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[DIY] AWithZ U3 Pro spot welder: a home-made spare battery for a power drill, 21700 pack welding, efficient welding with half the effort
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![[DIY] AWithZ U3 Pro spot welder: a home-made spare battery for a power drill, 21700 pack welding, efficient welding with half the effort · 1](https://cdn.awithz.com/assets/_derived/w480/community/works/d086/cover.webp?v=5384d0a0.q82 "Video")
Bill of materials
Welder, accessories, consumables and parts used in this build; quantities and specs are editable Download BOMAWithZ official
Third-party partsFrom the creator’s parts list, grouped by category; links to third-party stores
21700 battery packCell
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Third-party
Description
[DIY] AWithZ U3 Pro spot welder — a home-made spare battery for a power drill, 21700 pack welding, efficient welding, twice the result for half the effort! #Compact #WeldingEquipment #ElectronicsHobbyist #GoodFinds #ApplianceRepair
Bill of materials
| 21700 battery pack |
Li-ion safety
DIY lithium packs can catch fire: check cells for shorts before welding, always add a BMS, never skip insulation and fusing on high-current builds.
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