That doesn’t really work unless the epoxy itself is really thick, it will just seep out.
[laughs in JB-Weld]
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Yes, to clarify, I was referring to the bending rigidity of the vertical nickel strip, not the shear stiffness of the weld joint. Those joints can be approximated as undeformable in comparison to the structures around them
Partially. You’re close though 
the correct concept here isn’t exactly “contact area”, it’s “2nd moment of area”, which is like a weighted average of area depending on how far away that area is from the center of the bending beam
Milled fibreglass definitely thickens up epoxy. Not sure about the chopped stuff tho
I used 6mm chops and while they make a thick paste during mixing, if you use thin epoxy most of it will just seep out after application.
That’s the data I was missing. That perfectly answers my question.
Yep, I understand all that 
My concern is specifically about this:
If the purpose of the plastic frame is to take load off the welds, then I am skeptical of the frame being stiff enough to make a significant difference. If the frame is just there to hold the cells while a glue or epoxy cures, and the stiffness is therefore coming from the glue, then that’s a different matter.
I could be totally wrong here, that’s just my intuition. You did ask for feedback, after all 
Yeah, that’s what I was referring to as well. Sorry for not communicating my thoughts more clearly. I think we are all on the same page about what your JBweld is supposed to be doing. My post was simply about Cian’s plastic frame.
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Only if you apply it to the bare cell though, and assume perfect bonding. The shrink wrap make things more complicated I think.
Right, I can’t comment on how stiff that plastic frame is. I don’t know the mechanical properties or the cross-section of it.
It certainly does complicate things, in that it can be pulled off of the cell in and therefore has no tensile stiffness. The bond strength doesn’t actually affect the material stiffness, however.
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I would be really uncomfortable with using cells without wraps, although for properly constructed p-groups that would probably a non-issue…
It’s still a massive overkill though, especially when flexible series connections are basically standard nowadays. 
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Can I just rip out the old broken cells out of my old evolve gtr battery and put in new ones without there being any calibration issue or anything?
Not really
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What do I have to learn before this reads like English?
Haha the field is called Statics (as opposed to dynamics), and I was specifically referring to beam theory. It’s accessible if you’re comfortable already with algebra. Calculus is helpful, but isn’t required for the simple stuff.
“Modulus” is the fancy term for the stiffness of a material. I was basically claiming that the stiffness of a nickel/epoxy p-group is based on the stiffness of each material, compounded by how much of each type is present
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Where do I enroll for the school of fuckin madmen? I’d like be be well informed about the terminology used to describe the forces that will be applied when I fling myself off a board at 35mph
(Okay but I do genuinely appreciate the info, thanks man)
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That’s called the school of hard knocks lol. Half the stuff I build doesn’t work, if you want to make crazy things you start by pushing out of your comfort zone one bit at a time 
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Here’s my current battery build, to replace the dead lead acid battery in a car jump-starter.
Headway 38120 8AH LiFePO4 cells, 200A discharge each, in a 4s2p configuration.
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I guess you are ok with this now 