Well if there are efficiancy losses in helicals over straight cut than worms are going to lose a lot for sure. screw drives are like helicals on crack. Everything sliding all the time. Maybe the answer though is thinner, better lubricant.
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maybe…
but no regen braking for sure. the power inna worm gear can only go one way. this is why steering mechanisms use worm gears
oh yeah and the brake thing… lol torque transfer is a one way street there
edit: so no free roll either lol ok nvm.
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You definitely can but getting that kind of magnetic field density that the box isn’t massive is gonna be hard, you are basically making a larger motor so at that point just make a 4" diameter direct drive, or have an outrunner motor with the stator only on a portion or the circumfrence
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Yeah if you cut power to the motors you just have max braking power which means none of that shit with not having brakes on a full battery but also if your esc eats it and dies you will get yeeted
i think braking in that situation would require slowing the motors down in a controlled fasion as opposed to using the battery as a load against the street.
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Yea you would need to toy with the current ramping features in the ESC, so your brake and acceleration speed would be directly related to the maximum di/dt you set and the actual current itself becomes less important
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I think this is worth exploring because it involves two of my favorite things: skating and screwing.
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Worm gears suck at efficiency though. Beveled in-line helical seem the best in efficiency and being quiet but very expensive. (I wonder these days with Cnc shops). But I’m waiting for someone to just add two gear reductions with belts and a jackshaft. That’s not that hard I don’t think
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A good single stage worm gear is like 90% efficient, helical bevel is around 96% efficient…so not horrific
Edit: apparently worm gears are only that good at low ratios, my bad
Agreed on all points.
Have had each issue multiple times due to long and separated battery leads- band aid caps help, yes 
shorten and bind battery wires close together if at all possible.
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Wonder what inductance is produced by a welded 18650 pack vs wires but I dare not put my multimeter to the battery
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I’m very curious about this too…can we build a pack in a way that significantly lowers its inductance or is the cell inductance so much larger than the strip and wires we use?
I’ll be testing inductance with some small packs (via my battery analyzer) but I won’t be able to test a big pack for a while, when mine is done.
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so with a battery analyzer you can measure inductance of a battery without blowing it up? I have a multimeter and LCD meter but pretty sure they cant, in fact i think i proved it to myself destroying a multimeter. im going to make a 98 cell welded pack soon and assume being so big it’ll have a lot of inductance and wonder if i need to add some capacitors. Of course i’d like to find its not necessary.
And maybe if I add enough connecting material between the cells it will reduce the inductance and resistance. two at once.
or can i add enough resistors in series with the battery to possibly get the voltage and current flow so low i could use a multimeter to test inductance?
@hummieee @ZachTetra how would you guys know what kind(rating) of cap to put in line with the esc? Would you first have to calculate the inductance building up? Or just pick something within the relative voltage and frequency?
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Yes, the BK Precision BA6010 does that (a long with a lot of other measurements), up to 60V.
Reducing the resistance of what you connect the cells with often reduces the inductance (think short and fat). The arrangement of the wires directly affects inductance but I don’t know how much of the pack’s inductance is due to just the cells and how much is due to the wiring…yet.
I don’t think that adding capacitance to the pack is necessary as you can most effectively do that at the ESC end of the battery wires.
Sorry, I don’t know what you’d need to do to safely test pack inductance with the gear you have. Any resistance in series with the pack just adds inductance too.
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Can some one define long and short
Is having the pos and neg opasit sides of the pack as some people suggest to minimise the potenchal difference of Neighbouring cells then classing as a long?
Is any MTB with battery’s in the middle and ESC at the back classed as long battery leads?
It depends on the wire, I think if you double the length or double the current you need to double the width of the copper
Probably 4’ total (this includes going through the cells) from esc positive to esc negative is where you need to think about it but it really depends
You need a variety, small caps pick up the start of the spike and big caps take up the brunt of it, but I don’t know how many farad’s you want, but more is better and they need to be rated for a lot more voltage than the battery has (you want them to have ‘head room’ at your battery voltage if that makes any sense)
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