Take my money 
So cracks aren’t likey on the newer versions? Those are all PLA?
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It’s looking pretty good dude.
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fits like a glove. but i see 3 cracks, left side 3rd from the buttom.
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the battery packs look clean and easily replace-able should any cell fails. keeping a close eye on this thread
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Looks good. How are you going to secure the modules to the cutout?
Petg. The closer 4 on the right is the newer ones with less fillet. For securing, I have plans. Haven’t had it out yet but it will be nice.
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This is what you need https://www.amazon.com/gp/product/B0779N142T for securing nicely in the plastic.
Also, you had asked about the pack dimension(along length of cell), well mine should be 71 according to design, but is 71.5 in reality. Since the slot in hummie’s deck is 74mm wide you will have enough space to accommodate these hex screws. The height of module is 22mm. Distance between cells is 18.3(because of N.E.S.E tabs)
Have you considered printing the raised part in TPU, as a separate part? That way the braided part has some springiness to it when contacting the cell terminals? Did I make sense? Else I can cad it up.
What BMS are you using?
Bestech d140 12s from esk8life. Make sure you tap a pilot hole before using those wood screws on heard wood.
Haven’t been posting lately so here’s some pictures.
Finally going to test the copper sleeves this Friday meanwhile I have this 12s pack (made with couple versions of holders, cuss I don’t want them to go to waste) all wired up. The final version is the ones with long nylon standoffs.
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Dude. That looks great. The divide between the cutouts, channels the bms wires nicely.
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Very neat build. No wire hell.
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Yeah I was pretty amazed too. Only temporary taped down tho idk how I should secure them semi permanently. Maybe I should super glue the wires together.
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Electrical silicone?
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Wonder if you could print holders as well that clip onto the wires running along the middle. Though tape is fastest and cheapest. Awesome work! They look better every update!
Cant wait till you can start producing these for others 
maybe use these with zip ties https://www.amazon.co.uk/Stonges-Adhesive-Cable-Mounts-Durable/dp/B01HR45KBA
Consider me camped out in front of your house in line waiting for one. I’ll be looking forward to whatever you use for an enclosure for your hummie deck as well.
as promised I did a load test with those tinned braided copper. it works great. did 60A for a few minutes and only warmed up to 30-40C whereas the batteries went to 50C. found out there are different thickness of braid afterward but its getting to late to post everything so I’ll make an update tmr.
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yay for updates! I suppose going for thicker braids would be generally safer?
As promise there’s the big update:
Didn’t know that there are different thickness of copper braid. I bought some 1.2mm and 0.3mm thick braid.
- 0.3mm - Seller list it as rated for 40A (right)
- 1.2mm - no rating available (left)
Since the thicker braid came first, I did measurement changes tailor to it so when the nylon standoff meets the cell holder on both sides it has a right amount of compression and not damage the 3d print.
you can kind of see the circular deformation at the top formed by the terminal buttons. This way there’s enough compression on the battery terminals without weakening the integrity of the cell
Testing with the thicker braid was pretty straight forward. This test is mainly for measuring the temperature of the copper braid during high continuous discharge to ensure it doesnt get too hot for PETG (80C glass temperature). The test was conducted on a 4p Samsung 30Q pack with thick copper braid (fully charged to 4.2V) with 10 gauge wire soldered to the ends of the braid. Using a 240W DC load, I drew constant current 20A, 40A, 60A (maximum of the DC load) for a few minutes while monitoring the temperature of the braid, closest to the opening of the cell holder and the batteries, with a IR thermometer gun.
The result is very optimistic. At the end of 60A constant current draw, Battery temperature was at 50C, while the braid only reached about ~40C. I also did a good old touch test to confirm that the braid was colder than the batteries. This video didnt capture everything but you will get the gist of it
Since the measurements are tailor to the thicker braid and it pass the test by very large margin. I will keep the current version and test the thinner braid later when I have time.
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