Old Man Cruiser New Re-Build

ESK8 Electronics
#1

Hi all. I’ve posted a few times as I was trying to work my way through a ‘cheap’ build but the more I read, it has become apparent the less I knew.

I had been building a 46" pintail cruiser. I had purchased almost all of my parts second hand (though new) but blew it thinking I could use some old 18650 batteries. Most were Samsung or LG but they suck. I tried using soldered battery sleds but during my first ‘real’ ride I had multiple failures. Kinda discouraging.

My goals are still 10-12 miles on a single charge with a weighted speed up to 25 mph. Can you all review this list and tell me if it looks ok? I’m struggling with the batteries most. Thanks…

What I have: Turnigy Aerodrive SK3 - 6354-260kv http://www.hobbyking.com/hobbyking/store/__18127__Turnigy_Aerodrive_SK3_6354_260kv_Brushless_Outrunner_Motor.html Enertion VESC Ver 4.12 fw 2.18 http://www.enertionboards.com/electric-skateboard-parts/vesc-standard/ Sparkless On/Off Switch 2s-12s 120A/60V diy-electric-skateboard-kits-parts/electric-skateboard-on-off-power-switch/ TorqueBoards 2.4Ghz Mini Remote Controller diy-electric-skateboard-kits-parts/torqueboards-2-4ghz-mini-remote-controller/ 46" Pintail Cruiser Deck http://www.ehlerslongboards.com/index.php/complete-longboards-skateboards/customize-your-own-pintail-9-5-x-40-complete.html Enertion Trucks http://www.enertionboards.com/electric-skateboard-parts/longboard-trucks.html 83mm Wheels Pulleys- 14t/35t

What I don’t have: ZIPPY Flightmax 8000mAh 4S1P 30C x2 http://www.hobbyking.com/hobbyking/store/_20823__ZIPPY_Flightmax_8000mAh_4S1P_30C_US_Warehouse.html Turnigy P606 LiPoly/LiFe AC/DC Charger (US Plug) http://www.hobbyking.com/hobbyking/store/_97456__Turnigy_P606_LiPoly_LiFe_AC_DC_Charger_US_Plug_US_Warehouse.html

Will these batteries do what I want (in series)? Or should I go with something else? How about this charger? Is it ok? I am ready to pull the trigger…:grin:

1 Like
#2

Everything seems fine. You should hit almost 30mph (I’m assuming you meant 14/36 ratio, not 14/35) if not more. I’d consider dropping to 6s if you don’t want to go that fast.

I’d recommend getting a nice 18650 or 26650 pack instead, but lipos work as a cheaper alternative. You should get about 14 miles on flats on your battery.

#3

Charger can only do 6s max reading from the specs. This would work if you put the 4s in parallel to charge. If you want to keep them in series while charging (==8s) you need to find a different charger.

Dropping to 6s (2x3s, 1x6s) like @jinra suggest would obviously work as well :slight_smile:

#4

Hmm, if I put in your info in the calculator with 6s I get a top speed of only 22mph (unweighted):

http://calc.esk8.it/#{“batt-type-lipo”:1,“batt-cells”:6,“motor-kv”:260,“system-efficiency”:80,“motor-pulley-teeth”:14,“wheel-pulley-teeth”:35,“wheel-size”:83}|

since you mentioned you want to go at least 25 mph weighted this would not suffice. 8s would get you in the proximity of 25. Whilst 10s would definitely get you there. Problem with 10s is that you would have an eRPM of +/- 67000+ which as I remember is too much for the vesc to still be reliable :frowning:

#5

perhaps 8s with 90mm wheels? (32 mph unweighted, 25mph weighted with a guestimate of 80% efficiency)

#6

Hey thanks for the quick response!

There are a few reasons for my going with the lipos…Mostly though, I don’t trust my own handywork. I’m sure I’ll have some bad soldering nail me about 5 miles into a ride! :stuck_out_tongue_winking_eye: And then I’ll incur further costs to fix or have someone else do it.

#7

Wow this is oddly similar to my build, I used the 44" bamboo pintail on 97mm clones.

tried the 83mm’s for a while but 97mm are so much smoother if you don’t mind the weight… just keep riding and yo won’t notice tho…

1 Like
#8

Ok, this is what I needed to know! I was thinking I could just unhook the series and charge them separately, but that would be a pain. Any suggestions on a charger?

I like the 8s setup. What happens if I drop to constant discharge of 10C per pack like in this one? Multistar High Capacity 4S 10000mAh Multi-Rotor Lipo Pack http://www.hobbyking.com/hobbyking/store/_64438__Multistar_High_Capacity_4S_10000mAh_Multi_Rotor_Lipo_Pack_US_Warehouse.html I know I’ll go about 25% further but what about speed? How much would it be affected?

#9

You should be fine with 100amp discharge. Speed is based on voltage, which should be the same if you run 8s.

1 Like
#10

Wow! I had a hard time even finding an 8S lipo charger. When I did, they are like 4 times the cost. Perhaps I should just put up with disconnecting the series to charge? What do others do?

#11

A lot of people just put up with the disconnecting hassle for charging I believe. Other choices could be a more expensive charger of buying a BMS that you attach to the board/batteries to pair up with a simpler charger. BMS’s however do not seem to be that cheap either. :frowning:

Perhaps you should start with the hassle of disconnecting first. Maybe it’s not that big of a hassle and you’ll be fine with it, and at least you get to ride! After that you can always opt for going a step further…

#12

Ok. I’m purchasing the Zippy’s and the 6s charger. I’ll open the case and charge the batteries separately. Woohoo!

1 Like
#13

+1 on the BMS option, super simple after you get it setup.

1 Like
#14

Yeah! Order confirmed and sent to warehouse for fulfillment! Looking forward to riding…:grin:

#15

Whoop whoop! :heart_eyes:

#16

I usually run 8s (a good moderate setup w/o as much likelihood of DRV issues) - plenty of power for me even on a single motor setup (geared correctly). I also disconnect to charge - not a big deal and i find it plenty easy.

As for chargers - inexpensive ones i recommend is the iMax B6ACv2. If you can swing a nicer one - go for it. I especially like the advanced features of the iMax - similar to nicer ones like iCharger (great!) - like Internal Resistance testing.

I’d avoid any charger that charges via the balance plugs. They are usually much slower and moving 5-6 amps across those small wires seems like a bad idea… but others may do this and have no issues.

#17

How did you attach/protect your gear? I didn’t find anything that would work with the deck’s curvature. I also wanted flex. I ended up using spray insulation sculpted down with silicone covering it. It’s ugly but it works.

#18

a flexy deck is definitely a challenge. The best solution i’ve seen is top mount power so the middle is clean (okp, whitepony, and squad’s are all amazing). Separate your batteries and ESC front and back so the middle can flex. Less area for batteries - but let’s everything work w/o flexing the enclosure and killing a flexy deck.

enclosures - they’ve done custom CF, and abs(Vacuum formed) to fit the vanguard.

i’d read through @whitepony’s build here:

Tons of great pictures and ideas how to do it. GL!

#19

I can’t believe that my Zippy’s and charger have already arrived!!! Now I need VESC experts review my settings. I would rather be a little conservative then burn something up. I can’t pull screenshots (At work and didn’t expect overnight delivery) but have written down what is currently configure. The hardware is the same as listed at the top of this thread. Is this good?

Motor Configuration Motor Tab Current Limits Motor max: 70.00 A Motor min: -30.00 A Batt max: (not sure. 100 A? My 30c at 8000mAh says 240 A but Vedder says absolute max no higher than 150 A. So…?) Batt min (regen): -15.00 A Absolute max: 150.00 A ?? Slow absolute max: CHECKED

Temperature Limits MOSFET Start: 80.00 C Mosfet End: 100.00 C Motor Start: 80.00 C Motor End: 100.00 C

Other Limits Minimum duty cycle: 0.005 Maximum duty cycle: 0.950

RMP Limits (BLDC Only) Limit ERPM with negative torque: CHECKED Min ERPM: -100000.00 Max ERPM: 100000.00 Max ERPMN at full brake: 300.00 Max ERPM at full brake in current control mode: 1500.00

Voltage Limits Minimum input voltage: 8.00 V Maximum input voltage: 57.00 V Battery cutoff start: 26.00 V Battery cutoff end: 24.00 V

BLDC Tab Sensorless: SELECTED Sensorless Min ERPM: 600.00 BR ERPM: 80000.00 Phase advance at BR ERPM: 1.00 Max brake current at dir change: 10.00

Sensorless - Communication Mode Comm Mode: Integrate Integrator Limit: 72.00 Int Limit Min ERPM: 1100.00 BEMF Coupling: 920.00

Hall Sensors (failed during ALL attempted detections) Table: -1/1/3/2/5/6/4/-1 Sensorless ERPM (hybrid mode): 2000.00

Detect Parameters Current: 6.00 A Min ERPM: 600.0 Low duty: 0.05

App Configuration PPM Tab Control Mode Current no reverse with brake: SELECTED

Settings PID max ERPM: 15000.00 Deadband: 0.15 Minimum Pulsewidth (ms): 1.15 Maximum Pulsewidth (ms): 2.05 Use Median Filter: CHECKED Safe Start: CHECKED No other settings configured except Display for monitoring remote control

#20

Battery cut off is a bit low for lipos. may want to take it to 3.5 or 3.6 per cell start with a 3.4 per cell end, though it really depends on your pack.

Have you done motor detection? Integrator limit seems a bit low.

Batt max just match to your motor max.