dnmun wrote:this split pin approach was a great idea that started with evb on the other thread, i just think out loud, but this is so simple now, reliable connections, easy to go back and replace defective cells.
thanks for the excellent documentation. Everyone should follow your example of providing such detailed photos & info.
A few questions:
1) So, once you've welded the tabs is there still plenty of space left to cut this welded section off to do a repair by replacing one of the welded cells with a new cell? If yes, then will you be able to undo & unfold everything reusing the one good cell that you had to cut its welded section off of too?
2) What is the dimension of just the tab area that can be worked on or folded that sticks up?
3) Can you work safely right down to the edge of the cell where the tab begins to stick out, or what would be the "safety gap" or space buffer to use?
4) What is the minimum cost for a spot welder to do this specific job as good as your spot welder can do this now? Recommendations?
5) How are you sanding & prepping the tabs to remove the protective film surface coating?
Thanks DeVries! I think if you read my earlier posts in the spot-welding thread it will fill in the gaps, but here are answers:
1) Yes, every single one of my crimp and spot welds since 2010 have been reversible. It takes time and patience to unfold, but I have done it. With spot welding, you have to cut off the welded section; with cotter pins, that section is smaller.
2) the part you see, I've never found a need to measure it, nor could I use this measurements in practice. Each roll is different, depending how you placed you cotter pin, how tight you fold it etc. There are pictures from multiple posts showing diffferent techniques to give you an idea.
3) I use a safety gap that will let me get heat shrink under the roll, I eyeball the distance.
4) Quote on Spot welder selection: "This is Harbor Freights $160 "115v spot-welder" I could have purchased the same product on ebay for $35 less, but I wanted to be able to return it." Now that I know it works, I would have saved money and purchased the identical eBay version.
5) not aware of any protective coating, just oxidation, which I would recommended buffing out to your preferences.