78 × 18650 cells welded. Arms are sore, heart is full
The customer's old case is only 130×370, so I measured three times before I dared to cut anything. 13S6P, 0.2 nickel-plated strip, UF20B at gear 38 — watching the welds light up one by one is seriously addictive.
Halfway through, the welding pens touched and blew a hole right through one cell. Swapped it out and started over — newbies, remember this: position first, then press. Don't rush.
BMS goes in tomorrow, it goes back to the customer the day after. Will report back.
Help: the area around the weld turns black, with a ring of burn marks too. Is the gear too high, or was the nickel strip not pressed flat? 0.15 nickel-plated on the H1, I'm using gear 45.
It tears off when I give it a pull, so I don't feel good about putting it in a pack. Could any old hands point me in the right direction? Thanks!
My 220V portable power station finally works — hot pot in the backyard tonight
54 × 18650, 3S18P, 12.6V 36Ah. The inverter does 600W continuous, 1200W peak. The moment I plugged in the rice cooker my heart was racing — rock solid!
Welded with the P60F, double-layer nickel strip in one pass, not a single cold weld. It took two evenings; the hardest part wasn't the welding, it was cramming this pile of modules into the storage box and still leaving room for airflow.
The video shows the whole process. If you want to build one, follow along, and ask questions in the comments.
My first self-welded power bank, 20000mAh, and it lights up!
I was always too scared to touch spot welding — afraid something would blow up. The day my U3 Pro arrived I practiced on scrap nickel strip all afternoon, and today I did it for real.
Six salvaged cells, sorted by internal resistance. Tested it with a flashlight after welding: in 38 minutes it charged my phone full twice.
Grinning like I'd found money on the street. My wife says I'm acting like a kid. Yep.
The 2026 H2 has landed in the warehouse — the first 500 units ship today
Color screen, dual pulse, gears 1–99, welds up to 0.25mm nickel-plated strip. This generation switches to new grade-A cells, with 40% more battery life than the last one.
If yours has arrived, snap a photo of it on your desk, tag @AWithZ Official and add #MyH2 — we'll pick 10 people to get a 5-meter roll of nickel-plated strip.
6S2P 21700 long-range pack, my entry for the #21700 power-pack challenge
You only find out how many pitfalls there are once you build your own FPV drone packs: the negative side of tabless 21700s is really current-hungry — I had to push the UF20B to gear 52 to get full penetration.
Paired it with a 40A BMS and measured every cell's internal resistance before welding; max spread 2mΩ. Flew three packs, and the shell wasn't hot when I touched it after landing. Happy.
The recipe is attached to the project. Judges, please go easy on me.
How should I set it for 0.2 copper stacked with 0.12 nickel? My UF20B is at gear 80 and it still won't hold — not a single mark on the copper side. Do I need to add flux first?
Picked up another UK1 — this time it really does go in my pocket when I head out for repairs
Click the knob, press the tip, and you're welding. For house calls fixing shavers and electric toothbrushes I used to haul a big bag; now it's just a UK1 and a roll of nickel strip and I'm out the door.
Still got a little thrill from the unboxing — the box is really nicely made. 0.15 nickel-plated is easy; 0.2 needs gear 70 or higher.
The downside, to be fair: the battery is built in, so after a lot of welds you have to stop and let it recharge.
Built a flashlight that lights up half the street for under 20 yuan
Three 18650s plus an e-bike headlight, with a water pipe for the housing. Welded the nickel strip with the H1 — tiny little thing, handles 0.12 strip with zero effort.
Switched it on outside at night and the neighbors thought someone had left their car headlights on. Hahahaha.
Pic 2 shows the internal wiring, for anyone who wants to copy my homework.
Poll: Which cell do you weld most often these days?
The next Parameters table will be prioritized by vote count. After voting, tell us in the comments which combo you'd most like to see (material × thickness).
Converted a soldering iron to lithium power, pack welded with the UF20B — version 2
The wires in v1 were too thin and got hot, so this time I went with 2S 21700 plus a 30A BMS, and double-layer nickel strip.
This machine is seriously small — it sits in a corner of the bench without taking up space, recharges in a few seconds, and I welded 40 spots in a row without ever having to wait.
Best part when it was done: not a single spot needed re-welding.
Maybe a dumb question: when welding nickel strip on the negative side of a cell, do you need to go two gears higher than on the positive side? I see the pros setting it that way in videos, but nobody says why.
The full 21700 custom pack process, from cell selection to wrapping — filmed it all in one go this time
Capacity grading, matching, welding, fitting the BMS, heat-shrink wrapping — five steps. For the welding step I used the UK1, 0.15 nickel-plated at gear 60, just right for full penetration.
The one thing I most want to say: matching matters ten times more than welding. If cells from the same batch differ by more than 5mΩ in internal resistance, no amount of good welding afterwards will save it.
The most-asked question in the comments, "how much per pack?", is answered too — in step 4 of the project.
Butt-welded 6.0mm steel plates — the P120D is a beast
I'm building a bracket for a turbine afterburner. Tried several machines and none of them could weld 6mm steel plate. Cranked the P120D to gear 999, one loud crack, and the two plates became one piece — can't knock them apart with a hammer.
Industrial-grade stuff is just on another level; even the sound is scary. Wear your hard hat and safety goggles — the spatter is real.
Parameters table update: new lab-tested entries for 0.1 / 0.15 copper
In the lab we welded 30 spots each on the UF20B, UK1 and P60F and took the median of the pull tests. Copper needs flux — without it the welds basically won't hold. This got asked in the comments so many times that we just wrote it into the table.
The table is on the "Parameters" page, filterable by cell × material × thickness.
Getting into FPV drones on a budget — welding my own packs cut the cost in half
Four 4S packs, under 60 apiece. Welding was the easiest step; getting the balance lead wiring order right was what really strained my eyes.
My palms were soaked with sweat on the first flight. Crashed once and broke a prop, but the pack came through fine.
To anyone wanting to get into it: learn spot welding first, and everything after that is just saving money.
7.4V battery for a small fan, two 18650s in series, but after welding it only reads 3.7V. Did I put the nickel strip in the wrong place? I'll add pics tomorrow, just asking first whether this is a common mistake... feeling a bit down.
Finished my universal magnetic base — no more messy workbench
3D-printed shell + strong magnets + a 2S battery pack, welded with the U3 Pro. The step-by-step tutorial is in the project, print files included.
The happiest moment in any DIY build: the last screw goes in and the thing actually works.
12V portable power station pack, my first build, lit up on the first try
18650 in 3S8P, U3 Pro at gear 55, 0.15 nickel-plated strip. I'd watched a dozen-plus tutorials and still didn't dare start. Once I actually did it, it wasn't that scary, and the welds are stronger than I expected.
The moment the light came on at the campsite — totally worth it. Thanks to everyone in the comments who taught me.
Swapped the batteries in the flashlight and the shaver — fixed four things around the house in one afternoon
The H1 is the handiest little tool I've ever used: handheld, rechargeable, fits in a pocket. The cell in the shaver had swollen, so I put in a new one, two welds, put it back together and it buzzed to life — Grandpa's shaver, ten years old, lives again.
The joy of these little fixes — if you know, you know.
Answer beginners' questions in Parameter Lookup and under works; judged by AWithZ staff and creators.
Prizes: +100 points per quality answer · extra 300 points for the monthly Top 10
Deadline: 2026-11-30 · 0 entries so far
Build a 21700 pack (≥4S) with any AWithZ spot welder and submit photos or video of the finished pack plus a recipe card. Judged on weld consistency, construction and safety (BMS, insulation).
Prizes: 1st prize P60F ×1 · 2nd prize UF20B ×2 · 3rd prize welding-pin set ×10
Deadline: 2026-10-18 · 36 entries so far
Brushless motor turned monster fan, part 2 done. Installed + tested in one go, the sound takes off on the spot🔥
The spot welder locks the battery in solid — full throttle, spinning like mad, not budging an inch!
This isn't a fan, it's a 'turbojet engine' strapped to your body…
Take it out in summer — it works better than bringing an AC💨
#MonsterFan #BrushlessMotor #AWithZSpotWelder #UF20BSpotWelder #TechShenanigans
DIY monster fan | Hardcore conversion of a drone brushless motor into a monster fan🔥 Step-by-step tutorial, a spot welder builds super-strong airflow💨, enough wind to take off — the summer cooling wonder!
#AWithZSpotWelder #UF20BSpotWelder #MonsterFan #DroneMotorMod #diy
Avoid the pitfalls in 1 minute! Beginners building a pack — 3 steps solve the core problems: set the series count ➜ set the parallel count ➜ lock in the BMS. With the AWithZ H2-2026 handheld, even a newbie can weld a finished-grade pack and get safely to the end🚗 #AWithZSpotWelder #BatteryMaking #DIY #BeginnerGuide #PitfallGuide
When 'handheld' meets 'supercapacitor', the limits of welding are redefined. AWithZ HF7 — the industry's first handheld capacitor spot welder, fully tested and revealed. #AWithZHF7 #Handheld #CapacitorSpotWelder #Battery
Industry first, major launch! The all-new supercapacitor handheld HF7 spot welder is here! Not every handheld deserves to be called professional. Li-ion pack assembly, tool re-celling, model power mods — all done one-handed. Welds solid, lasts long, tunes precisely, no compromise. Stop settling — get it right in one step. Get in on the launch, keep watching👇
#AWithZSpotWelder #HF7 #HandheldSpotWelder #CapacitorSpotWelder
AWithZ UF20B spot welder | Solid welds on 32140, copper stays put. Still struggling with copper welds that won't hold? The AWithZ UF20B supercapacitor spot welder — output steady as a rock, not fussy about materials. Smart voltage regulation, no more cold welds, consistent weld spots. Punches through 0.15mm copper with ease; tear the copper strip and the weld stays. Hand-built Li-ion packs, done in one go. #32140Cells #AWithZSpotWelder #UF20B #Battery
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WeldWorld is an open platform for user sharing; content does not represent official advice.
Improper battery handling can cause fire, explosion, chemical burns and serious injury. Read the full AWithZ Safety & Usage Guidelines before any lithium battery assembly, spot welding or testing, and before using the community.
Community content is personal experience, not verified by AWithZ; where it conflicts with official documents, the official documents prevail.
Never apply someone else's settings directly; always start at a low level and test on scrap.
Before copying any procedure, go through the self-check list in Part 3 of the guidelines.
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Ep. 37 | Batteries? I can’t repair them, but I can build themProjectsBlindFix
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