|Pen E-Board| Smallest E-board ever|Friction Drive|

Hello everybody!

It's been a while that I've had an Electric skate board on my mind and just a couple of weeks ago I found the Endless-sphere forums! The amount of knowledge and experience here is both liberating and overwhelming for a noob like me. But I'm glad I finally found EndlessSphere!

I got myself a penny board
http://www.pennyskateboards.com.au/penn ... urple.html

it's a great skateboard for cruising around in the city- and I think it would make a for a great compact city electric skateboard. and it's the perfect size to carry on aircrafts when i head out on vacations!

So now am thinking of building an electric system like this (KICKR)for my penny board.
(Watch the Kickr Video here- at 1:23- they've used the kickr system on a penny board like skateboard)
https://www.kickstarter.com/projects/42 ... -longboard

Inspired by Kickr this is what I came up with- I call it the Pen E-Board!

More images here
http://pho.to/76vgi
(modelling done to actual 1:1 scale in 3d)

I'm getting a professional I know, to fabricate the Motor Mount.
Besides the motor mount- I need help with selecting the right components for this build.

Here are the components I think will be ideal for this build. Although this is limited by my noobness

Motor
http://hobbyking.com/hobbyking/store/__22036__NTM_Prop_Drive_50_60_270KV_2400W.html

Esc
http://www.hobbyking.com/hobbyking/store/__24565__HobbyKing_100A_ESC_4A_UBEC.html

Wifi reciever (It'll be cool to operate this e- board with my iPhone)
http://www.hobbyking.com/hobbyking/store/__21430__Hobbyking_IOS_Android_4CH_WiFi_Receiver.html

I'm having the most trouble with figuring out which Battery will work best. I want to have maximum range on flat urban surfaces (not much hill climbing- although i think the NTM 50-60 motor has enough torque to drive me up some gentle hills). I was hoping to have a range of about 20 km or bout 12-15 miles- Is this even possible. If so what battery or collection of batteries would make this possible (Note: I weigh 60 kgs/ 132 pounds)

Based on my design- I have a Box that's 16cm Long, 10cm Wide and 6 cm deep/high as seen here
http://pho.to/76vgi (please scroll to the last image)

That's all the space available under the tiny 22" Pennyboard Deck to house all the components needed (Lipo, reciever,esc)

This is the battery i think might work- but to be honest- I'm clueless!!
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=8582&aff=877196

Battery Charger
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=6478&aff=877196

I have a friend coming back home to India from the US this month. I need to purchase all the above needed components right away.
Since I dont live in the US- it's even more important that I get all the right components.

My humble request to any/all senior members- ' Can you please please please!- check the above links and components and confirm if these are the right components for the build'. (I need to know asap- I just got day or two before it's too late)

So i can go ahead and buy all of it in time for my friend to bring the stuff to India.

Thanks guys! in advance
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For those of you interested in looking at the motor mount I've designed- you can here
http://pho.to/76yw8
and here
http://pho.to/76z7g

Looking at everything, I have to say it should work as long as the electronics and battery fit in the enclose you should be fine. It seems to me you have decide to go for a friction-driven wheel due to the constraints present on the Pennyboard. Can't wait to see how this turns out. One issue I can think of is complete power loss or a rock of adequate size interfering with the trucks may cause you to fly off your board. The 50mm motor can do flat roads, but not a hill with a steep grade like I'm guessing 40%. Going to need more feedback beside mine to make a judgement.

Lol it's so funny, I just started a project like this a few weeks ago, my mount will be polycarbonate though and I'm using a cheap walmart board that is about the same size as a penny


I wish you the best of luck

Voodoojar has a great build thread on a little kicktail board: http://endless-sphere.com/forums/viewtopic.php?f=35&t=61479

My advise would be to mount the motor in front of the back truck or you wont be able to use the tail without possibly damaging the motor.

. Ooo it's friction driven direct from motor to wheel. That might slip under load. Write and tell us how it goes.

That battery will get u about 5-6 miles

Make sure all ur connectors go together

https://www.hobbyking.com/mobile/viewproduct.asp?idProduct=61690&utm_campaign=140910.USE&utm_content=4136527857&utm_medium=email&utm_source=EDM

These might be safer bet.

..it goes to your phone! Wow haven't seen that and cheap.

That esc I guess works but haven't heard about it. Looks like a helicopter one . Most use car. Says brakes but wonder about brakes on a helicopter and if the timing is ok? Maybe get the programming card

Cool Idea but unless you really weigh like 120 lbs the 5060 probably will not have the torque to direct drive..
270x6x3.7x.05x3.1415x60 =56 kph
For a 50mm diameter motor (at my weight) to direct drive you need a max of 190kv or so...
the 5060 does not do more than 38kph with me on it (at 3.7v).. this direct drive would be expecting it to go 56 kph...so assuming power weight curves are linear (and they have no reason for being so...) you and board would have to weigh under 128 to pull this off

Im also assuming you have all the slipping/wear issues solved, as these might throw some more tricks into the design...

Maybe go double motor?

beto_pty said:

Cool Idea but unless you really weigh like 120 lbs the 5060 probably will not have the torque to direct drive..
270x6x3.7x.05x3.1415x60 =56 kph
For a 50mm diameter motor (at my weight) to direct drive you need a max of 190kv or so...
the 5060 does not do more than 38kph with me on it (at 3.7v).. this direct drive would be expecting it to go 56 kph...so assuming power weight curves are linear (and they have no reason for being so...) you and board would have to weigh under 128 to pull this off

Im also assuming you have all the slipping/wear issues solved, as these might throw some more tricks into the design...

Maybe go double motor?

Click to expand...

I don't do math but looking at his design it looks like he's effectively got two pulley wheels, one being 50mm wide (the motor) and the other is simply his wheel which has a pretty small diameter. It looks close to a 1:1 gear but the wheel is so small maybe it'd work. Please annotate your math

270x6x3.7x.05x3.1415x60 =56 kph
270kv x voltage x ? (Motor outside diameter?)x 60mm wheel=

I notice you've gone for a rear wheel drive. Is there any particular reason for that? I'm currently working on my own build and am thinking of going front wheel drive, as I've heard good things.

Looks like perhaps better cargo-carrying and better placed (backpack?) lower down maybe?
http://endless-sphere.com/forums/viewtopic.php?f=35&t=19001

Hummina Shadeeba said:

beto_pty said:

Cool Idea but unless you really weigh like 120 lbs the 5060 probably will not have the torque to direct drive..
270x6x3.7x.05x3.1415x60 =56 kph
For a 50mm diameter motor (at my weight) to direct drive you need a max of 190kv or so...
the 5060 does not do more than 38kph with me on it (at 3.7v).. this direct drive would be expecting it to go 56 kph...so assuming power weight curves are linear (and they have no reason for being so...) you and board would have to weigh under 128 to pull this off

Im also assuming you have all the slipping/wear issues solved, as these might throw some more tricks into the design...

Maybe go double motor?

Click to expand...

I don't do math but looking at his design it looks like he's effectively got two pulley wheels, one being 50mm wide (the motor) and the other is simply his wheel which has a pretty small diameter. It looks close to a 1:1 gear but the wheel is so small maybe it'd work. Please annotate your math

270x6x3.7x.05x3.1415x60 =56 kph
270kv x voltage x ? (Motor outside diameter?)x 60mm wheel=

Click to expand...

Hi Hummina
Math is correct.
The final size of the driven wheel is irrelevant, we only care about the perimeter of the driving motor
Revs/volt x volts/cell x cells x perimeter of driving motor x 60 min in an hour

But the driving wheel must be relevant. If the wheel is big it's more work for the motor. More distance to travel per revolution. It's effectively another gear

Hummina Shadeeba said:

But the driving wheel must be relevant. If the wheel is big it's more work for the motor. More distance to travel per revolution. It's effectively another gear

Click to expand...

Nope... think of the wheel as an intermediate gear:
wathever the wheel size is, the translational speed can't be anything else than the motor's rotor tangential speed

made_in_the_alps_legacy said:

wathever the wheel size is, the translational speed can't be anything else than the motor's rotor tangential speed

Click to expand...

exactly right...

So with the direct-drive it wouldn't matter what size the wheel is since the distance traveled will be the same regardless of wheel size and solely is determined by the amount the rotor turns.

I can't get over thinking about the size of the wheel. There's a gearing effect if the rotor is "in-line" with the wheel but since this example Isn't inline but it's edge to edge it doesn't creat any gearing. It's 1:1. Thanks

Maybe if he retermimates the motor to wye he can get his single 50mm motor to get the torque! Could be done outside the motor going strand by strand with a battery and led

Paragon said:

Lol it's so funny, I just started a project like this a few weeks ago, my mount will be polycarbonate though and I'm using a cheap walmart board that is about the same size as a penny


I wish you the best of luck

Click to expand...

Thanks Paragon! All the best to you to!

psychotiller said:

Voodoojar has a great build thread on a little kicktail board: http://endless-sphere.com/forums/viewtopic.php?f=35&t=61479

My advise would be to mount the motor in front of the back truck or you wont be able to use the tail without possibly damaging the motor.

Click to expand...

Thanks Psychotiller!- Yup Voodoojar's board is a lot like mine- super helpful! thanks again!

Hummina Shadeeba said:

. Ooo it's friction driven direct from motor to wheel. That might slip under load. Write and tell us how it goes.

That battery will get u about 5-6 miles

Make sure all ur connectors go together

https://www.hobbyking.com/mobile/viewproduct.asp?idProduct=61690&utm_campaign=140910.USE&utm_content=4136527857&utm_medium=email&utm_source=EDM

These might be safer bet.

..it goes to your phone! Wow haven't seen that and cheap.

That esc I guess works but haven't heard about it. Looks like a helicopter one . Most use car. Says brakes but wonder about brakes on a helicopter and if the timing is ok? Maybe get the programming card

Click to expand...

Hey Hummina Shadeeba!
(pardon me if my questions seem stupid- I'm new to all this and eager to learn!)
-What are these connectors for?
-How could you tell that the Lipo Battery would give 5-6 miles- is this your experience or is there some mathematical formula to arrive at this value (range in km or miles based on motor, lipo and payload)
- What Esc would you suggest I use? Could you link me up to a Hobbyking listing of the preferred ESC for this Pen E board Build

Thanks!

psychotiller said:

Voodoojar has a great build thread on a little kicktail board: http://endless-sphere.com/forums/viewtopic.php?f=35&t=61479

My advise would be to mount the motor in front of the back truck or you wont be able to use the tail without possibly damaging the motor.

Click to expand...

Mounting the motor on the front makes sense- that's what I'm gonna do. Good thing is, the motor mount can attached to any wheel.
here's how the Pen E will look with the Motor mounted on the front wheel. Thanks again Psychotiller

beto_pty said:

Cool Idea but unless you really weigh like 120 lbs the 5060 probably will not have the torque to direct drive..
270x6x3.7x.05x3.1415x60 =56 kph
For a 50mm diameter motor (at my weight) to direct drive you need a max of 190kv or so...
the 5060 does not do more than 38kph with me on it (at 3.7v).. this direct drive would be expecting it to go 56 kph...so assuming power weight curves are linear (and they have no reason for being so...) you and board would have to weigh under 128 to pull this off

Im also assuming you have all the slipping/wear issues solved, as these might throw some more tricks into the design...

Maybe go double motor?

Click to expand...

Hey Beto_pty!!!

There's a lot in what you've said that i'm sure is spot on but sadly i don't understand most of it. I'm sorry i lack a lot in technical know how.
But i'm up for learning it all!!!

Could you please explain the calculation (like you would to a 5 year old).

270x6x3.7x.05x3.1415x60 =56 kph (when i multiply i get a value of 56490.453- i'm missing something here - something up with the decimal- could u please point out where im going wrong?)

Revs/volt x volts/cell x cells x perimeter of driving motor x 60 min in an hour

Which I think is (pls correct me if I'm wrong)

Revs/Volt= Kv (of motor)
Volts/Cell= 1 lipo cell base voltage- 3.7
Cells= 6 (because u have considered a 6S pack)
Perimeter of Driving Motor= Circumference of motor in meters = 0.05xpi = 0.05x3.141

What does this value of 56 kph stand for- is it the ideal speed this motor could drive the board at. how does this relate to the weight the motor will have to carry ( me and the board). Also how does this relate to what battries will I need for maximum duration of running/ range

Please can you explain what do you mean by

'For a 50mm diameter motor (at my weight) to direct drive you need a max of 190kv or so...
the 5060 does not do more than 38kph with me on it (at 3.7v).. this direct drive would be expecting it to go 56 kph...so assuming power weight curves are linear (and they have no reason for being so...) you and board would have to weigh under 128 to pull this off'

What i understand from what you said is that my choice of motor (50-60 Kv270) is not correct.
I weigh 132 pounds and would like this board to be fast and nippy ( 50 kmph or faster maybe! )- which motor do you think I should buy for this build?
-------------------------------------------------------------------------------
[However on another thread u once said-

Re: How to build an Electric skateboard tutorial *free versi

Postby beto_pty » Mon Jul 07, 2014 4:24 am

1. The 5060 ntm is one of the motors i use.. pulls me at 42kph on 6s..i weigh 200 lbs
2. At under 135 lbs the 270 should be nice and torkey... no problem there. You always want to kickstart.. it is easier on your motor and it doesn't look dorky like clmbing on and rolling does.. should be able to go up some fine inclines.]
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In any case you mentioned 190 KV- would this motor work better (63-64 190KV)
http://www.hobbyking.com/hobbyking/store/__39150__Turnigy_Aerodrive_SK3_6364_190kv_Brushless_Outrunner_Motor_US_Warehouse_.html

Would this mean
190x6x3.7x.05x3.1415x60 = 39752.54 (which is 39 Kph i think- since i'm going wrong somewhere with the decimal)

What does this Value mean (39kph) does it mean the ideal speed this motor could achieve with a 6s Pack and given 5 cm Diameter of motor?
Is there any formula to include payload (my weight and the the boards weight) to arrive at an actual speed that I can travel at on this board (I'm sure there is :s)

Could you also tell me something bout the power to weight curve u mentioned and it not being linear.

You said-
'Im also assuming you have all the slipping/wear issues solved, as these might throw some more tricks into the design...'

To be honest- I have no clue what Slipping/wear means- let alone have its issues solved - Please please can you teach me what you mean by this and what i need to do for this design to work well.

My biggest question/doubt/concern at this point is which components to buy

1. Motor
2. Lipo Battery
3. ESC
4. Receiver and transmitter
5. Lipo Battery Charger
6. Any other components I my need.
For this Pen E board Build

I'd like to have a top speed (with me on the board) of 40-50kph (more would be awesome) and as much running time as possible- maximum range (15 km-20km maybe? i dunno if that's even possible.
I'd like it to be nippy and have the ability to climb gentle hills.
Provided the selected Lipo, ESC and reciever fit in a Box that's 16cm Long, 10cm Wide and 5 cm deep/high (thats all the space i have under the pennyboard)

Please can you/other senior members link me up to Hobbyking products for the above list. I know maybe I'm asking too much- but i cant help it- I'm limited by my knowledge and yet absolutely driven crazy by the idea of building my very first e-board- I need all the help I can get!

I need to place the order for all the components so that the shipment will reach my friend in time to bring along to India. If i miss it- I'll have to wait another 6 months or more!!! that sux!! I know!

My apologies for the urgency- but its a fact

Awaiting your prompt response.

A million Thanks guys!!!!

1. A 5065 motor with less than 300kv would work. *Disregard. This is not suitable for a direct drive setup and I personally don't have experience with Direct Drive setups.
2. 2x 3s 5000mah packs would do it.
3. Any 150A Car ESC
4. GT2B from Hobbyking and/or our Wiiceiver http://endless-sphere.com/forums/viewtopic.php?f=35&t=59582

torqueboards said:

1. A 5065 motor with less than 300kv would work.
2. 2x 3s 5000mah packs would do it.
3. Any 150A Car ESC
4. GT2B from Hobbyking and/or our Wiiceiver http://endless-sphere.com/forums/viewtopic.php?f=35&t=59582

Click to expand...

Thanks Torqueboards!

1. U recommend a 5065 less than 300 KV Motor
This is one I found -but its 5060- Its specifications say it has to be used with 6s or 8s setup
http://hobbyking.com/hobbyking/store/__22036__NTM_Prop_Drive_50_60_270KV_2400W.html

Here is a 5065 236 KV motor
http://hobbyking.com/hobbyking/store/__18126__Turnigy_Aerodrive_SK3_5065_236kv_Brushless_Outrunner_Motor.html
But it's specifications mention it needs 10s Setup. Can I make a 10 S setup with 2x 5S 5000mAh?

Is the 50-65 a better choice than the 50-60? What are the pros and cons?


2. Lipo- I found many options for 3S 5000 mAh - which one do u think i should get
http://hobbyking.com/hobbyking/store/__11935__Turnigy_nano_tech_5000mah_3S_25_50C_Lipo_Pack.html
or
http://hobbyking.com/hobbyking/store/__9962__ZIPPY_Flightmax_5000mAh_3S1P_40C.html
or
http://hobbyking.com/hobbyking/store/__9183__Turnigy_5000mAh_3S_25C_Lipo_Pack.html
or
http://hobbyking.com/hobbyking/store/__9184__Turnigy_5000mAh_3S_20C_Lipo_Pack.html
or
http://hobbyking.com/hobbyking/store/__8579__ZIPPY_Flightmax_5000mAh_3S1P_20C.html

They are all 3S 5000mAh- but their cost ranges from 22$ to 45$- i'm not sure why, nor which one is right for me. Could you please guide me here.

Would 2 x 3s 8000mAh Lipo give me more range and ride time as opposed to 2 x 3s 5000mah
http://hobbyking.com/hobbyking/store/__16225__ZIPPY_Flightmax_8000mAh_3S1P_30C.html

Is going for 2x3s 8000mAh better?

3. ESC Will this do?
http://hobbyking.com/hobbyking/store/__10370__Hobby_King_150A_High_performance_Brushless_Car_ESC.html

4. Charger for Lipo.- This is another aspect I'm quite confused about
Which one do you think i should get?
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=6478&aff=877196
or
http://hobbyking.com/hobbyking/store/__7028__Turnigy_Accucel_6_50W_6A_Balancer_Charger_w_Accessories.html

5. Reciever- I'm planning to go ahead with the Wifi Reciever which will let me control motor throttle with my iphone.
http://hobbyking.com/hobbyking/store/__21430__Hobbyking_IOS_Android_4CH_WiFi_Receiver.html
Any thoughts you may have about this?

I just want to finalize this list and place the order on Hobbyking as soon as possible! Please could you support me with a detailed response to this message and the links in it- my humble request

Thanks a million!

Ermmm... I mentioned this indirectly earlier in this thread, but can suggest a board that's longer, long enough to hold extra weight (Yah, I know, weight generally BAD), so rider has *somewhere* to carry a backpack etc (so weight lower down re "stability").

... Just thinking how to make device more "practical", and just not some "high-speed" fun thingee.

Honestly I don't think a longer board is required but you may want to switch the plastic deck for a wooden deck, no one I know would enjoy going at high speeds on a penny (deck is too flexy and may result in speed wobbles)

Ur biggest obstacle I think is since you're doing 1:1 gearing your going to need a super low kv motor. Typically people have a 2:1 or even 3:1 gear for torque. As The motor is now with 250 or even 190kv You'll have a high top speed but not the torque to get there or be able to do any hills. It'll get hot and be inefficient besides being sluggish. A bigger motor will help dissipate the heat but still youll want a lower kv so the motor will be comfortable
I haven't done it yet but still am planning on doing a 1:1 drive so I was researching it a lot myself. Practically all hobby motors are terminated delta meaning the wires in the motor (6 of them) are paired to make your three motor leads. If you identify what individual motor wire strand is going where by finding where they start and end with a led light n battery u can then make a wye bundle and solder half the wires together and then u will now have three half as thick motor leads and one wire thats just the three connected together in a short tail. That will almost halve your kv and its also said to be more efficient and work better with the esc. Reterminating your motor to wye (sometimes called star) will instantly jump you up 10 electronic nerd points

Huminna is definitely right about this one. My first original post is incorrect since you are doing a friction drive setup.