Kryptonics Board hub motor

Lightweight / Folding / Portable EVs - seats optional
Outgrown   1 mW

1 mW
Posts: 18
Joined: Apr 06 2015 8:06pm

Kryptonics Board hub motor

Post by Outgrown » Apr 07 2015 7:17pm

Recently, I got a Kryptonics board from wal-mart. With a quick change of bearings and bushings, it holds quite well to my Penny Board, but I am willing to take things to the next level. Considering how cheap the board is, I am willing to kick it up a notch to make it motorized.

I have done some research and went to some hobby stores for some help, but it always looked clunky and unappealing in terms of performance and turning (Pen E board, Kickr). With that in mind, I thought of putting one motor inside the bottom left wheel along with a flat battery pack for the bottom of the deck. (The hobbyist explained that if the battery is to rupture in some way, it will heat rapidly and may risk my life)

I am aware of the fact that more components are needed (ESC, Speed controller, etc), which is why I am here to ask questions from experienced people. I am very new to this field and community and would like to make this project a reality with you guys.

Any help or opinions? Where should I start?

torqueboards   100 MW

100 MW
Posts: 2940
Joined: May 27 2013 10:02pm
Location: San Francisco, CA
Contact:

Re: Kryptonics Board hub motor

Post by torqueboards » Apr 07 2015 9:00pm

Your probably better off getting a better deck if it's a cheap deck. A deck only costs $50 to $100+.

What your looking for is a "friction drive" electric skateboard and not a hub motor.

It's not too often that a pack will rupture or heat up. Only if your truly irresponsible would something like that happen. Like mentioning a miter saw cuts fingers.

You need the basic components - batteries, esc, motor, rc controller.

You can go with 6S, 8S battery. The higher the more power. A 5065 motor should be good but a bigger motor will most likely be durable.

Checkout Pen E Board and purchase similar to his :mrgreen:
DIYElectricSkateboard.com Electric Skateboard Kits

Outgrown   1 mW

1 mW
Posts: 18
Joined: Apr 06 2015 8:06pm

Re: Kryptonics Board hub motor

Post by Outgrown » Apr 07 2015 9:17pm

torqueboards wrote:Your probably better off getting a better deck if it's a cheap deck. A deck only costs $50 to $100+.

What your looking for is a "friction drive" electric skateboard and not a hub motor.

It's not too often that a pack will rupture or heat up. Only if your truly irresponsible would something like that happen. Like mentioning a miter saw cuts fingers.

You need the basic components - batteries, esc, motor, rc controller.

You can go with 6S, 8S battery. The higher the more power. A 5065 motor should be good but a bigger motor will most likely be durable.

Checkout Pen E Board and purchase similar to his :mrgreen:
Would a friction drive motor inside of a wheel still be possible? Or is that only for hub motors?

torqueboards   100 MW

100 MW
Posts: 2940
Joined: May 27 2013 10:02pm
Location: San Francisco, CA
Contact:

Re: Kryptonics Board hub motor

Post by torqueboards » Apr 07 2015 9:25pm

Outgrown wrote:
torqueboards wrote:Your probably better off getting a better deck if it's a cheap deck. A deck only costs $50 to $100+.

What your looking for is a "friction drive" electric skateboard and not a hub motor.

It's not too often that a pack will rupture or heat up. Only if your truly irresponsible would something like that happen. Like mentioning a miter saw cuts fingers.

You need the basic components - batteries, esc, motor, rc controller.

You can go with 6S, 8S battery. The higher the more power. A 5065 motor should be good but a bigger motor will most likely be durable.

Checkout Pen E Board and purchase similar to his :mrgreen:
Would a friction drive motor inside of a wheel still be possible? Or is that only for hub motors?
Only hub motor has a drive motor inside the wheel. Friction drive is what the Pen E Board, Kickr is.
DIYElectricSkateboard.com Electric Skateboard Kits

Outgrown   1 mW

1 mW
Posts: 18
Joined: Apr 06 2015 8:06pm

Re: Kryptonics Board hub motor

Post by Outgrown » Apr 07 2015 9:42pm

torqueboards wrote:
Outgrown wrote:
torqueboards wrote:Your probably better off getting a better deck if it's a cheap deck. A deck only costs $50 to $100+.

What your looking for is a "friction drive" electric skateboard and not a hub motor.

It's not too often that a pack will rupture or heat up. Only if your truly irresponsible would something like that happen. Like mentioning a miter saw cuts fingers.

You need the basic components - batteries, esc, motor, rc controller.

You can go with 6S, 8S battery. The higher the more power. A 5065 motor should be good but a bigger motor will most likely be durable.

Checkout Pen E Board and purchase similar to his :mrgreen:
Would a friction drive motor inside of a wheel still be possible? Or is that only for hub motors?
Only hub motor has a drive motor inside the wheel. Friction drive is what the Pen E Board, Kickr is.
Yes I don't want to make it like the Pen E or Kickr, I am trying to retain functionality and aesthetics of the board

torqueboards   100 MW

100 MW
Posts: 2940
Joined: May 27 2013 10:02pm
Location: San Francisco, CA
Contact:

Re: Kryptonics Board hub motor

Post by torqueboards » Apr 07 2015 9:48pm

You'll have to read http://endless-sphere.com/forums/viewto ... 35&t=68392 and a few others on hub motors.

If you plan on doing it yourself. You will need access to a lathe and CNC machine.
DIYElectricSkateboard.com Electric Skateboard Kits

Outgrown   1 mW

1 mW
Posts: 18
Joined: Apr 06 2015 8:06pm

Re: Kryptonics Board hub motor

Post by Outgrown » Apr 08 2015 12:23pm

torqueboards wrote:You'll have to read http://endless-sphere.com/forums/viewto ... 35&t=68392 and a few others on hub motors.

If you plan on doing it yourself. You will need access to a lathe and CNC machine.
I do have access to those. Is there a tutorial for this purpose?

User avatar
beto_pty   1 kW

1 kW
Posts: 480
Joined: Dec 17 2013 8:20am
Location: Panama City, Republic of Panama

Re: Kryptonics Board hub motor

Post by beto_pty » Apr 08 2015 5:05pm

Outgrown wrote: Is there a tutorial for this purpose?
Yup.... you get to write it... :D
Do or Do not. There is no try
PATY/neta http://endless-sphere.com/forums/viewto ... 35&t=65384
MIni-motor Build http://endless-sphere.com/forums/viewto ... 35&t=56839
Destroyer http://endless-sphere.com/forums/viewto ... 35&t=58504
Adrianas Board http://endless-sphere.com/forums/viewto ... 35&t=61171
Gargoyle http://endless-sphere.com/forums/viewto ... 35&t=61569
Velociraptor: 6s 10.4ah, Ezrun150, 9.8 mm abec11s, Quanum, 5060NTM, 16/48 hdt5, Piggyback Charge

Outgrown   1 mW

1 mW
Posts: 18
Joined: Apr 06 2015 8:06pm

Re: Kryptonics Board hub motor

Post by Outgrown » Apr 08 2015 5:25pm

beto_pty wrote:
Outgrown wrote: Is there a tutorial for this purpose?
Yup.... you get to write it... :D
What about this guy? http://endless-sphere.com/forums/viewto ... +hub+motor

He seems to know what he's doing

Hightower   10 W

10 W
Posts: 68
Joined: Mar 14 2015 10:45am

Re: Kryptonics Board hub motor

Post by Hightower » Apr 09 2015 8:22am

It looks like you want to recreate Stielz hub motor. And why wouldn't you? That thing is a beast!!!

A couple key factors on how he was so successful:

- 2 hub motors is MUCH better than one. Hub motors systems suffer from not being able to adjust torque and speed due to no gears/gear ratios. With this in mind, Single motor systems using gearing can make up for this lack and as such, having 2 geared motors isn't as much of a factor to performance as it is with hub motors.

- Choice of motors is important. The inability able to adjust speed and torque output through gearing, your initial choice of a motor is going to effect your overall performance greatly. This is why Stielz went with a large, low kv motor. Small high Kv motors just won't be able to get the job done.

- He modified his motors with hall sensors, effectively making them sensored motors. They will perform much better at low rpm than unsensored but are more expensive/difficult to mod.

- 92mm wheels are quite big. The bigger the wheel, the faster you'll go. He probably needed such large wheels just to be able to fit his hub motors inside. Which, from his thread, others have tried to recreate and have shredded their wheels up.

My biggest fear would be either crushing the hub motors under my huge self, or the glue/epoxy failing and lose a wheel and THEN definitely crush my motor lol

-He's pushing over 4,000 Watts, which is a substantial amount of power. That's the equivalent to almost 5 and a half horsepower.

Outgrown   1 mW

1 mW
Posts: 18
Joined: Apr 06 2015 8:06pm

Re: Kryptonics Board hub motor

Post by Outgrown » Apr 09 2015 9:45am

Hightower wrote:It looks like you want to recreate Stielz hub motor. And why wouldn't you? That thing is a beast!!!

A couple key factors on how he was so successful:

- 2 hub motors is MUCH better than one. Hub motors systems suffer from not being able to adjust torque and speed due to no gears/gear ratios. With this in mind, Single motor systems using gearing can make up for this lack and as such, having 2 geared motors isn't as much of a factor to performance as it is with hub motors.

- Choice of motors is important. The inability able to adjust speed and torque output through gearing, your initial choice of a motor is going to effect your overall performance greatly. This is why Stielz went with a large, low kv motor. Small high Kv motors just won't be able to get the job done.

- He modified his motors with hall sensors, effectively making them sensored motors. They will perform much better at low rpm than unsensored but are more expensive/difficult to mod.

- 92mm wheels are quite big. The bigger the wheel, the faster you'll go. He probably needed such large wheels just to be able to fit his hub motors inside. Which, from his thread, others have tried to recreate and have shredded their wheels up.

My biggest fear would be either crushing the hub motors under my huge self, or the glue/epoxy failing and lose a wheel and THEN definitely crush my motor lol

-He's pushing over 4,000 Watts, which is a substantial amount of power. That's the equivalent to almost 5 and a half horsepower.
What an elaborate mouthful! My wheels are 60mm at most, so I may use a cordless drill and its components (Motor, trigger, battery) I have an arduino and a bluetooth nunchuck lying around for adjusting speeds, but would that be a good alternative?

torqueboards   100 MW

100 MW
Posts: 2940
Joined: May 27 2013 10:02pm
Location: San Francisco, CA
Contact:

Re: Kryptonics Board hub motor

Post by torqueboards » Apr 09 2015 9:49am

I think smaller motors (50mm) with low KV can act like bigger motors (63mm) with low KV. You just won't get that added top range in power versus the two but - in reality to have a battery push that much power for what we've been doing is quite a feat. With that said if you have the option to go bigger, might as well anyways.

I think if everyone is going hub motors it should also be sensored or vesc (at least). Would work a lot better but perhaps it's similar to just the regular belt/pulley setup then you might not need sensored when it's running.

I have jacob's hub motor setup and I'll be testing it out soon. Need to setup a board for it. We'll see how well it works soon.

@Outgrown - You would want to use a wheel way bigger than 60mm as it would be hard to get significant power within that small diameter with enough space for the wheels urethane as well.
DIYElectricSkateboard.com Electric Skateboard Kits

Outgrown   1 mW

1 mW
Posts: 18
Joined: Apr 06 2015 8:06pm

Re: Kryptonics Board hub motor

Post by Outgrown » Apr 09 2015 10:06am

torqueboards wrote:I think smaller motors (50mm) with low KV can act like bigger motors (63mm) with low KV. You just won't get that added top range in power versus the two but - in reality to have a battery push that much power for what we've been doing is quite a feat. With that said if you have the option to go bigger, might as well anyways.

I think if everyone is going hub motors it should also be sensored or vesc (at least). Would work a lot better but perhaps it's similar to just the regular belt/pulley setup then you might not need sensored when it's running.

I have jacob's hub motor setup and I'll be testing it out soon. Need to setup a board for it. We'll see how well it works soon.

@Outgrown - You would want to use a wheel way bigger than 60mm as it would be hard to get significant power within that small diameter with enough space for the wheels urethane as well.
What if it's more for assist purposes rather than it being entirely its own vehicle? I just want a boost when I pedal uphill or a small boost for downhill as well, but there isn't any long term motor running.

Hightower   10 W

10 W
Posts: 68
Joined: Mar 14 2015 10:45am

Re: Kryptonics Board hub motor

Post by Hightower » Apr 09 2015 10:10am

My wheels are 60mm at most, so I may use a cordless drill and its components (Motor, trigger, battery) I have an arduino and a bluetooth nunchuck lying around for adjusting speeds
I agree with what torque said about the wheels. It would be hard to get a strong enough motor inside of such small wheels without risking the structural integrity of the wheel itself. If this is a project that you can build with stuff around the house, perfect. If this is something that you are investing some serious money into, then be sure to plan it out accordingly. Frying electronics gets expensive fast!

With that said, I can't wait to see what you might do with that cordless drill! I've been dreaming up a few battle bot-esque devices to make out of some drills I have laying around. One of which includes an RC snow plow, so I can plow my driveway from the warmth of my house :P

@Torque who is this Jacob character. I've heard him referenced many times but I haven't seen his work yet, I don't think...can you link his hub motors?

Hightower   10 W

10 W
Posts: 68
Joined: Mar 14 2015 10:45am

Re: Kryptonics Board hub motor

Post by Hightower » Apr 09 2015 10:18am

Brushless outrunner motors work differently from brushed motors that you'll find in cordless drills. Both have their advantages/disadvantages

Most people building these eboards use the brushless outrunner motors. When powered a shaft and the outer can of the motor rotate together. This feature makes them an absolute necessity for the hub motor design based on the outer rotating can alone.

Motors found in most cordless drills are brushed, and the only rotating part is the shaft. They can be used to power an eboard via gears, but generally are avoided. There might be someway to get brushed motors to work as a "hub motor" but the motor shaft would be under your weight constantly and apt to bend/break.

This might clear the air up a little.

Edit: sorry for the double post....almost just made it a triple.
What if it's more for assist purposes rather than it being entirely its own vehicle? I just want a boost when I pedal uphill or a small boost for downhill as well, but there isn't any long term motor running.
As soon as you attach a motor to your wheel, whether by gears, friction force, or as a hub motor, you will feel additional resistance. If you try turning a motor shaft by hand, you also feel this same resistance. If you aren't using the motor while you ride, it will resist your kick pushing and tire you out faster.

With that said, my batteries have died over a couple miles from home. I had to kick push it back, no big deal. Did it suck? Not really. Do I want to do it again tomorrow? Hell no! I'll be more prepared next ride and time it out better.

User avatar
LEVer   10 kW

10 kW
Posts: 719
Joined: Nov 07 2012 3:29am
Location: SoCal
Contact:

Re: Kryptonics Board hub motor

Post by LEVer » Apr 09 2015 10:46am


Hightower   10 W

10 W
Posts: 68
Joined: Mar 14 2015 10:45am

Re: Kryptonics Board hub motor

Post by Hightower » Apr 09 2015 11:20am

I believe that I use the same $70 motor in my belt driven build as these $200 hub motors and get similar if not better performance. Until the technology gets better, I really don't see any benefit to hub motors. Without any performance benefit over mounted motors, the only benefit to going hub motor is aesthetics IMO. With a mounted setup, after pulleys, belts and the mount, you're getting better performance for a similar price. Adding a VESC to a hub motor would increase it's performance for sure, but it would also increase the performance of a mounted motor as well, so that's a mute point.

If glue is holding the wheels on, it better be heat resistant epoxy or a tight tolerance press fit, because once the wheels get hot from the summer pavement, and your motors heat up from use (there's minimal ventilation inside of a solid wheel)...there may be serious heat deformation issues as a result. Or the hot plastic may expand and help secure the motor. Or the hot plastic will melt and slip (would have to get REALLY hot), who knows! I'd personally hold off until I see some more convincing numbers.

I think that it's great that people are exploring other designs than the traditional motor mount, but at this stage of development it feel more like 2 steps back, rather than 2 steps forward. Maybe we'll just have to settle for an overall lower performance from the hub motors for the sake of a cleaner design.

777arc   10 W

10 W
Posts: 97
Joined: Nov 04 2014 8:57pm
Location: Blacksburg, VA, USA

Re: Kryptonics Board hub motor

Post by 777arc » Apr 09 2015 11:29am

Hightower wrote:I believe that I use the same $70 motor in my belt driven build as these $200 hub motors and get similar if not better performance. Until the technology gets better, I really don't see any benefit to hub motors. Without any performance benefit over mounted motors, the only benefit to going hub motor is aesthetics IMO. With a mounted setup, after pulleys, belts and the mount, you're getting better performance for a similar price. Adding a VESC to a hub motor would increase it's performance for sure, but it would also increase the performance of a mounted motor as well, so that's a mute point.

If glue is holding the wheels on, it better be heat resistant epoxy or a tight tolerance press fit, because once the wheels get hot from the summer pavement, and your motors heat up from use (there's minimal ventilation inside of a solid wheel)...there may be serious heat deformation issues as a result. Or the hot plastic may expand and help secure the motor. Or the hot plastic will melt and slip (would have to get REALLY hot), who knows! I'd personally hold off until I see some more convincing numbers.

I think that it's great that people are exploring other designs than the traditional motor mount, but at this stage of development it feel more like 2 steps back, rather than 2 steps forward. Maybe we'll just have to settle for an overall lower performance from the hub motors for the sake of a cleaner design.
I paid $175 for alien drive motor mount and pulleys because I can't weld. So that $70 motor is now $245. That being said, I still would not have bought a $200 hub motor if it existed, because I rather gear down my motor for optimal performance at around 10-15 mph. Point is, the money argument does not work for those of us who can't weld. Maybe someday someone will come out with a 70kv motor that works really well, and all of a sudden hub wheels will rock in terms of performance and cost.

Hightower   10 W

10 W
Posts: 68
Joined: Mar 14 2015 10:45am

Re: Kryptonics Board hub motor

Post by Hightower » Apr 09 2015 11:45am

The greatest achievement of Jacob's hub motors over other similar designs is the ability to easily attach them onto any truck or pre-existing board (if there's enough clearance under the deck)

Granted you can't just slap em on and go, you'll obviously still need an ESC, Tx/Rx, batteries, charger, switch, connectors etc etc etc... BUT you'll have the benefit of slightly "less parts"!

Less parts means less things that can go wrong, ideally. Which is very appealing.

torqueboards   100 MW

100 MW
Posts: 2940
Joined: May 27 2013 10:02pm
Location: San Francisco, CA
Contact:

Re: Kryptonics Board hub motor

Post by torqueboards » Apr 09 2015 12:00pm

I like geared setups too :)
DIYElectricSkateboard.com Electric Skateboard Kits

Outgrown   1 mW

1 mW
Posts: 18
Joined: Apr 06 2015 8:06pm

Re: Kryptonics Board hub motor

Post by Outgrown » Apr 09 2015 7:01pm

So hub motors should be for another time once the pros outweigh the cons. With that said, I would like to use my electric cordless drill parts for it; however, I heard that the currents are different (AC/DC) from drills to brushless motors. Would this involve different materials not found in the elongboard kits?

torqueboards   100 MW

100 MW
Posts: 2940
Joined: May 27 2013 10:02pm
Location: San Francisco, CA
Contact:

Re: Kryptonics Board hub motor

Post by torqueboards » Apr 09 2015 9:38pm

Outgrown wrote:So hub motors should be for another time once the pros outweigh the cons. With that said, I would like to use my electric cordless drill parts for it; however, I heard that the currents are different (AC/DC) from drills to brushless motors. Would this involve different materials not found in the elongboard kits?
It's still possible to get it done. It just requires a lot of CNC/Lathe work and testing/modifications. If you want something now belt drive is the easiest way.

You could cordless drill pack but its easier and cheaper to use batteries from HobbyKing.
DIYElectricSkateboard.com Electric Skateboard Kits

Outgrown   1 mW

1 mW
Posts: 18
Joined: Apr 06 2015 8:06pm

Re: Kryptonics Board hub motor

Post by Outgrown » Apr 10 2015 9:55am

torqueboards wrote:
Outgrown wrote:So hub motors should be for another time once the pros outweigh the cons. With that said, I would like to use my electric cordless drill parts for it; however, I heard that the currents are different (AC/DC) from drills to brushless motors. Would this involve different materials not found in the elongboard kits?
It's still possible to get it done. It just requires a lot of CNC/Lathe work and testing/modifications. If you want something now belt drive is the easiest way.

You could cordless drill pack but its easier and cheaper to use batteries from HobbyKing.
Link?

torqueboards   100 MW

100 MW
Posts: 2940
Joined: May 27 2013 10:02pm
Location: San Francisco, CA
Contact:

Re: Kryptonics Board hub motor

Post by torqueboards » Apr 10 2015 10:23am

Link to what?
DIYElectricSkateboard.com Electric Skateboard Kits

Outgrown   1 mW

1 mW
Posts: 18
Joined: Apr 06 2015 8:06pm

Re: Kryptonics Board hub motor

Post by Outgrown » Apr 10 2015 10:58am

torqueboards wrote:Link to what?
Hobbyking materials, if they come in packs then I assume it would be much cheaper.

Post Reply