[First] Green thing | Earthwing 41" Supermodel | 97 Flywheels 75a | Need help on electronics

After lurking for too long, finally started building my own build.

For starters I built regular longboard to learn how to ride. Current build is:

Earthwing 41" Supermodel Green Stain deck Caliber I 50 degree trucks (green as well, not seen in picture) Abec 11 97mm 75a flywheels First Abec7 Green bearings I could find

Planned parts:

Battery: Initially was thinking about lipo, but recently changed my mind and will probably go with 18650 using battery holders like this:

For batteries themselves: https://eu.nkon.nl/samsung-18650-inr18650-25r.html And I will try making each pack <99Wh, just to have an option of air travel. As much as I calculated, itā€™s 9.25Wh per battery, so 10 batteries per pack connected together? Not sure tho about what pack to go in general tho (10s3p, etc.). The goal is commuter board, dont really care about high speed nor huge hill climb.

Motor: While I would like to have dual (for braking mostly, especially to have some brakes in case one motor fails), I donā€™t have that kind of budget yet. So for now Iā€™m thinking about 6374 192kV 3300W. Or should I go with smaller one and later add a second one? Iā€™m 90kg person just to mention.

VESC: esk8.de one, because of it being europe based, so no additional VAT tax.

Controller Again something Iā€™m not sure about, want something as small as possible and reliable. Nano?

Questions summed up

  • What am I missing and especially what small things I could order now from chinese on ebay/aliexpress, since Iā€™m starting my actual build at the end of the month, when I get my salary. So that they could actually arrive on time (god bless 1 month delivery time)
  • What battery specifications I should go with if I donā€™t really care about big speed/torque/hill climb, am 90 kg person
  • Is 6374 too much? Can I go with some smaller motor to which later I could add second identical one to make it dual?

Thanks!

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Donā€™t get 25r - voltage sag is a pain with them. Get 30Q! battery holders like these are also not well suited for the currents we use.

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The 6364 should have enough power and itā€™s possible to use a second one with torque boards extra wide trucks.

diy-electric-skateboard-kits-parts/torqueboards-218mm-trucks/

Is it because of the wires? Because Iā€™m fine with resoldering them with stronger ones, or soldering those packs directly (If for example making single pack slim tower looking pack). I just donā€™t want to solder batteries because my soldering iron isnā€™t really powerful and I donā€™t have proper soldering skills imo to solder battery pack without damaging it.

Iā€™m fine with changing the batteries tho. Thanks!

They are 218mm, I have 10 inch Calibers, so 254mm, which means I should be ok?

the springs are used to carry the current and are too thin. also vibrations will cause cells to slide out of their holders eventually if not secured properly.

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the 218 are NOT from end of axle to end of axle but the hanger width AFAIK.

Oh right, in torqueā€™s description they write that ā€œThe truck profile is similar to Caliber but slightly bigger by 1mm.ā€. As much as i understand profile == width, so i still pretty much should be ok?

On other note: Are there any other cheap battery holders that would be good enough for the this current, or should I just get proper soldering iron?

Get a spotwelder

Expensive one use item. Iā€™d rather get a good powerful soldering iron

Someone said nkon.nl will weld up battery packs. I think having a battery professionally welded is money well spent.

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This is something new, canā€™t really find this info on their site, will try writing their support. Thanks

If youre going for a dual drive, now or later, 2x 6355 is a LOT of power at 10S. I have 2x 6355 at 10S and I literally cant go full throttle because the board just shoots away from under my feet.

If you start with one 6355 then youā€™ll probably be fine on small slopes but maybe not on steep hills.

I use VESCX (now ā€˜FOCBOXā€™) which I highly recommend, having the ability to do FOC without to much risk is great, The housing also makes it a bit more foolproof against accidental shorts.

Also, going sensored is definitely worthwhile imo.

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While I would like enertion focbox, itā€™s a bit out of my price range (200$ + 25% Vat tax + 20$ item check cost). I will probably go with Esk8.de VESC 4.12(150 eur) since itā€™s Europe based. It supports foc as well, but they say itā€™s experimental and still in development so ā€˜use at your own riskā€™ .

why do you want to use foc? BLDC is great

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I donā€™t, I just like having options. I mean FOC is as much as I understand is more efficient, but not as reliable yet? Anyways as mentioned Iā€™m planning on esk8.de vesc, unless I find cheaper reliable option that is europe based.

If you do not want to spot weld the batteries check this recent postā€¦

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For anyone else interested about nkon.nl pre-welding pack - I asked them about it and how much additionally would it cost to the battery price for pre-welding it (30 batteries), their response:

''Hi,

About 40 euro for the welding I estimate, depends on exact requirements.

Regards, Arjanā€™ā€™

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i did the same thing today and had the same quote, i think i will probably end up doing this when i order my cells

Finally got mechanical kit from ebay, seemed fine, except for in motor mount the hole to put on the truck is round, while my truck is square. So I ended up doing terrible thing -> made my truck rounder. Looks horrible, but didnt want to order another mount, not sure even if I could find one that would fit. Anyways my truck costs almost as much as motor mount so in worst case I will just get a new truck.

Itā€™s a salary day as well, so I will finally start ordering main components. And once again I started to wonder again whether I should go with lipo or lion. ~140 EUR for a battery seems kind of a lot (lion 10s3p 30Q) while I could simply get 2 lipos like this https://hobbyking.com/en_us/zippy-flightmax-5000mah-5s1p-20c.html and get 10s. Of course thereā€™s the bursting in fire thing and less recharges.

Iā€™m still thinking about solderless battery pack with 18650, I just received battery holders that I forgot I ordered, which look like these:

While they donā€™t have springs, they say its for 3.2-7.4V, so 2S only? But what could go wrong, the contacts seem big enough, at least bigger than springs on the previously mentioned ones.

  • Are SK3 motors from HobbyKing sensored? Should I just get it there or get ~50% more expensive one in esk8 related eshop (esk8.de/aliensystems)?

Edit: I totally forgot about rangeā€¦ ~10s1p lipo would have only about ~6 miles? While 10s3p lion would have ~16. So probably will end up with 18650s.

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