All the power
All the time
All the turn…
All the kgs 
I can ponder this for sure… i’d need to tail/nose mount the escs, but i’m sure that can be done…
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101 teef for the hunting tooth ratio 
I think i wanna print the teeth section with gf nylon and the flange/adapter plate will be waterjet cut alu probably.
There is also a little adapter on the back of that plate to help it locate and space it correctly to the hub that i’ll also print with gf nylon, it’ll have the seven bolts through it so should be plenty strong enough.
Test print with petg happening now 
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I think I’d actually prefer regular nylon for the teeth. Gf/cf are quite abrasive so I’d be worried about wearing through the belts faster with that, not sure if it’s a valid concern or not. But also regular nylon is plenty strong already
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I mainly just wanted the gf for the extra strength to use for other parts as well. I agree that regular nylon would probably be better for the teeth. Maybe i’ll just get both types!
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Many say that carbon-fiber-reinforced nylon is the best material for functional, load-bearing parts. I would also coat it with epoxy resin.
Yeah i’d definitely be worried about the cf abrasive properties on the belt though, straight nylon should be plenty strong enough and should run smoother too.
First pass at this went really well, tooth profile looks awesome against a belt even though i don’t have one big enough to go all the way around
Need to tighten up the little nubs that insert into the hub and bring it in a little closer to the tire, but other than that i think it should be pretty good!
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Bummer. Not quite enough for 2x 12s13p 
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Finally, you’ll have good reason to play with that beast of an AwithZ P120D spot welder.
Interested to read your opinion as you experiment.
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to be fair I don’t think i’m gonna do a whole lot of experimenting with the welder as such… I’ll fuck around for as long as i have to to get reliable results with the 0.3 copper I have and then send it from there. I have a reasonable little stash of test cells, enough to get my settings going well, then i’ll tweak from there on the BAK cells, hoping there’s not too much difference between weld quality/cells.
I will certainly post the progress and the fuckery here though!
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Understood. I am just curious as to your experienced impressions of the p120d and your transition to copper from what you are used to
I felt like 0.2mm copper by itself tore away from the weld too easily with my much less powerful AwithZ p20b.
The increase in power required to weld 0.25mm copper compared to 0.2mm was much higher than anticipated, but tearing it away from the solid weld also took a lot more force. I think the heat affected zone near the weld annealed the cold rolled half hard copper, and that extra 0.05mm seemed to double the force required to tear the copper away from the weld.
I was able to weld 0.3mm copper under 0.2mm Nickel plated steel at gear ~940, with the flux, but both busbars had the slits to weld across. This was for a DIY 10 cell 21700 Makita battery. Nelvick @DIY500AMP.COM laser cut the 0.3mm busbars for me based on a photo and a few caliper measurements. I used BAK45D and the battery is a beast which makes the stock Makita batteries seem pathetic in comparison.
I know you don’t want to use flux, or sandwich, and will have more than enough power to be able to skip it, but perhaps have some 0.15mm stainless on hand anyway.
The tear off strength when capped with SS is so much higher in my experience, and the welder power required is significantly less which might be beneficial to cell longevity, and reduce the risk of blowing holes in the anode.
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This is going to be such a unique build. Are you planning to flip the hangers to reduce the wheel bite?
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I will fuck around a little bit i suppose. Will see how it goes raw dogging the 0.3 copper by itself and with flux, but will most likely go with stainless caps. Just ordered a roll of 15mm x 0.2 stainless off aliexpress. I think keeping the weld energy to a minimum is a safe approach 
I wasn’t planning on that and @Titoxd1000 has recommended against it so I probably won’t.
I was planning to extend the truck mounting holes out with deck extensions, yet to be designed.
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I wonder why it’s not a good idea with the extended baseplate, which I think you have on this build? There must be something about the design. Otherwise lots of others are running flipped hangers.
I have flipped hangers and redrilled truck mounting holes on my Bro deck to prevent wheel bite with 9” pnumatics and couldn’t be happier.
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Yeah i think the extended baseplate is just a standard thing now.
i haven’t really had a play around with the hangers but it might be worth looking into.
from the quick little play i had with it when i first put the wheels on, it seemed like i would need to extend the wheelbase a fair bit… i may end up doing a bit of both!
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The extended baseplate is pretty much already flipped. Meaning the original baseplate had a 15mm or so offset with the hanger outward. The extended baseplate has a 15mm or so offset with the hanger inward. Inward hanger gives about 20mm additional ground clearance than the original. Flipping the hanger outward on the extended baseplate would give a offset of 50mm or so, the extended baseplate was not really intended to deal with all that leverage.
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Ok, i’ll run with that.
As for the height difference front to back, i’d rather keep the extensions as minimal as possible but i’m happy to add a riser to accommodate the height difference.
Excited to build this pack. For now i’m still fucking around with my cell holder design, trying to get the tolerances just right.
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Ok it took a bit of doing but i’m pretty happy with this! Just gotta check if i have any more length in the segments to thicken the ‘lids’ up a little bit to house the screw heads a little better. If i don’t have enough space i’ll see if i can’t just get smaller screws.
There’s a tiny gap designed into it to let the copper come out and fold over, the intention of the lids is to try and hold the copper firmly before the fold to prevent any flex from reaching the welds.
Once everything is soldered up i’ll also tape the copper tab and wire connections down to try and secure that tab as best I can.
I’m thinking that I could silicone the lids before installing and somehow silicone around the copper gap as well and these packs could almost be waterproof, although i’m concerned that the permeability of the print itself could present an issue there.
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Wow, thanks for sharing this with us. I hope you’ll share your STL files with us later on. May I ask—it looks like an 8P configuration to me; why are there two extra cells at the end? Personally, I’d think it would be cool to have cases like that which you can bolt directly onto the board from below, module by module.
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I can share the files for sure but they’re really only going to be relevant to this exact enclosure and battery configuration… and you’ll have to deal with my horrific fusion workflow if you want to modify 
The battery will be 18s8p split over 8 enclosure segments.. 16s8p fits nicely in full groups, but the remaining 2 groups are split over 4 segments each. It was the easiest way to fit 18s8p into this enclosure.
The yellow connections are parallel connections… hope that makes sense
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