I assume those quantities are just some random values since multiple sellers tend to have “1000” of every possible item, which then drop to 999 when one is bought and so on. I imagine the shop interface has a field for stock and they just jot down something. This is why it’s interesting to see when someone opens one of the 800W ones, if the stator is actually any longer. I sure hope that’s the case.
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Here’s the thing on grass 
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That looks pretty good doesn’t it? Are you still on the 10S battery?
I tried a ride on the grass tonight. Couldn’t find a driveable field with such high grass as in your movie however. I am running Hoverboard motors with dual Focboxes and 12s battery made from old hoverboard batteries (the batteries seem to be the culprit in my setup).
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It’s decent, mostly limited by my skill at riding 
I’m on 12S now too, but at such low speed there’s no difference as it’ll reach the 85A phase current anyway.
I imagine you don’t have any vesc heat related issues as the load is split between the two of them. I need to improve cooling on my single focbox if I plan on doing any more extended grass riding, it’s getting quite close to the thermal limit.
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How do you even improve cooling on a focbox? External fan or something like that?
Connect the FOCBOX aluminum back piece to the frame or some way to get heat to the outside
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Yep, I 'll need to replace the current plastic holder with one milled out of aluminum which makes contact with the aluminum footpad plate. Currently no access to a milling machine sadly.
hold on. Never had an actual focbox. I allways though they were metal cased
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The bottom half is metal and the top half is plastic.
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It is metal, but that doesn’t help all that much when it’s in an insulated plastic box, nowhere for the heat to go. It needs to be screwed onto something thermally conductive which I should have done from the start 
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Yeah make sense.
Would thermal pasting it make any difference?
(I’m gathering ideas for when my time comes)
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@Jopj die you end up with that cheap charge only BMS from AliExpress? Can you show me how you wired it up. I feel like a dork when reading those manufacturer schematics.
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Sure but it needs to be pasted into something thermally conductive in the first place, pasting it into the plastic holder would do no good. Paste between the focbox and the (future) metal mount, as well as that mount and the footpad plate is a must.
It’s not optimal since there’s a lot of solid metal between the heat source (vesc) and sink (footplate) but it should be enough.
Yeah, that’s in my battery while I figure out my own BMS design.
Beware: it does not balance the cells so you need to periodically check & balance them yourself if you use it
This is how it’s wired, except “load -” goes directly to battery - and not to the bms to bypass it in discharge. The balance connector starts from the negative side of battery, and any extra pins (for less than 13s battery) are connected together to the highest cell positive. So in my 12s case, pins “12” and “B+” both go to the top cell positive. For a 10s battery, it would be 10, 11, 12 and b+ that go to top cell positive.
This is how it looks like in the battery, although I doubt that’s much help to you as it’s so cramped in there. The extra connector is for those cells going to the second half of the battery so that the halves can be separated from eachother
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I don’t think this is the correct way to wire this BMS. If a BMS has both C- and P-, then P- is for the load and C- is for the charger. If it doesn’t have C-, then both connect to P-.
Maybe this is closer to what you described
This is mostly for folks reading this later
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Yes, that’s the “load - goes directly to the battery -” bit, I should have updated the image rather than just explaining it. Of note is that the manufacturer specifically says to avoid using P- for an unknown reason, maybe the PCB has some error regarding it. The discharge current is too low for our uses anyway.
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That’s a good question. @Jopj do your lights change based on direction, or are they hardwired red on one side, and white on the other?
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I don’t have anything in the rear, the front lightbar turns off while riding and only the power and orientation debug light stay on. It is very easy to program light changes based on direction with an external controller, and for those using the balance app it would just be an Arduino or similar which reads motor velocity over serial and blinks some leds based on that.
I was thinking of using ws2812 strips, but I don’t have a 5v source powerful enough to drive those, I don’t want to put any more load on the VESC 5V source.
One could have all kinds of patterns and pulses, or just “if(vesc.data.rpm > 0) {f=w; r=r;} else {f=r; r=w;}” 
The way I would do it: Get this library on an Arduino, test it by having it light up it’s led based on motor direction, then add whichever type of lights you want (with their power supply), and have the arduino control those instead.
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Just briefly touched 29 kph! That’s when pushback kicks in with my current settings with nearly full 12s pack and the delta-modified Phub. I’m still pretty antsy about this speed, but pretty comfortable cruising at ~20-25 along some gravel roads around where I live.
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To tackle the newfound VESC overheating issue I’m planning on an aluminum block which is screwed and thermalpasted to the Focbox’s heatsink and comes through the mounting plate as well as the cover…
And is itself screwed and thermalpasted to the bottom aluminum plate with some added ribs for good measure.
There’s going to be 15.5mm of solid aluminum between where the heat is generated and dissipated so not exactly optimal, but bound to be better than how it is now. It’s gonna be less waterproof also, but it’s a compromise I’ll take. 
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