Come on dude... 500J spark -> instant 1M subs 😉

That stringing on your print is driving me crazy lol

"Thinking is.. big brain" - Bardwell 2025

I heard bardwell's discord notification & was like  'people like me !'

Yeah that's a PROPER spot welder. Respect! I want one but I don't build enough packs....

Tip: buy longer balance leads. A pack of 10 Balance leads for 4s cost like 2$ shipped, and they come in different lengths, like 10/15/20/30 cm. Price difference is just a few cents. Cutting too long cables is always easier than work around too short ones. we are talking 20 cent vs 25 cent per battery pack here

Im sensing a new t shirt, "thinking is.... big brain!"

That's a defibrillator, with a spot welding attachment! 😮😊

Joshua, on that king of stringing on 3d prints, just use hot air gun or flame from lighter, it will just disappear. (just like you would on heat shrinking tube)

Good job getting a kweld and getting into building packs. I'd reccomend the following.

Round the sharp corners off the nickel on the positive terminal side at minimum.

Try to to cross balance leads. Where they do have to cross isolate them from each other with an additional abrasion resistant material like fisch paper.

Epoxying or gluing cells together would be better than foam tape as it will hold them more rigidly and transmit less vibrations directly to the spot welds.

Select appropriate wire gauge, nickel thickness, copper thickness for the intended loads.

Some of the cells out there today will surpass thin nickel strips and can melt them

For typical 21700 cells, you want to avoid spot welding within a 3mm circle of the center of the cell.  For tabless cells you want to avoid 6mm circle from the center.  This is where the current collector is internally attached to the can and it should be avoided if possible.

You really should make sure that the strip covers the whole terminal so you can get 2 or 3 sets of spot welds.  Not only does it lower IR, but it's also redundancy should the spotwelds fail over time from high vibrations.

The negative electrode always tends create a weaker weld. A lot of people like to swap electrodes and perform the weld again.  Or another similar method.

Should have routed those balance leads through the end frames rather than around them. Would be cleaner. But would have to use your noodle a bit more..

This is hilarious...I actually watched your first video on this late last night just before this came out bahaha Great timing

Talk about perfeft timing!
I was literally researching hobby spot welders this week :)

Hey JB!! Thanks so much for the updated video!! It’s so good to see you again, and to see you finally broke 400k!!! That’s awesome, but it seems like maybe I don’t see you as often anymore??? Maybe it’s the algorithm not showing me your content as much… but it’s good to see you!
Especially this pack building video! Just in time for my next pack build too!! Fpv has been difficult lately due to import tariffs and the ability to find DJI video system parts but I’ll eventually go to analog if I have to! You’ve helped me since the start and if I need to learn analog I’ll just go watch your vids from 5 or 10 years ago lol! Have a good one bud!

Thank you Joshua Bardwell for your wonderful tutorials! I have just built my first 14S16P pack following your first tutorial, and it's very good except the fact that my charger crashes out when I put it in, but I have just charged it by plugging the two main contacts directly into 50v dc for short periods of time instead, so no problem there! Love your videos!

Starting to get into custom packs as well! Great timing on this vid for me

Josh. I’m not being Picky or anything or trying to dis your work by any means. But them balance leads should have some isolation between them and the cells as they could short. And the wires not crossing each other. If your serious about building battery look up the Glitter 811h spotwelder I’m using it to build a 24s12 monster. The biggest I’ve built to date.  Keep up the good work bro. We all love learning 👍🏽😊

I have AWithZ UF20B, costed me around 115 USD. This is a beast spot welder, which uses Farad capacitor and plugs into the 110/220v socket. Works extremely well (compared to my old BIFRC DH20 pro. Can handle 0.3 pure nickel strip easily. It has a nice case with color display etc, feels like very finished product. You can use pedal, you can use auto mode, you can also use small button on the welding leads.

Perfect timing, I've been looking for one, lol

I’ve spent most of my 42 years on my grandfather’s farm and somehow became the go-to welder for everyone in a 10-mile radius. Thankfully, everything I work on is much thicker than this! Honestly, the thought of trying to weld something that unbelievably thin makes me as anxious as I was at 9 years old just learning how to strike an arc.