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A guide to building a fast electric skateboard at home

eskateboard.huu.la

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Re: A guide to building a fast electric skateboard at home

#61

Post by edaemon »

franciscop wrote: post #40

We need links to the different parts please: "Motors are relatively easy, just use a wrench to put the wheel in place". This is only true if you find the right type of motor, which is not easy at all IMHO.

While I'm not the OP, I can provide the links to the parts I used for my electric skateboard. The ESC I used is one of those mentioned in the post.

Batteries (x2): https://hobbyking.com/en_us/zippy-flightmax-8000mah-5s1p-30c...

ESC: https://www.ebay.com/itm/Dual-motors-longboard-skateboard-co...

Motors: https://www.ebay.com/itm/90mm-dual-6364-hub-motors-drive-kit...

BMS (optional): http://www.batterysupports.com/36v-37v-42v-10s-60a-10x-36v-l...

Deck: https://www.skateshred.com/index.php/wholesale-blank-longboa...

This is how I wired them together: https://i.imgur.com/tEI4H0E.jpg

It's been working really well for me so far.

Re: A guide to building a fast electric skateboard at home

#62

Post by stinos »

walrus01 wrote: post #45

> "I have tried Li-ion batteries like Panasonic NCR18650B, LG He4, none are not as good as a cheape Li-po batteries you can get from Ebay. " that's scary as hell considering the battery is likely to take physical abuse. Look at the number of fire incidents caused by drone LiPo charging. There's a reason why serious drone enthusiasts charge their batteries in special battery bags.

It's not just LiPos: while the 18650 are (afaik) safer to charge, they have the problem that the entire outer part except the top is the negative pole. Meaning the slightest damage to the wrap can cause it to get exposed: if you put to batteries in series, next to each other, and their negative poles touch, max current flows and produces enough heat to set things on fire and possibly causes explosion. Happens every once in a while in the vaping community for instance.

Re: A guide to building a fast electric skateboard at home

#63

Post by stinos »

loeg wrote: post #39
antisthenes wrote: post #6

If I'm going 50km/h on something, I would at least like it to have proper disk brakes like mid-range and higher bicycles do. Going at those speeds may be fun and all, but you're 1 careless driver away from the hospital, unless you ride on abandoned roads.

Yeah, lack of brakes on a 50 km/h vehicle is a problem. And in the case of skateboards, lack of handlebars too. That said, disks aren't essential for good bicycle stopping performance. Good rim brakes (like most mid or high end road bicycles) stop just as quickly as disk brakes in dry conditions . Rim brakes are not really an option for long boards, though.

lack of brakes

Sliding/skidding (where the board is manoeuvred in the direction perpendicular to the movement) will make you loose speed pretty quickly.

Apart from that motor can be used to brake. Not sure what exactly is needed for it, but a DIY board I rode once had a dual trigger on the remote, one direction for moving forward, the other one for braking. Pretty convenient though won't stop you as quick as some friction brake.

lack of handlebars too.

That is only a problem if you either don't know how to steer with the board, or are trying to take sharp turns at too high speed. Both conditions which are equally true for other vehicles, main difference being some vehicles will be able to turn sharper than others given the same speed. And some are easier to control than others. But enough skill can deal with that.

Re: A guide to building a fast electric skateboard at home

#64

Post by paulmd »

bhhaskin wrote: post #56
walrus01 wrote: post #45

> "I have tried Li-ion batteries like Panasonic NCR18650B, LG He4, none are not as good as a cheape Li-po batteries you can get from Ebay. " that's scary as hell considering the battery is likely to take physical abuse. Look at the number of fire incidents caused by drone LiPo charging. There's a reason why serious drone enthusiasts charge their batteries in special battery bags.

I think part of the problem is that people just don't know any better. A battery is just a battery, like any other battery. They don't know that there are different chemistries and physical properties at work.

I did electric airplanes about 15 years ago, and there were distinct differences in the quality of various brands and models. Airplane usage is very intense, during takeoffs and climbs the propeller is under very intense resistance (effectively stalled) and power consumption is very high. The exact amount depends on your motor windings and your propeller size/pitch, and generally the more current the powertrain will push the better the aircraft would handle.

Started with Sub-C car packs, those sucked pretty badly. Then switched to HeCell 2/3A (~2000 mAH?) NiMH cells, those had good capacity but weren't the best discharge rates, they wouldn't do more than 20A peak or so. KAN 2/3AAs had pretty good discharge rates (could do 30-40A peak) but the capacity sucked (1100 mAH). All of these types of batteries tended to die after a season or two of flying, sometimes less than a season, they just couldn't handle that discharge.

Finally settled on Sanyo 4/5A FAUP 1950mAh cells, they were expensive as hell (2-3x as much as a cheap pack) but could handle insane amounts of discharge and had good capacity. They were rated to at least 45A continuous discharge and in practice could be pushed up to 75A peak loads without issue. For you whippersnappers, that would be roughly a 40C peak discharge, which LiPos couldn't touch at that time. They were also the only battery that ever lasted more than a season without issue, could easily get two and maybe a third with reduced life.

It looks like they're discontinued, which isn't surprising since everything has moved from NiMH to LiPo, but if you were doing really intense discharges like this, they would probably be my cell of choice. I've never seen a cell before or since that could handle that much discharge. LiPos are not always the answer.

LiIon is certainly not the answer for a fast-discharge application like this. They are not really any safer than LiPo, the casing is physically stronger but they will explode/burn when ruptured just like a LiPo, and they do not like high-discharge scenarios. Think laptops, not electric motors. Running a motor this big on a LiIon will end poorly, if you're lucky it will only be a fire.

Re: A guide to building a fast electric skateboard at home

#65

Post by agumonkey »

kevining wrote: post #31
agumonkey wrote: post #27

50km/h is suicide. ps: anybody here owns a gyrowheel ?

Electric unicycle? I own several. Some will even go over 50 km/h, though I don't dare go that fast. It's just safe to have the extra power when needed.

I asked about electric uni not for speed btw. I've seen a few and people were faster than traffic even at moderate speed (in city of course), looked relaxed as fk, the device was small. I don't know about energy efficiency but I was tempted to drop all other mode of transportation after seeing that.

Re: A guide to building a fast electric skateboard at home

#66

Post by agumonkey »

throwaway76543 wrote: post #41
agumonkey wrote: post #27

50km/h is suicide. ps: anybody here owns a gyrowheel ?

I go 40 km/h regularly on one of these things, it feels slower than it sounds. I've also fallen at that speed, wearing no protective gear other than a helmet. Not the end of the world, no different than when I fell off a roadbike going roughly the same speed. If you're worried about scrapes throw on a motorcycle jacket. But if you know how to fall, 40-50km/h is manageable without gear -- aside from the mandatory helm…

I may have took the title differently. I thought it was a casual thing for people to move. If you have the skater mindset, it will probably be ok, but I still think it's suicide to float at 50km/h unprotected.

Re: A guide to building a fast electric skateboard at home

#67

Post by agumonkey »

adrianN wrote: post #55
jdavis703 wrote: post #28

Earlier quoted context omitted.

No it isn't. The world record is 146.73 km/h (91.17 mph) by Peter Connolly [0]. While most skateboarders never go that fast, downhill racers routeinly hit very high speeds [1]. [0]: http://www.guinnessworldrecords.com/news/2018/2/watch-this-s... [1]: https://en.wikipedia.org/wiki/Longboarding#Downhill

And racecar drivers go really fast as well, but that doesn't mean that normal people can safely drive that fast.

Elon musk car went to thousands of mph and its driver is still in one piece. QED /s

Re: A guide to building a fast electric skateboard at home

#68

Post by z3t4 »

truculation wrote: post #19
keyle wrote: post #5

Very cool but the original board was never designed to go at such speeds. I suspect you'll ruin the wheels fairly quickly, not to mention you might lose control at high speed fairly fast. I'm not a skateboarder myself, but I've moded some bikes and adding speed is the easiest part, making it useful speed is way harder. Also, I hope the engine can go in reverse or this guy has no breaking power; and as he gets comfort…

Yep, high speed can definitely ruin a wheel(!): https://twitter.com/machinepix/status/969654857895301120

not fair as those water jets can cut through just about everything.

Re: A guide to building a fast electric skateboard at home

#69

Post by voxadam »

edaemon wrote: post #61
franciscop wrote: post #40

We need links to the different parts please: "Motors are relatively easy, just use a wrench to put the wheel in place". This is only true if you find the right type of motor, which is not easy at all IMHO.

While I'm not the OP, I can provide the links to the parts I used for my electric skateboard. The ESC I used is one of those mentioned in the post. Batteries (x2): https://hobbyking.com/en_us/zippy-flightmax-8000mah-5s1p-30c... ESC: https://www.ebay.com/itm/Dual-motors-longboard-skateboard-co... Motors: https://www.ebay.com/itm/90mm-dual-6364-hub-motors-drive-kit... BMS (optional): http://www.batterysupports.com/36v-…

What wheels and trucks are you using?

Re: A guide to building a fast electric skateboard at home

#70

Post by jimnotgym »

loeg wrote: post #36
jimnotgym wrote: post #26

Is a similar thing possible with a micro-scooter? My son would love this as a project if anyone has any resources.

It's just motors and wheels. No reason it wouldn't be possible with any other wheeled device. Electronic motors + drivetrain are nice and simple compared to petrol engines.

I was having trouble finding the same kind of hub moters sized for scooter wheels... The rest looks trivially similar
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