Ep. 127 | Skip one meal and you can own a handheld spot welder — build your own packs at home

AWithZ H2 handheld welder unboxing: pen-sized, color screen, Type-C, gears 1–10; gear 8 punches straight through thin sheet metal, welds can’t be pulled apart; demo on 4 × 18650

The creator bought the latest AWithZ H2 handheld welder to build his own packs. In the box are two parts boxes: 2 spare welding pins + a Type-C charging cable; practice nickel-plated steel strip; a manual and a card (read carefully, mind the precautions). Safety reminder: welders and lithium batteries are both somewhat dangerous, wear goggles. The body is pen-sized, with a built-in lithium battery, Type-C charging and a color screen showing the parameters; two welding pins; a Type-C port and two buttons at the back (the select key combines several functions), model and power on the rear label. Principle: a momentary heavy current through the resistance heats the metal instantly so it fuses — unlike a soldering iron; the nickel-plated steel strip on 18650/21700 cells takes solder badly, and lithium cells hate heat. Long-press to power on; the color screen shows weld mode, trigger time, gear and preheat time; short-press to step through settings, the up key enters the menu; beginners should keep the factory defaults; gears 1–10 map to different thicknesses, and gear 8 is more than enough for the thin sheet in hand — it punches through. Demo: the two pins touch the sheet for an instant — a flash of sparks; wood underneath gets a burn mark and smoke; the weld is flat and takes no room, and pulling hard won’t separate it; then a demo on 4 × 18650, and if a weld is not solid enough, add a few more.

Outcome

Steps7 steps · click a frame to jump

1. 
   1. Unboxing: spare pins, Type-C cable, practice nickel-plated strip, manual

   AWithZ H2 latest model; two parts boxes: two spare welding pins + a Type-C charging cable; a set of practice nickel-plated steel strip; read the manual and card carefully, they include the precautions.

   00:00 – 00:54
2. 
   2. Safety note and the handheld form

   Welders and lithium batteries are both fairly dangerous, work safely and wear goggles; the body is the size of a pen grip.

   00:54 – 01:20
3. 
   3. Built-in Li-ion, Type-C, color screen, two pins; how it works

   Built-in lithium battery, Type-C charging, color screen for reading parameters at a glance, simple settings; the two welding pins are the main body on the left; a momentary heavy current through the resistance heats the metal instantly so it fuses, unlike a soldering iron.

   01:20 – 02:00
4. 
   4. Why lithium cells get spot-welded: nickel-plated tabs take solder badly and hate heat

   Welders are most often used to weld nickel-plated steel tabs onto 18650/21700 cells — a soldering iron struggles to tin them; lithium cells have a temperature safety line and overheating causes trouble, hence the ultra-fast, ultra-flat spot weld; Type-C port + two buttons at the back (the select key combines functions), model and power on the rear; enough for home / DIY use.

   02:00 – 02:50
5. 
   5. Power-on and menu: weld mode / trigger time / gear / preheat; gears 1–10

   Long-press to power on, the color screen shows weld mode, trigger time and gear; short-press to set each item (preheat time, trigger time…), the selected one turns white, the up key enters the menu for repeated settings; beginners can just use the factory defaults; gears 1–10 map to different thicknesses, gear 8 is more than enough for the thin sheet in hand and punches clean through.

   02:50 – 03:54
6. 
   6. Test weld on sheet metal: instant punch-through, flat weld, won’t pull apart

   The two pins touch the workpiece for an instant and it welds; wood underneath gets a burn mark and smoke; with the power high the thin sheet is punched through instantly; the weld is flatter than solder and takes no room; pulling hard won’t separate it, as if the two pieces fused into one.

   03:54 – 05:12
7. 
   7. Demo on 4 × 18650; add more welds if not solid

   Say you weld 4 × 18650 together — place the strip and it punches through in a flash of sparks; if a weld is not solid enough, add a few more; the welder has plenty more functions for DIY players to explore.

   05:12 – 05:47

Bill of materials

Creator’s tips

• Beginners should start with the factory default parameters 03:31
• If a weld is not solid enough, add a few more to deepen it 05:33
• The pins trigger on momentary contact; don’t rest the work on wood (it burns and smokes) 04:18

Pitfalls

• With the power turned up, thin sheet metal gets punched through instantly 03:46

Li-ion safety

• Welders and lithium batteries are both dangerous; wear goggles 00:54
• Lithium cells hate heat; prolonged soldering-iron heating invites trouble 02:13

Quotes

Cost & time