de aparat, dar nu pot "suda cu el" deoarece îmi sare siguranta la greu. Am siguranțe automate. Recent a cedat placa de bază. Sunt in discuții cu vânzătorul să îmi trimită alta placă.
Thanks for the video, excellent work ! I hjave a quick question, I have this one and I would like to install a welding pen so it is more flexible and I can spot weld large battery packs with an hand held pen. What is your recommentation? Just connect 2 copper cables to the terminals ?
I get order on Banggood and I recived it today. When try to weld. it's making my house circuit breaker to trip, shutting down the electricity. I have 220V 16A. I can not use it. Have any advise? What can Ido?
I got the same problem. The fuse on spotwelder is F20A. It breaks in less than 20ms. So you have to change your house circuit breaker to D20A with a high breaking capacity 25KA.
@@voltlog Thank you so much! I have the 220v. I emailed Sunkko, they said you need C40 (not kidding) and that this welder is meant for "industry" and not home use
got a primary side fuse, must be good - dave lol the 788 model had the transformer directly bolted to the bottom syonyk.blogspot.com/2015/05/sunkko-788-welder-failure-and-repair.html i figured soldering 18650s with the ZD985 desoldering station works quite well, high heat capacity transfers it more quickly and doesnt heat up the cells much. id preffer the soldering way in case i gotta replace a cell or two.
So it must be true that they used the plastic riser block because the secondary wires were too short to reach the welding arms. Also it's interesting that they have a heatsink on this model, maybe I should check mine to see if the triac gets got and needs a heatsink.
Get a welder with longer lead probes. www.keenlab.de/index.php/product-category/kspot-welder-kit/. endless-sphere.com/forums/viewtopic.php?f=31&t=68865
My 737 died quickly, like after 4 welds. The Arduino and JP Welders on endless_sphere dot com are far better and have a wider range of nickel strip thickness. I burned up two Sunnko.
@@voltlog Sort of, after 3 months of fighting they sent me a new PCB and a few pennies in parts. Sadly it was such a poor PCB and build that a rebuild was too much of a pain, I ended up selling the parts and unit for 1/3 of what I paid. Additionally, the PURE NICKEL strip was pure nickel coated steel. The Arduino welders are proving to be quite a good deal. I liked the one I posted because it uses parts from a microwave instead of an SLA of LiPoly packs.
No matter if english is not your 1st language. People all over the world can understand you perfectly. 2nd. No stupid accompanying music. 3rd. Very clean high quality camera and lighting. This worth more than a like. !!! Take care my friend !
Thank you for the support!
Test first *_then_* take it apart! Yes, I know Dave's saying but this was almost an example of not being able to test it before getting replacement parts. Testing it first also gives a base line to confirm that it was re-assembled correctly and no damage was done. It also verifies that it was indeed in working order when delivered.
To hold it down while you are pushing up I would suggest first deciding where on your desk you will be mainly using it and then add some cloth strapping that can be connected to the underside of your desk. Various methods would work. Having a comfortable working position that allows both hands to hold the battery in place before your foot pushes the switch will provide a consistent quality.
You are right, there are situations where you would want to test before taking a part and I tend to do that with more expensive items. However with this piece of gear I was more confident than usual.
I will find a good setup for working with the machine on my desk but the pedal is not needed, I can operate it with just the pressure switch in the welding arms. Though I can see how having a pedal switch would allow for better positioning before hitting the trigger with the pedal.
The transformer on a spacer is there simply to keep the switching noise down, by removing the core of the transformer from the steel chassis. The power supply for the electronics looks like it is a capacitive divider, so the entire control circuit is live at mains potential, including that foot switch. I would investigate inside it, and add an extra plastic isolating sheet to wrap around the microswitcg they use, if there is not already one there, as paint is a poor insulator. Power supply could also do with a larger value inrush limiting resistor and a MOV before the capacitor, as well as another big MOV across the power input ( after switch and fuse) and also a snubber across the TRIAC as well as upgrade.
The switches are probably multiplexed via the display drive shift registers, probably by using one of the outputs that drive the LED's per switch, and then bringing the return back via resistors to the data out driving the shift registers, and scanning by simply turning the output back to an input with weak pullupwhen the shift registers are outputting for a switch, and seeing if it is high or low. then set a register internally and carry on scanning, and use software debounce. No extra pins required but slightly more code, and you need 3 pins anyway to drive the shift registers, clock, data and latch, and data can be tristated and used for input when clock is stable. Displays are probably Charlieplexed, there are libraries to do so off the shelf.
Decent enough for occasional use, the thing that will fail is the little capacitive divider power supply, and that will result in the unit still having a display in the beginning, but it having unreliable pulsing, with the display flickering during pulses. Replace the film capacitor with a new class X2 one, along with the cheap electrolytic and it will run fine again. The second winding on the power transformer is there to provide an input to the micro so it can count mains pulses applied to the load, used to determine the transformer has been turned on by the triac for power control, and another input is used to trigger the triac, by providing a mains synchronous input to it as well for zero crossing. 6 pins available, 3 used by the display and 2 for input and output sensing for zero crossing, leaving one pin for driving the triac. I think the extra components and space are for a bigger micro on the more optioned units, and the extra board is there for that as well.
Wow a nice in-depth analysis, really useful info, thank you for sharing this. I also saw there is a small transformer on the board, I haven't traced the pins but I was guessing it might be used for isolating the pedal switch? I am not going to use the pedal switch anyway because I like to operate it by pushing on the welding arms.
@@voltlog Sorry, looks like there is a tiny switcher in there, but as they do not isolate the triac from the micro it still is mains connected, just they are using more gate current to drive it. Probably there for the higher option units that need 200mA or more of power at 5V to run, and as the output is not isolated they use the feedback pin to do regulation as well. Half wave rectifier on the input, no inrush limiting aside from capacitor ESR and snaking thin traces, and probably not too long a life for that switching chip. Would be good to upgrade with a MOV there across the capacitor, and a series fusible resistor as well, hich if i ever get one I would do.
Should build my own though, got the transformer wound, and some tungsten welding rods, must just build a set of holders and put it together with a simple timer to allow a short pulse of current, though I will probably be using a mains contactor instead to do the switching in the beginning. transformer is a little oversize, made from an old UPS transformer, in the days when ferroresonant UPS units were de facto for anything over 1kVA. I just removed the secondary and the shunts, and wound in 3 turns of 000 gauge wire instead into the former, then soldered a set of lugs to the wire ends, as I have absolutely no other way to crimp that size lug, just use a gas torch and a lot of solder, instead of the proper hydraulic crimper.
@@SeanBZA cool, sounds like your DIY version would have plenty of power and it's only wise to do the switching at the mains side because of lower current. Another thing I'm worried with my DIY version is that it may trip the fuses on the first go, but I guess I'll find out soon.
@@voltlog They give a fast blow fuse of 10A with these, probably best to get some 8A slow blow fuses for when the original one and the spare blows. You can see after a few uses the fuse element in the original fuse will be slightly discoloured and will have sagged a little as it is heated up to softening point every cycle. Will work for a long time with light use though. Best inrush limiting with these is to use Chinesium extension cord, a long one, where the cord resistance actually is an advantage here.
@@SeanBZA Mine has a 20A fuse installed, also a 20A fuse provided for replacement.
I have the same spot welder. Mine had such a thick layer of paint under the grounding screw that the case was not even connected to ground. The foot switch smells like the type of plastic/rubber that could give you cancer. I always have to hold the welder down with one hand while holding the batteries with the other so it doesn't move up, if I reduce the pressure on the knob the welds will not stick. The transformer spacer could be either to reduce noise, reduce the resistance or reduce the cost due to the shorter copper leads. The fact that you can only set it to 2 pulses and cant adjust the time is kinda ridiculous. I measured the peak amps with a clamp meter and the max I got was 235A, far away from the 800A written on the enclosure. I will probably DIY a board for this with propper settings/interface using an OLED display and a modified microwave transformer. The enclosure itself is ok.
I think you are right, the main reason for the stand is the short length of the transformer output wires. I will have to do a follow-up video and check the grounding connection.
Find a steel plate to make a heavy stand for it, so that you can bolt it down to the plate, and have the plate come out the front, with a thin rubber mat on the front section to not short out the cells, so you have extra mass and a lever arm to support the bottom to the case. Just has to be 10cm/4inch wide steel strip 6mm/0.25inch thick, long enough to go all the way to the rear and stick out the front a little past the electrodes. Bolt to case and put the rubber feet on it instead of the case. Being so thick you can drill and tap threads into it, to use existing holes in the case as well.
@@voltlog Please measure the inrush current if possible. Your welds seem to stick better than mine.
@@RandomHacks Checked the grounding, it's 1.1 Ohms from the end of the power cord up to the front panel, that is with the thick black paint at the grounding point. After a cleanup of the paint it dropped to 0.5 Ohms. I also measured the current with an AC clamp meter, on the thick secondary output wires, I am getting values over 100A but it's hard to get consistent readings with my cheap clamp meter, because the pulse is very short.
@@voltlog 1.1 Ohms not bad! Mine was in the order of megaohms. Thanks for the follow up 👍 I have a PEAKMETER PM2108 clamp meter it is cheap too but seems to do the job.
The *transformer stand* has a few purposes. I've seen a couple guesses here but I _think_ they missed the mark. I believe the reasons are:
_1st:_ they want to keep the external front panel contacts high enough to fit a variety of battery types and other jobs. This also allows a short pressure adjustment knob length and the terminal contact assembly may be a common assembly used in many different models and brands.
_2nd:_ it is cheaper to add this stand than to have longer heavy gauge wires. This same transformer may be in use in another product and it was cheaper to add the stand than order a "custom special order" transformer with the longer wires. Shorter wires also keep the voltage drop down for the same gauge wire.
_3rd:_ the extra holes in the stand allows for different transformer sizes. Either for more power or a different AC mains voltage. They might also have different suppliers for these thus using this stand made these changes easy to accommodate.
_4th:_ this also allows the design to easily adapt a larger transformer for the next upgraded model in the same case. This again reduces future upgraded model costs to basically the transformer and front panel labelling, etc.
IMHO any way. *_Merry Christmas_*
I think you are right, the main reason for the stand is the short length of the transformer output wires. Merry Christmas!
5th: Less vibrations of the case because of the magnetic field leakage.
I agree with SeanBZA on the spacer... although I see an additional benefit: the space allows for a much shorter run of secondary lead to the head, reducing I2R loss.
The programming should be changed to provide for setting 00 on the duty cycle control. 00 is meaningless, so I'd start at 01 and end at 99.
Another possibility of the plastic riser for the xformer is for short connection to the external terminals. The transformer may have had short secondary lead length from the manufacture which is fine if the external terminals are near the lower section of the face plate but not the case here. With the high current, keeping the leads short is a good idea and trying to lengthen the leads would be very problematic. Just a thought.
yup I think this could be it, thanks!
Bravo frate! Felicitări!
Spot welding is cleaner than soldering. Easy to dismantle the connections.
I´have the same one. My fuses always nocked out when i try to point a battery. I replace the rubbish transformer (one twist.... really only one twist!!!) with an transformer from an microwave with 10x 16mm seconrary twists, now the machine is well working, no fuses triggert from the welder.
are u german? i want do the same but some help might be needed
Could you give more info on what you did, I am quite interested.
With mains FUSE!
Not that Weller fuseless rubbish. :)
These tabs bundled probably Ni plated steel.
If it welds 0.2mm pure nickel, im sold.
They say so on the package "nickel plated iron". I don't have any pure nickel tabs to test..
Transformer stood off chassis to reduce high magnetic field from pulling on steel chassis when welder is pulsed. Can be very loud. Thanks for upload. helped me decide to buy one :-)
Great video !
The point in changing the board on this sucker is to avoid the major trouble which is tripping the breaker at every use !
I'm searching someone who can explain how to do that because it's very annoying. And the arm length is a pain in the butt as well. i really want to upgrade mine.
Merry Christmas to you .... I bought the SUNKKO 788H Model , It's a fair model as well A Few more Adjustment on it But overall For Occasional Use it does the job ... Thank you for the Review ....
Thank you, Merry Christmas!
The great review! I've never seen one work before this is so cool to see that! :-) Merry Christmas to you and yours and a Happy New Year as well! :-)
Merry Christmas!
I was also keen to see one in operation.
The block below the transformer could be for acoustic decoupling. i have some big linear power supplies and the hum from the transformers is audible in the entire house
Ok I see what you mean but it just seems something that our Chinese friends would not consider important (acoustic issues), I'm guessing they did it for the length of the secondary output wires like someone else mentioned in the comments.
The 'Nickel' strips that come with those machines are just nickel plated steel. Resistance is higher in steel so they weld easier but carry less current.
They say so on the package "nickel plated iron". I don't have any pure nickel tabs to test.. But measuring on my bench meter on the 0.2 mm strip I get 1mohm over the entire length. I would call that pretty good for most uses.
VoltLog a big difference in performance. Plated is undesirable.
Nice review.
My heart was jumping when you touched those welding arms with the machine switched on! :)
Less than 5V on them, even though the current will be over 100A, will not shock you, provided the mains side insulation is done correctly.
Yeah, it's a bit of a gamble, you're relying on good transformer insulation.
@@voltlog Yes, but as they hopefully put in an interwinding tape you have 3 layers of insulation, and the mains winding is a lot more likely to short to itself than the secondary, even though the secondary is made from probably 30 parallel enameled copper wires to fit the area better. Probably wound as mains side nearest the core, a layer of tape, the single layer of the feedback winding, another layer of tape and then the secondary, with a final tape outer layer , then twist the secondaries together, solder pot tin them, then add the spiral sleeve.
So many better solutions. These Sunnko welders are old school. Please review other kits, kweld jpwelder and several Aliexpress versions. We desperately need your review
I would be happy to review others but so far only banggood offered to send one for review and the budget doesn't allow me to go and buy all these different welders for review.
VoltLog I’d happily fund this model, but if time does not allow its ok. www.aliexpress.com/item/Spot-Welders-control-Board-100A-Digital-display-Spot-welding-time-and-current-controller-panel-timing-Ammeter/32889870922.html?spm=2114.search0104.3.9.94da23aanie5O9&ws_ab_test=searchweb0_0,searchweb201602_1_10065_10068_10130_10890_10547_319_10546_317_10548_10545_10696_453_10084_454_10083_10618_431_10307_537_536_10059_10884_10887_100031_321_322_10103,searchweb201603_1,ppcSwitch_0&algo_expid=6c9e12b0-2480-4649-bbbd-18824c3e62bb-1&algo_pvid=6c9e12b0-2480-4649-bbbd-18824c3e62bb
Interested?
@@thomasjaszewski64 czcams.com/video/QFEyG6fYaQY/video.html
Thanks for sharing and Merry Christmas !
thank you, happy holidays!
Thank you for reviewing this rather russian style chinese welding machine. I would assume it is good enough for a once in a while usage scenario.
Thank you and Merry Christmas!
Hola, debió haber probado la lámina de 0.2 en el borne negativo y una lámina de por ejemplo 10mm de ancho, ya no quedaría tan fuerte, saludos.
Hello, you should have tried the 0.2 sheet on the negative terminal and a sheet of for example 10mm wide, it would not be so strong, greetings.
Good job Thanks
I have the 120volt unit and it fails to spot weld 0.015" x 10mm pure nickel strip. What are you using for strips and settings?
The Transformer has no second - secondary wiring - its just a Temp Sensor.
But thank you very much for your Upload! :)
thanks for u video but please dear what best or normal or standard amp with timer to use 18650 battry?
Plastic block under the transformer - maybe it allows shorter heavy gauge wires to the terminals. ? 1" plastic block saves 2" expensive heavy copper wire ?
tranformer fixed on plastic... to get . less noise
This spot welding machine transformer looks smaller than a microwave oven transformer. I don't know how it has 1500 watts. Have you done the measurement? Thanks.
On the other hand, if the time is too short for measuring, you can try measurement on the primary side.
All the strips that came with the unit created good welds and they were nickel coded steel but the pure nickel.015" I purchased separately would not weld. Any suggestions?
The rubber is there to isolated the transformer from the case. 220v could kill you on a 30 amp breaker
Thanks for the nice review. I have the exact same model and I'm using it in a 230V electric system but it is tripping my 16A circuit breaker. Out of curiosity, what was your amp limit on your AC installation you used for this test?
16A classical ceramic fuse protection on my circuit but I've heard this issue before from another viewer, it might be an issue with your unit, you should contact the seller for warranty purposes.
DOES IT WORK WITH 220V 16AMP? someone said that it needs a 25A breaker🤔
I get the same results from a makeshift spot welder I made from a 12v tractor battery 350 cold cranking amps, a Starter Solenoid for a 1978 Ford Bronco, a heavy duty momentary switch, Copper nails to make the contact for welding, 60 amp wire double insulated that fit inside the SODIAL(R) 60 Amp - 12 Way Strip Terminal Block Strip - Electrical Wire Connector Amp:60A Connector Block www.amazon.com/gp/product/B074MZKWQK/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 I'm upgrading the wire, but I can still make many welds without the wire getting warm. This is what I had laying around to make it in a pinch. I just tap the switch as fast as possible. You really want solid nickel strips because the one here rust, the plating is too thin.
It's nice that you used what you had around. I sometimes like to build projects with what I have around.
Nice item
Merry Christmas!
Merry Christmas!
Mr. Brother, I bought it, but I plug the machine and when I start to punish, that is, when I do the punishment, I throw the cycloon of the house, I tried it in all the plugs in the house, but it does so.
I wonder if you have any information about it, I would appreciate it
Respects
nice!! 💪 👷🏻
I believe there are two great spotwelder projects out there. The kweld and the audrino spotwelder. I have not seen a comparison of those two. But I know they have bin at it for a long long time and many hours of work en improvements. You surly have a lot of work in front of you mate
Hi, I´ve bought this spot welder too, but it turns off the circuit breaker at 40 % current or more.. I have to solve this issue... Do you know how ? Thanks.
Can someone measure the resistance for me across the AC input I just ordered one and it fell from the box due clumsiness, it fell on the AC wire and there's a dent now, I just measured the resistance between the AC plug and the system and it gives me about 193k ohms is that normal?
Whats the thickest wribbon it can weld? Im using .6mm thick strips that can handle 80 amps.
Hi VoltLog, after publish your Video I bought this unit because I've just from time to time to make a new battery block, really not very often. My SUNKKO 737G has a 20Amp Fuse and I couldn't welder without eject the 16 Amp Fuse of the room. Do you have an Idea to modify the unit to can work with them under 16 Amp room fuse?
you can try decreasing the settings for welding (Time and pulses) but you might discover the weld is not good anymore so I would suggest increasing the fuse size or moving to another socket.
Merry Christmas Florin ;-)
Merry Christmas!
Could you put a link for the purchase of the transformer only. You mentioned it could be bought from Ali Express . I would like to purchase just the mains transformer.
Thanks for your videos
He said "it would be nice to find them on Ali Express", not that you can find them on Ali Express.
Unfortunately I have never seen something like this on ali.
I got one I really like it for the price and it’s nice that it comes with battery tags
How reliable is this battery welder ?
Can you measure the open circcuit voltage?
Salut, am cumpărat recent un astfel de aparat, dar nu pot "suda cu el" deoarece îmi sare siguranta la greu. Am siguranțe automate. Recent a cedat placa de bază. Sunt in discuții cu vânzătorul să îmi trimită alta placă.
Hello friends, hope you are well. Can I ask what's the glass fuse rating on the back? Many thanks
Hello, its a F20A glass fuse with a breaktime less than 20ms. Hint: Your home breaker should have D20A with a high breaking capacity of 25KA
If the transformer powers the other components then how does it switch the transformer to weld ?
your explaination are so good, how can i contact you, i want to sub/dub these video to vietnamese and re-up it
Thanks for the video, excellent work ! I hjave a quick question, I have this one and I would like to install a welding pen so it is more flexible and I can spot weld large battery packs with an hand held pen. What is your recommentation? Just connect 2 copper cables to the terminals ?
I get order on Banggood and I recived it today. When try to weld. it's making my house circuit breaker to trip, shutting down the electricity. I have 220V 16A. I can not use it. Have any advise? What can Ido?
I got the same problem. The fuse on spotwelder is F20A. It breaks in less than 20ms. So you have to change your house circuit breaker to D20A with a high breaking capacity 25KA.
@@manfredkuhn3624I replaced to microwave transformer.
What circuit breakers do you use?
My 16a blows every time =D
@@FrankyBmagic B16
@@voltlog Thank you so much!
I have the 220v.
I emailed Sunkko, they said you need C40 (not kidding) and that this welder is meant for "industry" and not home use
Hi, is the sunkko 787a+ or sunkko 788h batter?.
I wouldn't know, I just have the 737G model.
Service point in Hyderabad India
Is this the 110v or 220v device ?
I was testing the 220V device
I have the 115 volts and the weld don't stick
I have one and it doesn't really weak welds, I would not recommend it to anyone.
I think it is easy to attach extending thick copper cables and use it for larger battery pack.
Many kits on Aliexpress. Very cheap
got a primary side fuse, must be good - dave lol
the 788 model had the transformer directly bolted to the bottom syonyk.blogspot.com/2015/05/sunkko-788-welder-failure-and-repair.html
i figured soldering 18650s with the ZD985 desoldering station works quite well, high heat capacity transfers it more quickly and doesnt heat up the cells much. id preffer the soldering way in case i gotta replace a cell or two.
So it must be true that they used the plastic riser block because the secondary wires were too short to reach the welding arms. Also it's interesting that they have a heatsink on this model, maybe I should check mine to see if the triac gets got and needs a heatsink.
Dungu...
Shit welder triggered my 25A fuses they told me to replace it with 70a fuses I asked them for the CE report or a refund, guess what I got...
Neither?
The welder does have a 20A fuse which should have triggered before. Unfortunately these cheap machines don't have a CE certificate, they don't bother.
8:27... Lousy design.. The rocker switch is mounted upside-down.
Normal standard operation is push on top to turn 'ON'.
Get a welder with longer lead probes. www.keenlab.de/index.php/product-category/kspot-welder-kit/. endless-sphere.com/forums/viewtopic.php?f=31&t=68865
I think I've seen that one before here in the comments, it's a pretty nice unit, certainly higher quality.
My 737 died quickly, like after 4 welds. The Arduino and JP Welders on endless_sphere dot com are far better and have a wider range of nickel strip thickness. I burned up two Sunnko.
Did you at least manage to get a refund for the dead Sunko?
@@voltlog Sort of, after 3 months of fighting they sent me a new PCB and a few pennies in parts.
Sadly it was such a poor PCB and build that a rebuild was too much of a pain, I ended up selling the parts and unit for 1/3 of what I paid. Additionally, the PURE NICKEL strip was pure nickel coated steel. The Arduino welders are proving to be quite a good deal. I liked the one I posted because it uses parts from a microwave instead of an SLA of LiPoly packs.
@@thomasjaszewski64 wow, that's a bad experience you've had with these so i can understand your view.