Modifying prebuilt junk, in stages, to be less junk like.

my wife would skin me alive

Haha, yeah…

Fortunately, with ten eboards lying around, fifty or so salvaged e-scooter batteries, a bunch of loose cells, tins of acetone, resins, oils, chainsaw petrol etc… mines pretty used to it! Worse is that it’s all coming into the house to allow for knocking down the old garage.

Fuses, fibreglass, and substantial airtight enclosures and I’m just hoping nothing ever bad happens. I am careful with my builds.

I’ve not had a battery fire at least, unlike some I know who didn’t respect that a zero volt Li-ion means recycling time, despite being warned.

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I was looking to buy Arctic Silver thermal epoxy a while back. But didnt.

Cant remember exactly why.

But just now used JBWeld, filling in the copper grid, and SS screws to align and pull finned aluminum heatsink tight.

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I wired up my male 11 pin JST 2.0, to a 7Pin and 5 Pin JST2.54mm females, and cut and peeled back my shrinkwrap and some kapton tape, in order to unplug the balance connector from Daly dumb BMS

Now I can plug in my balance lead into two 7 cell ‘Capacity Controllers’ and scroll easily through Pgroup voltages.

Cells 1 through 6 on one meter, 7 through 10 on the other meter.

The two meters disagree slightly, but after about 600 miles on this 10s2p battery since January, there is a max 32mV disparity.

I have not done many 4.18v+ charges, and only a few were holding 42v for a few hours. But there was a 12 hour unintended overnight 42v hold a few weeks back.

This BMS supposedly only balances above 4.18v per cell.

I was not able to detect any BMS heating when holding it above 4.18v, back in January, and just injected 4.2v into the then 300MV low cells.(8&9), and they stayed incredibly well balanced through first desktop discharge before shrinkwrapping.

The remote’s odometer had about 500 miles on it when ESC randomly began shutting down requiring a power cycling to continue. I suspect I put close to 200 miles on the other Lingyi. 90% of miles are accumulated towing Fiona in her land or water chariots.

So 32mV difference after somewhere between 600 and 700 miles of towing on flatlands with hub motors, seems pretty good to me.

Both meters agree Pgroup 5 is the ~30mV low one, So I’ll likely bring it upto 4.075, inline with the others, Kapton it closed, and return this battery to the enclosure.

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The 12mph max 7S Diagonal Mini, with its dual145mm wide single drive hub trucks, has been doing no less than 10 miles per day for 8+ days now.

Since it is so slow, but nimble, when no cars are around, I take the whole road, and push the ~70mm urethane to its hissing limits with high amplitude, high frequency carving sessions, until my legs turn to rubber, and Fiona is barked out, or the battery is done.

I was hoping to put 80mm m1 inboard hub motors on this board, powered by a 10s1p P42a, but the narrow deck needs narrow trucks, and the calibers trucks I have which fit the M1 hubs have a significantly wider track width.
Too wide.

I want to keep this board, light and nimble, ans semi stealthy, with narrow trucks.

I am not sure how to proceed.

My copper heatsink which has secured three different ESC’s now, has a lot more surface area than before, with deep aluminum fins reaching deep, for airflow.

It is still nearly a perfect seal, without using a sealant.

One of these days, the volan green enclosure, will be painted flat black.

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Mor heatsink mo betta. I have a tendency to go a little overboard with my heatsinks and this is just good :grin:

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I hope it is overkill.

When the copper was first exposed to airflow I was surprised how hot it was getting via finger test.

Getting a reading with IR temp gun was not happening on shiny surface.

When I sharpied the grid black, it made little difference, but when the copper that she sharpie couldnt reach oxidized, it started almost reading accurately. It would say 127f when flat black hub motors were 147f, and fingers said they were about the same.

I think the hundreds of miles accumulated when heatsink was not exposed to exterior airflow, was a major contributing factor to the ESC’s demise

Eager to go fast again, I reassembled enclosure with the cockroach Lingyi attached to enhanced heatsink, and a new 1/8" full sized closed cell foam gasket was compressed inbetween.

Was kind of surprised how hot the new deep aluminum fins were getting, to the touch.

Last evening on our evening cruise we left with a sub 50% battery, but I had a few beers in me and was gonna go slow and only a short run.

Felt some alarming lack of torque and speed barely a mile in.

At two miles I jammed throttle and it responded but then stuttered and refused.

1/4 mile later lost all power, and one light on remote was flashing red.

Coasted to stop, cycled power button, and two battery bars, all expected torque and speed available. Ran the battery down to 3.3v per cell over a few more miles, lowest ever, trying to repeat weirdness, but never did.

Just came back from another run this evening. Same issues, but noticed weak but unpleasant sounds emanating from usually silent motors at higher throttle when performance sagged.

It shut itself off and restarted while I was still coasting, and all power was back and motor noise gone.

F, I just want to ride, not troubleshoot and stress.
I have no faith in my ability to get my vesc powering my hub motors, which is why I put the reviled Lingyi cockroach back in.
Wish my workbench was not 95f/35c

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The cockroach lingyi ESC had a trouble-free 15+ miles accumulated yesterday, and 6 miles earlier today, but on a run just now, felt an abrupt power loss at full throttle when approaching top speed, with half a battery left.

Got off throttle and reapplied, and only 50% power available.

I slowed to some shade, then hit the brakes, only 50% brakes. I stopped, lifted rear truck, and hit throttle, both wheels spun equally.

Neither heatsink, or hub motors felt ridiculously hot. Ordered Fiona back in her chariot, and full expected torque and speed was back, and stayed for the mile return home.

I wonder if hitting the low voltage soft limiter just freaks the ESC out. I noticed similar with the ‘Puaida’ esc, which is also a Lingyi, just not the ebay cockroach lingyi of 5 years ago. Had to come to complete stop before full juice returned.

Also wonder if I have a broken weld that intermittently only shows sometimes.

I’ll recheck p groups via balance leadat 36v next time I open enclosure

Was watching the weather Radar closely, and decided screw it.

Were going.

Towed the FionaYak to the Kayak launch, despite likelihood of Thundershowers.

Paddled hard Northbound, 8.5 out of 10, non stop, to the exposed sandbar in the pass, 2.25 miles/3.62 KM away.

I didn’t notice when Fiona let her ball roll overboard en route, but a woman on a beached boat saw Fiona staring at me, willing me to throw a non existent ball, and from her boat, threw a tennis ball to her, so she got to Frolick and amuse all onlookers until exhaustion.

The southern Horizon had turned black
as the storm’s upper level cirrus outflow spread directly overhead, and blocked the sun.

Everybody pulled anchor, and motored off. Fiona and I started back, southbound, toward the growing storm.

I checked the radar from under a low bridge, and the expanse of red and purple had grown, as the rumbling flashing horizon got even darker, but i thought we could perhaps make it back before it hit, and I laid hard into the paddle.

There is a small uninhabited island in the bay, about midway, where some in the past have set up firepits and left garbage and torn tarps, and such, and as soon as we got close to this, the cold wind hit us in the face, 25 mph steady, 35 mph gusts.

I sliced my foot on some oyster shells pulling the kayak out, and checked the radar again which said it was as bad as it looked.
i then accessed the strewn garbage for making some shelter.

Some pretty good wind chop was rolling in.

There was a pretty big straw like woven floor mat left behind, that I draped over a fallen tree, which served as a roof and a floor, and we waited it out.

Most lightning was well to our East, but one super bright flash was quickly followed by an amazingly loud ‘Crack!’ that Freaked Fiona out badly.

She was shaking hard, sitting on my foot, leaning hard against me while it was raining at an 35.1mm an hour rate Deep red/purplish on the radar.

After about 15 minutes, it let off, and the radar showed the bulk was now north of us.

I stepped from the shelter, and saw there was a 20mph North wind in the bay to assist us the last leg home.

So we left the Island and joined the windchop and tide marching Southward, with bright flashes and loud rumbling at our backs, and all sorts of fish action going on.

Fiona was still shaking with fear, until a cormorant popped up next to us, and stayed alongside, diving and chasing the fish disturbed by our bow wake.

Then it was barkathon and screw the memory of the scary storm.

Made it to the launch and the rain was pretty light, but radar showed more coming. I put the 8" pneumatics back on the kayak cart, and returned hanger to front truck,and slid board into plastic bag for the 1/4 mile walk to asphalt.

Roads super wet and in a cloud of mosquitos, I pulled remote from waterproof smartphone pouch, and esk8 from plastic bag, lifted Fiona into kayak rear well, smeared bloody mosquitoes along my calves, jumped aboard and set off, trying to avoid puddles, as the rain picked up again.

There was one brief powerloss about half way back that freaked me out, but it kept going and got us home.

I pulled loopkey, towelled off the board and aimed fans at it, showered myself and Fiona, and ate a pound of cold pasta.

My shoulders are on Fire.
Feels great, almost.