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

[papertriping]

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

Hey Hummina Shadeeda! Thanks
To be honest I've never worked with electric motors, ESC or Lipos before. Opening up a motor and re terminating seems super complex to me at the moment. I will look it up for sure though! Thanks.

I found this 63-64 190KV motor
http://www.hobbyking.com/hobbyking/store/__39150__Turnigy_Aerodrive_SK3_6364_190kv_Brushless_Outrunner_Motor_US_Warehouse_.html
do u think this will work best for the build?

if i were to run this 190KV motor off 2x3S 5000mah Lipo- what top speed and range(ride time) am I looking at?

would it be 190x6x3.7x0.059x3.1415x60= 46Kph ? (I'm trying to use beto_Pty's equation mentioned earlier in this thread)

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[papertriping]

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.

Well the thing is- the motor mount is intended to latch on to any size wheel- so basically i can use the setup on any longboard. I'm going with the Penny right now- Cuz that's the only board i got (i live in Mumbai, India- Longboards aren't a thing here yet).

So if the whole setup is awkward on the Penny- I can always get a bigger board and have the electric drive system work on that.

At the moment- My number one concern is to acquire all the required components for the build.

 

[Hummina Shadeeba]

I wonder what motor kickr is using with there friction drive. Claims to have "gobs of torque" whatever that is.

The reterminating is mostly done by opening up the motor but I did hear from people at rcgroups.com or somewhere that it can be done as I described with a light n battery. Even if for some reason you didn't find the starts and ends with the battery and make a wye pigtail you could wrap it back up as originally done Get some shrink wrap as well regardless. And a heat gun n soldering iron that gets up to like 730f

 

[papertriping]

I wonder what motor kickr is using with there friction drive. Claims to have "gobs of torque" whatever that is.

The reterminating is mostly done by opening up the motor but I did hear from people at rcgroups.com or somewhere that it can be done as I described with a light n battery. Even if for some reason you didn't find the starts and ends with the battery and make a wye pigtail you could wrap it back up as originally done Get some shrink wrap as well regardless. And a heat gun n soldering iron that gets up to like 730f

the kickr guys have managed to make a video without revealing important details- since its a funded product intended to be mass produced.

Looks like a real tiny motor though

 

[papertriping]

Ok after Exchanging quite a few e-mails with quite a few people- including Hummina and Beto_pty- and a ton of reading and video reviews - I have finally come down to this list of components. (couple of questions I have are marked in blue)

Motor
Sk3 6354 245KV- The Size and weight of the motor fits well in the design. I think I have a chance of getting this friction drive working with this motor (if not- i can always use it on another geared longboard build)
http://hobbyking.com/hobbyking/store/__29497__Turnigy_Aerodrive_SK3_6354_245kv_Brushless_Outrunner_Motor_UK_Warehouse_.html

Lipo
Turnigy 2x 4S 5000mAh 20c Connected in Series= 8s 5000mAh. I choose 8s over 6s- as i think the extra voltage will add to the overall speed- (which will be awesome if I manage to get this friction drive working- if it's too fast- i think i can limit it with the ESC)
http://hobbyking.com/hobbyking/store/__9177__Turnigy_5000mAh_4S_20C_Lipo_Pack.html

How do I connect these batteries in series? what kind of connectors and wire will i need to buy?

Charger
Accucel 6 50W 6A Balance Charger- reviews look great
http://hobbyking.com/hobbyking/store/__7028__Turnigy_Accucel_6_50W_6A_Balancer_Charger_w_Accessories.html

How long would 2x4S 5000 mAh batteries take to charge on this charger? would anyone know?

Charger Power Supply
Hobbyking 105W 15V7A DC power supply
http://hobbyking.com/hobbyking/store/__20971__Hobbyking_105W_15V_7A_Switching_DC_Power_Supply.html

ESC
HobbyKing 150A Car ESC
http://hobbyking.com/hobbyking/store/__10370__HobbyKing_150A_High_performance_Brushless_Car_ESC.html
and Programming card
http://hobbyking.com/hobbyking/store/__10458__Hobby_King_HKSS_programming_card_for_HK_150A_ESC_.html

How does the Lipo connect to the ESC? will i need to buy extra connectors and wires?


Reciever
Hobby King iOS Wifi receiver- i wanna try this for a while before i move to a proper transmitter
http://hobbyking.com/hobbyking/store/__21430__Hobbyking_IOS_Android_4CH_WiFi_Receiver.html

Lipo Charge Bag
http://hobbyking.com/hobbyking/store/__17409__Lipoly_Charge_Bag_14_x_23_cm.html

What do you think about these components? given the design of the Pen E board? Any and all suggestions and guidance is welcome

Thanks in advance!

 

[Hummina Shadeeba]

you've been dissuaded from the low kv!
I've rethought it and I'm thinking:
With a single revolution of an 83mm wheel and the friction drive you'll get 1.3 turns of the motor. Putting the motor up to the wheel and rolling them out shows this or divide. You probably aren't going to use that big a wheel but I think this is the ratio you need to be looking at. Take that 1.3 and with the typical 2:1 gearing on other boards they get roughly 2.5 motor revolutions per wheel revolution. And they're using maybe a 250kv motor. (Actually be better to relate motor revolutions to distance covered on the ground but I'm getting overwhelmed)

Your wheel size doesn't matter with your motor mount but you still can see what these motors like to be spinning at in relation to wheel spinning or ground coverage and and therefore how much torque they can handle. They're stronger when faster. If u undergear it and have not enough motor spin in relation to wheel spin it will be inefficient no matter what size motor you use. Even though a motor may be bigger and (capable) of more power, a powerful motor that's under geared is still under geared and inefficient. You would be less likely to burn up because there's more to burn but still will be inefficient so getting bad range and sluggish, and slow on hills. ironically it's more efficient and quicker with a small diameter motor for your mount. Maybe that's why the kicker motor is so small as u say. It could maybe even be a 40mm. Still think u should retermine it wye and go with the 60mm and 190kv. Or reterminate the 245kv at least. Or go smaller.

Low kv means more torque and a motor that will be happier and more efficient spinning less

maybe you want something not so long as well because with your friction drive you'll want the bottom of the motor to
be taking on as much of the contact as possible since that's where the rotor is supported and the outrunner doesn't have much support.



That mount does look dangerously low
But you can likely raise it

Edited 18 times! And I'm done trying to think and writing at the same time

 

[psychotiller]

This might be considered knit-picking, but your motor mount looks super close to the ground at its lower corner. When it decides to find a rut or bump to anchor itself to it'll be painful.

 

[Hummina Shadeeba]

Use whatever color 10 or 12aug wire for putting the batteries in series just make sure you connect it right

Look at a diagram of batteries in series vs parallel.

You could use those connectors I linked you to for everything I think. I'm questioning if they could go to the motor though but probably so. Ultimately you have to use what connects and can handle the amps as well. Going with bigger wire and connectors is a bit more efficient but likely whatever HK sells will do. If it's getting warm it's too thin. It's most efficient to solder the motor to esc as well as solder your batteries' connections as well. Connectors are the weakest part in the chain mostly. Then you'll only need one plug for everything: plug the batteries (your two soldered to each other) to esc. Make sure the lengths are right

Don't know that charger

I've come to find almost every question is probably more quickly answered with a simple search as so many rc hobby people have asked everything already. For an instant answer in the middle of the night HK has a live chat feature which has always been there for me. Your motor mount friction drive Kv/gearing needs may be harder to find info on though

 

[torqueboards]

I've come to find almost every question is probably more quickly answered with a simple search as so many rc hobby people have asked everything already. For an instant answer in the middle of the night HK has a live chat feature which has always been there for me. Your motor mount friction drive Kv/gearing needs may be harder to find info on though

@papertripping - Lol, your lucky this community is much bigger than it was a while back. I literally devoured all RC youtube videos to get a grasp of things.

 

[Hummina Shadeeba]

Hope I didn't come off rude paper tripping. Just telling my experience. Nice how
Everything from RC is applicable to human sizes! I have no interest in controlling a remote control since I was 13 but with the same knowledge I can make that electric motorcycle.

 

[papertriping]

Hope I didn't come off rude paper tripping. Just telling my experience. Nice how
Everything from RC is applicable to human sizes! I have no interest in controlling a remote control since I was 13 but with the same knowledge I can make that electric motorcycle.

Rude? Of course not- All communication is welcome

 

[papertriping]

This might be considered knit-picking, but your motor mount looks super close to the ground at its lower corner. When it decides to find a rut or bump to anchor itself to it'll be painful.

Yea your absolutely correct. I wanted to be sure so I went ahead and made a mock paper setup (to scale)- so that i could see it on the board rather than in 3D (software).

Here is the problem

This design surely isn't going to work in the real world

 

[papertriping]

Based on what I learned from the Mock setup- I've revised my design for the motor mount

Here's what it looks like this

It has a lot more ground clearance.

The single telescopic arm makes the setup look nice- and still adjustable to fit onto wheels upto 83mm (I guess)

The Red Cylinder represents the Sk3 6354-260KV motor (Diameter 5.9cm, Length (B) 5.4 cm)

I'm optimistic- this design will work well.

 

[papertriping]

Build Update:

Currently waiting for my Hobby King shipment to arrive (it should get here tomorrow)
Also I'm currently identifying the right local Fabricator who can do a good job of the metal work (either Stainless Steel or Aluminum- I dunno i'll leave that up to the Professional fabricator for now)

The Mount design might alter a bit while fabricating- Lets see how all this goes.

I will keep this thread updated

Cheers

 

[papertriping]

Most local fabricators rejected the design- for various reasons. Spoke to dozens of local fabricators- and none agreed. (I think it' odd but anyway). Frustrated, I decided to further simplify the Motor Mount design.

Here's yet another version of the Motor Mount.

With this design i finally found a local fabricator who agreed to help me out with the motor mount!!! Win!!

 

[papertriping]

Level Prototype Accomplished!!!

Behold!

Although it didn't turn out the way I intended it to (some mistakes I intend to rectify with the next version)
It works great so far! The ground clearance seems adequate, and the board rides just like it did without the motor Mount (even on extreme turns the board doesn't rub into the motor at all). Overall the whole setup feels very sturdy and durable.

I'm so excited!!!

Now with the Motor Mount sorted- I'm gonna move ahead with hooking up the electronics!!

Do let me know what you guys think! Any input is much appreciated!

Cheers

 

[papertriping]

I forgot to post this earlier.

My Hobbyking shipment arrived 2 days ago!!

Quanum 2.4Ghz 3ch Pistol Grip Tx & Rx System
Turnigy Aerodrive SK3 - 6354-260kv Brushless Outrunner Motor
HobbyKing® ™ 150A High performance Brushless Car ESC
ZIPPY Flightmax 5000mAh 3S1P 20C
HXT4mm Battery Harness 14AWG for 2 Packs in Series
Hobby King HKSS programming card for HK 150A ESC

Turnigy Accucel-6 50W 6A Balancer/Charger w/ Accessories(Not in Picture)

 

[torqueboards]

Sweet board. Awesome setup. How's the setup run on stop?

 

[psychotiller]

Much better! Good luck on your build

 

[papertriping]

Sweet board. Awesome setup. How's the setup run on stop?

Thanks torqueboards! Coming from you- I'm a bit more optimistic that this whole thing will finally come together and work as intended.

Sorry, I don't know what you mean by 'How's the setup run on stop?'- could you please elaborate.

 

[papertriping]

I want to stick a layer of grip paper /sandpaper on the can of the motor- to avoid slipping- and more so to protect the motor from scratching the ground every once in a while(I've noticed sometimes it does, as I'm still testing the motormount- and my motor can already has scratches on it). I think the Grip paper/sandpaper will help.

What Kind of adhesive should i use to stick the grip paper/sandpaper to the Can of the Motor?
I expect this sandpaper to wear out frequently (due to the friction drive)- needing a replacement every now and then.
Is there some kind of adhesive that sticks paper well to metal- but can be easily removed with a solvent that is safe to use on the brushless Motor? So i can replace the sandpaper whenever needed easily without damaging the motor.

 

[LEVer]

I used this: http://www.surefootcorp.com/index.php/skid-guard/ with my friction-drive board.

 

[Hummina Shadeeba]

you get connectors? Looks like the esc has none. the x90 (or whatever has the anti-spark) are really nice and simple.
the mount looks much better with the two bolts
I wonder how it's going to do having a motor with the kigh kv, big circumference, and no gearing. I thought about it a lot and haven't heard from anyone on here if my feeling that it'll be under-geared is correct.

 

[papertriping]

I used this: http://www.surefootcorp.com/index.php/skid-guard/ with my friction-drive board.

Thanks Pediglide! Nice board btw!- is there a build log for it?

I wanted to test ground clearance on the motor mount- by just riding around with the motor mounted (not powered). I scratched the Motor can a bit when i tried riding earlier this morning

I wanted to avoid this with a temporary fix- so i just wrapped the sandpaper around the motor can with some two sided tape

Looks allright for now- (I dunno maybe two sided tape will melt from the motor heating once plugged in)
What do you guys think? will the heat met the 2 sided tape used between the sandpaper and the motor can?

This is what it looked like after 30 minutes of riding around on the street and testing the mount on diffrent wheels and positions.
The Sandpaper seems to have a more snug fit now from all the spinning. It has a few minor tears from whenever the mount rubbed off the ground - hopefully some protection for the motor.

After riding around quite a bit i finally figured this position for the motor mount works best.

Having the motor on the back wheel this way- allows for the kicktail to be used for tight turns- and the motor never touches the ground or the board on sharp turns.
(I have a feeling once the motor is powered up- having the power on the back wheel wont be very stable- will have to wait and see)

 

[papertriping]

you get connectors? Looks like the esc has none. the x90 (or whatever has the anti-spark) are really nice and simple.
the mount looks much better with the two bolts
I wonder how it's going to do having a motor with the kigh kv, big circumference, and no gearing. I thought about it a lot and haven't heard from anyone on here if my feeling that it'll be under-geared is correct.

I don't have connectors yet- I couldn't get the anti sparks in my Hobbyking shipment. It was an odd issue of total weight of the package. If i added the connectors the package went over the allowed size of 3Kg- so i dropped it from the shopping cart.

Now i'm waiting on some regular 4mm Bullet connectors locally sourced- that should get to me in a couple of days.

I'll sure upgrade the connectors with the anti sparks u suggested when i get the chance.

As for whether the motor will be under-geared- is something we'll have to wait and watch

I weigh 60 Kgs-and going by how smooth the penny board still rides with the motor connected- I think the motor will have enough power. Maybe it wont be able to start me up from a total stand still- But i'm optimistic that with a little kick or two giving the skteboard starting momentum will get this bad boy moving on it own!

I'm keeping my fingers crossed and moving forward with the build