If its stringing, the teps are too high. Lower by 5C then back up a tad
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Petg is very sticky so it tends to string a lot. I would lower temp by 5 at a time and teak your retraction setting. Also printing 40mm/s is the fastest I would go.
Are you guys using fish paper rings with the N.E.S.E tabs? Would it increase the gap too much to make contact with the positive terminal?
it should work (the tabs from Agnius are with pins for the contact that are higher than fish paper) but its not necessary due to the construction of the modules. He even showed them working with removed cell wrapping. (I wouldnt do that though :))
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That sounds scary. It should work, but still scary 
if u need more thrill 
I have put about 300km on the original NESE and also without any fishpaper between the cells or around the positive terminal. Iâll soon print the updated box thatâs has a divider in between for safety of mind. But @JonathanLau1983, the fish paper rings is absolutely not a necessity because of the raised tabs.
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Thanks, I was thinking that, however as I will be removing the cells for flights it does mean the cells will be moved in an out more than a normal build. My only concern would be wear on the heat shrink due to this. I am designing my battery case with this in mind so the positive ends have to be inserted first, and negative end slid down.
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I have probably removed and installed it 10 times or so. I am wary of that potential problem, so I make sure to push it in vertically and while taking out I make the modules be upside down and gently-slam(hope you understand) the board on the ground. All the cells pop out in a couple of tries and land softly on a towel.
@agniusm, whatâs your recommendation for frequent installation and removal of cells? I am guessing your modules are not typically designed for that.
Its not meant for that. Occasional bad cell replacement is whats it for. You can take 100wh on the plane so better have module release system and have separate <100wh modules.
Just a teaser, summer(mid to late) might bring 21700 (20700 compatible) modules and hardware.
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21700 please!
Nice! If moulds havenât already been made, please do consider to have a little more gap between the cells so that itâs not skin to skin and a wider gap between the 2S groups built into the tabs. 
It will be skin to skin as it does not matter in P groups. I have sold too many to fault them there. Having said that, for people who are concerned (like you ) 20700 cell will give you that 0.65mm gap peace of mind 
For the S modules it will work the same way as with 18650. I think its enough of a gap for isolating groups from shorts.
The key here is to have modules as compact as they can be while retaining the ease of builability with single phillips scredriwer
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I think he meant specifically the tabs. The divider width makes the tab a bit off on one side, eg for a 2s3P like mine the 6p compression tab you just send me should be a 2 groups of three with a little wider gap in between. its working though, but if its possible to change them its better.
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If i make it, i need to make it for all the P groups, that means a bigger gap on 3 cells, after 2P, 3P and 4P. If its 0.9mm that is 2.7mm longer modules. The nipples are smaller that positive end of the cell so there is no electrical or mechanical issue there, just visual if you are not keen on the offset cells. I think going 20700 is a good compromise if you are concerned.
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Quick question on these. When assembling the pack, which order is appropriate to connect everything? Balance leads plugged in to BMS first or battery negative attached first?
Depends on BMS or PCM. The ones i use was balance connector first. I ,dont think it matters though. Balance connector always has B- as first pin. So balance connector B- (sometimes B1) has continuity with BMS/PCM battery negative power pole.
Here is a comparison between 18650 8P and 21700 8P modules This summer might bring new modules. 21700 and 20700 has no no solder solution so i am investing in tooling to get this covered. Here are some teaser photos on size comparison between 21700 and 18650:
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hmm yes⌠the left one is definelty better⌠but not good. Maybe i just have to high requirements to PET-G. Tried A bit PET on the weekend. Its ok, but for ME the material is not that good printable. The results in ABS are just better. At least for me.
But if i find some time, i ll give it another try.
My ABS are just perfect at the moment. So its not nesserary to change.
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looks like a watermelon. love it
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Use no pigment PETG. Additives make it worse in my experience. Also use a silicone sock and a thin layer of silicone sealant on the exposed nozzle. Bam! No sticking or dragging. Final thing is that the nozzle shouldnât be as close to the build plate as you have with PLA. This results in the molten filament curling up and causing problem when the next layer is being laid.
This how my prints look.
I have a beautiful benchy too, that I printed after silicone sock and silicone sealant mod. Iâll post it here when I go home.
And look at this abomination printed with black PETG. No matter what I did, I couldnât print well with it.
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