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Following in The Steps of Carvon

Warning: This is going to be a long story!

My first foray into esk8 was unfortunately with the Skullboard Drive Train, it worked OKish for the first couple of hundred kilometers, nothing impressive, but enough to let me know I wanted to pursue esk8 further but with much better equipment.


stock Skullboard drivetrain courtesy https://www.skullboardvip.com/

I rode these torture devices in total for about 500km until the tires had squared-off to Fred Flintsone specifications, the motors were crap, and suffered awful heating problems, the bearings were crap, but the worst was the vibrations from the squared-off wheels…

When I got better spec crap I pitched these evil beasts into the darkest nether regions of my garage and forgot about them.

Sometime later I came across the great ghost of Jerry Carvon, and started some casual reading up on his direct/hub drives, it appears that he originally used Ownboard hub motors for his first efforts, and they looked similar if not exactly the same as the Skullboard crap.

for science, I drug out my Skull-drives and went to work…

I ripped off the trash tires, cut off the hanger on each side, exposing the 8mm axle (YIKES) when It all bolted together, I put them on a long-abandoned swiss cheese skateboard deck and took it for a ride…

I’ve also come across treads where people attempted to balance these torture devices, and even rewound the little bastards for better performance.

Obviously these will never be high-performance drives, but I thought maybe if I could take out the vibrations maybe these would make a fun tool around the neighborhood eska8 with little additional money invested, and would also give me a platform to learn a little bit mor about motors, rewinding, etc…

Stay tuned, I’ve just started this crazy experiment…

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watching this thread

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Con you clarify how you attached the hub motors to the wheels?

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This title is asking for it.

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ultimately I want to upgrade the axle to 10mm-12mm dia thru the hanger, and add a lock nut to hold the motor onto the axles and the keyed hanger, with a bolt on wheel adapter, but for my initial testing I just exposed the 8mm thru-axle on the hanger, put the motor on, then the wheels and tightened everything up, butt assed tight, against the hanger base and urethane wheel.

I didn’t even key the hanger… the original hubs had 105mm wheels and 58kv, I wished to test these motors out, and determined usability, before I invested any real time or money

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GHOST THREAD

:laughing::stuck_out_tongue_winking_eye::sweat_smile::rofl::joy::8ball:

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I decided to venture off in a slightly different means to the same conclusion and picked up some cheap Carvon direct-drives from @Saturn_Corp…

They needed some work…

yes there were stripped screws, yes the motor(s) needed new bearings, the phase wires were all f*d up, I ran an inductance test on them before dissassembly… but I got them apart, sad to note that all motors could used new bearings, but I received one set, I had spare stock of the 6900 bearings but had to purchase more 6805 bearings and some 12ga silicone phase wires… I’m hoping the locked motor is only from the myriad of ferric-metal found the in motor can, guessing most were ferric sand and bearings as there in no evidence of metal to metal contact in the can.

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test 3 on phase wire replacement…

test 1: just heat up the motor winding wire and apply solder… fail too much enamel residue remaining in the join.
test 2: sand/scrape enamel from motor wire… too much time involved, Carvon wound the motor with 12 wire groups, 12 wires per phase x 3 phases x 2 motors = 72 motor wires to clean…
test 3: Success, I spoke with our resident motor expert @hummieee and he recommended heat first then clean of enamel residue…

Heat then slow-moving wire brush dremel, then heat and isopropyl alcohol, then twist, flux, then solder…

success

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Got a pic of this?

Like soldering iron, or heatgun, or … ?

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First I stripped the heat shrink/wire covering and carefully flayed out and splayed the wire so I could get at each individual strand of motor wire…

Then used a cigar lighter type butane torch, you can visually see the enamel burning off and the copper change color… this only took a brief second or two…

Then used fine wire brush from a standard dremel tool, I laid each strand on my thumb-nail and following rotation of the tool fired up the dremel on it’s lowest speed and with only very light pressure spun the wire brush towards the blunt end of the wire so the spin of the wire brush tended to straighten and lengthen the wire strand.

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Be careful I think he lost a leg to these things

AFAIK he modded SK3 motors, no rewind? But not absolutely sure for the v4…

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Likely… I don’t know the complete history of Carvon, he came and ghosted us before I got into esk8, and I have no idea what an SK3 looks like internally, but there is an awful lot of shims and adapter-like bushings in this motor… The motor does look machine-wound vs. Hand wound however… Id like to get a peek at the internals of an SK3… It may yield spare parts or a method to produce more… Any idea what the Kv of an SK3 is?

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image

All the motors we use, unless there’s a disconnect from the driven wheel by a freewheel or something so it will coast, are potentially leg removing if not worse when the motor shorts from abuse or even enough hours of even regular use. When a motor shorts within a single coil the motor will be destroyed but you’ll count yourself lucky because if it shorts across coils or phases it’s equivalent to slamming on your brakes. This is possibly deadly. Luckily you can wind any motor doing every other tooth instead of every tooth as usual and it won’t be able to possibly short across coils and it’s even A BETTER MOTOR electrically. It has a better magnetic circuit (winding factor) and in my experience and others you can get more wire on, both amounting to better efficiency and less heat.

I don’t know the details on how motor manufacturers for vehicles take care to make sure a cross phase shorting doesn’t happen or what other safety measures are there to make sure the brakes aren’t surprisingly slammed on but in our case that’s how it will go. I’ve had even what I believe was a short within a single winding and was launched from high speed. The motor still ran but badly and I rode home slowly.
All motor magnet wire is rated to sustain a certain temp for 20,000 hours, that’s the standard. I don’t know what the wire rating is with the common rc motors we use but the cost of wire increases a lot as you go past 200c wire. (I’ll be using 240c rated stuff going forward).
Jason of grin tech and owner of endless sphere has testing on ES registering the temp, with temp sensors, of different places within a motor and it will be potentially much higher than what is on the case or even the edge of the windings.
We drive motors very hard pushing them to temps higher than likely any other use. I’m freaked by the risks but it’s possible to wind LRK, fix everything inside solidly and add further insulation on any wires of separate phases that cross. You can virtually guarantee no cross-phase shorting by doing this.

And now I ask you my fellow Americans… or no I mean skaters… retire those super roasted outrunners, wind again, and we will ride up stronger than before! (Watching the impeachment)
(found my old motor in google search which had too much winding to fit) …and just heard from the mouth of MWS wire u can extremely shape magnet wire after the enamel is already on and the manufactures shape a lot of the wire after it’s on: you can press the sides of the stator flattening the end turns to make it fit if needed.

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For science Carvon V4 (???) Measurement:


External Can: 61mm dia. X 61mm long.



Internal can: 56mm 14 curved magnets.


Stator: 50mm dia x 36mm long 12 teeth

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Kinda bummed… But it is what it is… I got the new motor bearings today and started work on the other motor…

The motor end can bearing seat is oblong and out of round by .1mm, my guess is that riding this with fucked bearings caused the bearing seat to oblong…

Considering options but I think at first I’ll just put the motor back together and see just how badly the motor rocks on that side…

Definitely not stoked!

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just ordered this board for this little grocery getter…

31" long, 8.5" wide hopefully it’s somewhat stiff, if not some glass on the bottom, and maybe the top… it ain’t going to be what you expect… it’s going to be somewhat kooky and have a 12s2p battery!

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Maybe big gap filling retaining fluid would make the bearing solid.

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That sucks big balls, hope you can find a solution to that, or if you can’t; hope it’s a minimal issue.

BTW that deck, you say it’s not what I expect, but I am expecting a schlongboard now!

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hmmmmmmmmmmmm ok!

Don’t for one moment think that you can’t put 110mm wheels and RKP trucks on a short deck, because you can :smiling_imp:

you most definitely can

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