Electric Mountain Board help please

[AAAkings]

So I will be making a 2WD electric mountain board (Thanks to HumboldtRc as that is what got me interested). The difference is that this will mainly be used on flat ground and not used for too tough of off-roading. I looked at the RC engines but have come to the conclusion that they may not be the best option for my project. I have come across a motor that I believe can be used (correct me if I am wrong) it’s a 450W Brushed motor http://tncscooters.com/index.php?route= ... duct_id=56. I figure that two of these should be able to work for my goal of around 25mph. Now I really like the idea of using this motor opposed to the RC ones due to their intended purpose is to move a person of my size (180lb) as well as how cheap controllers are for them. (Will be using disk brakes as regenerative braking will require a more expensive controller). This is the controller that I plan on using (http://tncscooters.com/index.php?route= ... uct_id=180) or else (http://tncscooters.com/index.php?route= ... uct_id=179) if the second one will work, it will give me about $20 more to spend on the batteries.

What I am stumped on right now is what would be the best option for batteries given the current set-up? Looking for a run time of around 30-45 mins if possible or around 8 miles. I was wondering if I could run 7S LiPo packs with this setup which over volts it to I think 26.6V? Or is there a cheaper option (If it is much cheaper I can find a place to store larger batteries if needed)?

[HumboldtRc]

Fail...The Turnigy sk3 6364-190kv motors will handle at least 1200 watts constant. The only reason they got so hot on my first test ride, was I had my mountainboard geared to 39 mph and I was climbing a steep 3/4 of a mile dirt road. I was probably pushing 2000-2500 watts constant, on each motor, for about 4 or 5 minutes.

[sk8norcal]

here's one with 4 brushed motors...
cant find the thread on here..

[AAAkings]

I figured there was a reliability issue with them aas you stated you fried around 10-15 of them. Though you did mention you left the gearing the same, that the top speed was 38mph, but either you forgot to post you were going up hill or I misread. (Sorry if i offeneded you, there was no intention). But as you said you would wait till the new larger SK3 motors become available, but at the moment I don't really have the time to hope they come soon so thats another reason why I am looking at the brushed motors.

I was actually in contact with that guy there sk8norcal and he was the one that recomended going to a bigger motor and overvolting them to get a bit more power. Now I did find another motor (600W) that I should be able to make fit with a bit of modifications. (http://tncscooters.com/index.php?route= ... uct_id=336) I am just wondering if I were to want to go to LiPo in terms of battery what would I need in terms of setup for about 8miles of run time? Would I be better off looking for SLA batteries.

[HumboldtRc]

I never had mentioned I was going up hill on the test ride (on the sk3 motor thread). Also I fried 10-15 of the old sk motor's, these new sk3's have fixed basically every issue I had with the old sk's. I just need to gear it a little bit slower then with the bigger, old sk motor's. If you want to have your mountainboard geared at about 20 mph you could probably even use 2 of the 50mm sk3's and it will last longer then shity brushed motors.

Here is a video of my buddy and I doing donuts and wheelies.



If the video doesn't work here, try these links

http://www.surfingdirt.com/forum/showpost.php?p=61692&postcount=30

http://www.youtube.com/watch?nomobile=1&v=kaVuh6AG3YM

[addicted2climbing]

Humboldt RC,

Have you tried the new SK3 motors yet? I gave up waiting and bought Aolean 6354 250Kv motors from leaders hobby and am integrating them now. If I have problems I can always buy the SK3 and curious if you know if the hole pattern is the same between the SK3 and older versions and maybe even the Aolean. The Aolean's mounting pattern is 4 ea M4 on a 44mm Dia Bolt Circle.

I learned a lot from reading your posts on the HK forum and I am learning a lot in this forum as well which is helping me to complete my board.

AAA Kings,

That motor is huge... even if it were suitable, would you be able to even fit 2 between the trucks.

Marc

[AAAkings]

OK, so HumboldtRC, two Turnigy Aerodrive SK3 - 6364-213kv should work for my required use right? Is there another comparable brand/motor you would recomend instead?

Also, I realize that the controllers are more expensive than those for brushed motors, but if I don't need the option to have the motors act as a sort of brake, should I still look at the Car ESC rated at 150Amps? (And should I have a 140 or so Amp fuse before it connects to the ESC to prevent burning the ESC like what happened with yours?)

[HumboldtRc]

OK, so HumboldtRC, two Turnigy Aerodrive SK3 - 6364-213kv should work for my required use right? Is there another comparable brand/motor you would recomend instead?

Also, I realize that the controllers are more expensive than those for brushed motors, but if I don't need the option to have the motors act as a sort of brake, should I still look at the Car ESC rated at 150Amps? (And should I have a 140 or so Amp fuse before it connects to the ESC to prevent burning the ESC like what happened with yours?)

The lowest kv motor's are the easiest to gear down. Other wise you end up with a tiny 9 or 10 tooth sprocket on the motor. I am going to use a 15 tooth on the 6364-190kv sk3's and I have 55 tooth sprockets on the tires. It should go around 25 mph with that ratio and motor. If you are going to use front disc breaks, the you can buy cheap 190-200amp HobbyKing SS esc's, I really liked them on my pit-bike. I had 2 of them and 2 6364-280kv sk motor's. The esc's worked great the would never lose sync (in my YouTube videos I had a different set-up on it, when it was loosing sync). The 190-200 amp esc's wouldn't lose sync because they could always dump as many amps as the motors were trying to pull. I had it geared to 25 mph and the esc's barely got warm. But you would have to have to use both hands to have a dissc break set-up and have a throttle, which leaves you no arms to balance with. I tried it on my very first set-up it sucked using both hands. I would recommend using the 120amp HobbyKing car esc's, they work pretty good and are only 40$ and are in stock in the USA warehouse. They will lose sync if you are really hard on the throttle. Or you can use the Trackstar 150amp esc's which never loose sync but are about 70$ and only in stock in the china warehouse. For your application I think either will work fine.

[AAAkings]

Thamks HumboldtRC, the 190's are out of stock atm, but would the 213's be low enough? I guess your right in terms of the balance thing, so I figure I should use a car esc. I noticed you added external hall sensors at one point. Would you recomend doing that again or is it not worth it?

[EDS]

HumboldtRc, did you ever try using the brakes on the SS190? I never figured out what was the difference between airplane ESC brakes vs car ESC brakes so I just went with the 150A car ESC to be safe.

[ohzee]

wow those boards sure look fun. nice videos

[AAAkings]

The boards are unreal. Definatly a work of art!

But HumboldtRC or anyone for that matter. I am ready to make a purchase for my motors/controllers and am wondering if someone could take a look at what I plan on ordering and offer feed back.

Motor (http://www.leaderhobby.com/product.asp? ... ocation=HK)
ESC (http://www.leaderhobby.com/product.asp? ... ocation=HK)

I am pretty sure the motor will be sufficient for the intended use it is just the ESC I am worried about. I live in a relitivley flat city so I don't plan on bombing up any hills so I dont think the 150A ESC is necessary, but I could be wrong (and if so help would be appreciated).

[Uvedovle]

Hi guys!

I found you after some time thinking in make my own e-mountainboard, i already ride a lipo e-skate like mobo and feel like need at least a 2W for improove riding, also want something lighter...
You all have done a good research job here guys, thanks, it's quite helpfull and really apreciated!!

Now some questions about batt, i readed many info but i still not clear about this:
Do you think is possible to use my 36v 15a lipofe4 batt with this ESC using something like http://www.powerstream.com/dc-36V-5V.htm

I couldn't find any rc powerconverter as huge as this, and i really want to still using my lipo; if it not possible, please, point me to find battery and charguer please.

Motors
http://www.hobbyking.com/hobbyking/stor ... Motor.html

ESC
http://www.hobbyking.com/hobbyking/stor ... SC%5F.html

Remote
http://www.hobbyking.com/hobbyking/stor ... em%5F.html

Receiver
http://www.hobbyking.com/hobbyking/stor ... Ch%5F.html

Watt Meter
http://www.hobbyking.com/hobbyking/stor ... duct=10777


Some friends are going to help me about syncs, timming, and all i read in your posts and can't understand yet (dumb mode on)

Next step is to find the perfect gear for the motor, its my firs rc job, i don't really know how powerfull can be the motors, i just hope get better drive than mobo skates.



I

[Uvedovle]

Come on guys! Help us please!

[EBJ]

Come on guys! Help us please!

There really aren't that many guys on here that go for the skateboards.
Those that do have already posted their build-threads. Most use hobby-king RC parts as it seems you are already doing.
So there really isn't much for anyone to tell you,
and my advice would be to just search the other build-threads.

[Uvedovle]

Come on guys! Help us please!

There really aren't that many guys on here that go for the skateboards.
Those that do have already posted their build-threads. Most use hobby-king RC parts as it seems you are already doing.
So there really isn't much for anyone to tell you,
and my advice would be to just search the other build-threads.

Thanks, hopefully these guys who made allready e-skate post some help.

Wbr

[AAAkings]

I will have to agree with EBJ. There hasn't been too many people on here that have modified skate/mountain boards. There are two that come to mind instantly when I think about it and that is HumboldtRC (Sorry if I spelt it wrong) and Addicted2Climbing (Again, sorry if I spelt it wrong). Both of them seem to have answered any questions I had for them and Marc (Addicted2climbing) is still building if I am correct. And there is also another member on here that has a build log on another site, his name is Christian and his log has a description of everything that his board has. If you want the link let me know, but again, the two names listed above were very helpful when I had questions and I would recomend asking them questions. (Be sure to read through all 50 something pages of HumboldtRC's build log on hobby king as it answers a lot of questions.

Just my 2 cents of rambling. I will be doing a full build log once mine is finally finished, just taking a lot longer than I had expected.

[Uvedovle]

Thanks AAAKings, i had problems for reading HobbyKing forums, now its seems to be ok. I readed a lot already, but now i'm going to read complete thread from begining.

My main question is about using my 36v 12a lipo with this.


Wbr

[nieles]

Now some questions about batt, i readed many info but i still not clear about this:
Do you think is possible to use my 36v 15a lipofe4 batt with this ESC using something like http://www.powerstream.com/dc-36V-5V.htm

so if i understand you correctly, you want to convert the 36v to al lower voltage (15v?) and then feed the 15v to the esc.

i have never seen this done before, so there is probably a good reason for that.
one reason i can think of is the efficiency of the dc-dc converter (70-80%)

the dc-dc converter you linked to is just an example right?
if not.. 60w will not be enough

i would either go for one of these options:
1. go to a 6s lipo battery
2. go to a lower kv motor and different controller (36v capable)
3. double your reduction and use same motor, but different controller (36v capable)

do you need the brake function part of the controller? that would limit your choices.

[Uvedovle]

Thanks Nieles! This is the kind of help i need


You just pointed me in the right way, i will buy new lipo battery.

I want ESC able to reverse and brake if possible, and capable to work with these turnigy with low Kv. Is possible to do with sensorless esc and motor?

My main question now about motors its about sensorless motors and esc's; i readed but i can get what is better for me, i think sensorless is ok...

As i wrote before, i'm noob in rc, i don't know how to wire receiver with esc's (not really worried about it), i just need someone tell me if the parts i posted before are fully compatible, then i'll buy it and try to make ir work , i'm good in electronics, i hope don't have many problems in it.


Thanks for your help!

[nieles]

i have no direct experince with those controller from hobbyking.

af far as controller choice, i would go with this one:
http://www.hobbyking.com/hobbyking/stor ... r_ESC.html
this controller can do both sensored and sensorless.
so you can start out with sensorless, if you are not satisfied you can always switch to sensored
(ofcours you need to install sensors in/on your motor then)
burtie (a member here) has a optical sensor kit for sale, that could be used in stead of the normally used hall sensors

you should check out this youtube channel:
http://www.youtube.com/user/HumboldtSto ... ture=watch
this guy is on this forum too. (humboldtrc i think)
you could ask him some questions on one of his threads

also on you shopping list;
the transmitter already comes with a receiver, so you dont need to buy a seperate one

the wiring of the system is fairly straightforward. the controller has 5 power wires. red/black for battery. blue/green/yellow for the brushless motor.
there is also a small connector with 3 wires. this is the signal cable, and also powers the receiver. you need to plug this cable in to the receiver channel 1 or 2 (not sure, one will be controlled by the steering wheel, the other by the trigger). if the motor turns the wrong way, just swap 2 of the 3 motor power wires. thats all for sensorless control.

[Uvedovle]

Thanks a lot! Now, let me get some cash for spend in this crazy monster.

Wbr

[AJChuckles]

Nearing the end of the year, the project is wrapping up. All that is left to do is to make a carbon fiber plate, and finish clearing the electrical housing compartment and break the chain to the correct length. The motor mounts are complete and differ from my original plan but should work for what they are. I will post more pictures and a complete build log as soon as everything is complete and the report is finished. But for now a glimpse of what it looks like now minus the motors. Board design is based off of one of Cindrich's longboard with a few tweaks. Anodizing/dimondyze and powder coating was completed with the help of Hupe Mfg.

P.S. Thanks to everyone on this forum for all the valuable information available to the noob's like myself.

[sk8norcal]

looks great,
is AAAkings and you working on this same board above ??

viewtopic.php?f=35&t=31945&p=513806&hilit=flexboardz#p513806

[EBJ]

love it!.

but how do you plan on putting grip-tape or bindings on it ?