Need some input....

djmeistro

10 µW
Joined
May 22, 2015
Messages
5
Hello! This is my first post. I have been lurking for a little bit and have finally started building my first electric longboard. :D Anyways I needed a little input before I actually purchase my parts. A little background about me is I am a big person (230lbs). I plan on doing a dual rear wheel drive system with custom welded motor mounts.

1. I wanted to decide on the motors: Would two NTM Prop Drive 50-60 270KV http://www.hobbyking.com/hobbyking/...KV_2400W_USA_warehouse_.html?strSearch=ntm 50be sufficient for my weight/ also give me a fun ride? Or should I go with 2x Tacon Big Foot 160 Brushless Out Runner Motor for Airplane (245KV) http://www.hobbypartz.com/96m608-bigfoot160-5335-245kv.html ? Secondary question, if I decided on the Tacons, would I be able to fit two on a single 180mm Paris Style Truck?

2. I was having alot of trouble finding the appropriate escs for either motor options from my first question. Does anyone have any recommendations for the best bang for your buck for either options (keeping in mind cost since it is a dual motor system)? Would the cheap boat escs mentioned in the tutorial posts be ok?

Any help or suggestions are really appreciated!
 
Hey djmeistro,

1. I definitely think the 2 NTM 270kv 2400W drives will be sufficient. That's an almost 7hp board :twisted: .
If you're unsure about the weight you should gear it low. Ideally you'd want to gear at about 1:2,4. When you gear you should never exceed 1:6, it's not efficient/spaceefficient. Besides, I don't think you want to go much faster than 25kph/15mph on a skateboard anyway so I'd say you should aim for that.

When gearing you are limited.
For the small pulley you are limited by the nominal power transfer. If you go for a very small cog (12T) you won't be able to transfer as much power as when you choose a 14T cog.
For the big pulley you are limited by the ground clearance you want, When you have to deal with gravel on the road you do not want that gravel to ruin your belt/pulley. I suggest you get some precision paper and sketch it out or use a cad program to find out how big you can/want to go.

Gearing (for) low (speed) is important because it impacts your acceleration, and accelerating from 0 is the hardest thing you will make the engine do. A DC engine forced at 0rpm while you open up the throttle causes a huge amperage draw that can destroy lots of the electronics. When you gear low you get a lot of the power at lower rpm, so getting away from 0 happens faster and easier. Think about it as trying to bike up a hill from standstill on your biggest gear vs your lowest gear, you want the lowest to get going.

If you are still unsure you can always push kick to start and then use the engine.

Edit: Can you place two of those next to each other? The small ones yes, the big ones no.
This engine is the same size as your big one on a 180mm truck:
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But, this shouldn't deter you to use two big ones, you can put a diagonal drive on your board.
Put one on the left front wheel and one on the right back wheel.

2. You'll have to ask someone else, this is not my expertise.
 
Hei djmeistro,

I'm also in the process of building my first e-board, so I'm definitely not an expert.

> Would the cheap boat escs mentioned in the tutorial posts be ok?

I have the understanding that boat ESC are cheap because they are all water cooled.
If your handy mechanically, you could remove the heat exchanger on the ESC and replace it with a real heat sink.
Sizing the heatsink is a little bit difficult if you don't know the minimum efficiency of the ESC.
I assume that the efficiency on these thing is really good, since the ESC I have is advertised to have a
6.6 kW (12S*150A) capability and has a relatively small heat sink.

Someone who knows what they are talking about should chip into this conversation, but I'd say that a CPU cooler made for a +100W processor should be enough to cool an ESC with the power range you need. A CPU has a thermal efficiency of 0%, all power is converted to heat.
 
Those motors are great, they should be sufficient. I can recommend you have a look at alienpowersystem and aliendrivesystems. They are great if you are unsure on some parts. Both guys are very helpful and I found the esc and motor mounts I got from there to be very good quality :)
 
A couple of people have employed the boat ESC but that's it. Several other people had issues with them. My advice would be to use a proper car esc that is programmable. If you don't you you'll most likely be airborne before you know it.
 
1. I wanted to decide on the motors: Would two NTM Prop Drive 50-60 270KV http://www.hobbyking.com/hobbyking/store/__30784__NTM_Prop_Drive_50_60_270KV_2400W_USA_warehouse_.html?strSearch=ntm%2050be sufficient for my weight/ also give me a fun ride? Or should I go with 2x Tacon Big Foot 160 Brushless Out Runner Motor for Airplane (245KV) http://www.hobbypartz.com/96m608-bigfoot160-5335-245kv.html ? Secondary question, if I decided on the Tacons, would I be able to fit two on a single 180mm Paris Style Truck?

Both motors NTM and Tacon will fit on a dual rear 195mm Paris. 180mm Paris might be a bit smaller. With a bolt on kit they would fit. You might have to space out the wheels as well.

I'm working on a bolt on kit that will fit both these motors on a rear truck. Possibly on the 180mm.


2. I was having alot of trouble finding the appropriate escs for either motor options from my first question. Does anyone have any recommendations for the best bang for your buck for either options (keeping in mind cost since it is a dual motor system)? Would the cheap boat escs mentioned in the tutorial posts be ok?

I would go with VESC although in Beta there may not be any available at all. I would go with the 6S or 12S ESC which I've been selling on my website - might want to wait actually. About end of June and/or early July. I will have full sensored ESCs and Sensored Motors with option for 15mm belts on a dual diagonal and/or 9mm belts on a dual rear.

I would think twice about the APS ESCs. http://endless-sphere.com/forums/viewtopic.php?f=35&t=67998&p=1024965&hilit=alien#p1024965. I have a box of about 20-30 of these and they are all garbage. If you've been around for a while everyone knows these aren't that reliable.
 
I would think twice about the APS ESCs. http://endless-sphere.com/forums/viewtopic.php?f=35&t=67998&p=1024965&hilit=alien#p1024965. I have a box of about 20-30 of these and they are all garbage. If you've been around for a while everyone knows these aren't that reliable.[/b][/color][/quote]
Really? That does surprise me, they do appear to be very well made! I haven't actually used the board much though so maybe that is why I haven't had a problem?
 
12S 150A is a bit more durable. The 8S 120A ESC has many issues and is more prone to overheating. 12S 150A has a much bigger heatsink which helps to resilient the heat + higher rated components.
Looking deep down the firmware is a bit bad as well.

There are much more higher quality options than to settle for those ESCs.

Back in the day that was what was available. Just FYI. Anyone is more then welcome to purchase it. But just be forewarned. :mrgreen:

I'm just going by my own experiences and experiences of other APS customers who aren't happy. Not to say they are not happy customers - I'm sure there are many.
 
Just a follow up... I purchased 2x Turnigy 5000mAh 4S1P 14.8v 20C Hardcase Pack ( http://www.hobbyking.com/hobbyking/...1P_14_8v_20C_Hardcase_Pack_US_Warehouse_.html ) thinking I was going to run the batteries in series to create a 8s pack with a HV ESC. Because of budgeting constraints I won't be able to purchase a HV ESC. With that said, can I use 2 HobbyKing® ™ 150A High performance Brushless Car ESC ( http://www.hobbyking.com/hobbyking/...150A_High_performance_Brushless_Car_ESC_.html ) and connect one battery pack to each ESC separately?
 
djmeistro said:
Just a follow up... I purchased 2x Turnigy 5000mAh 4S1P 14.8v 20C Hardcase Pack ( http://www.hobbyking.com/hobbyking/...1P_14_8v_20C_Hardcase_Pack_US_Warehouse_.html ) thinking I was going to run the batteries in series to create a 8s pack with a HV ESC. Because of budgeting constraints I won't be able to purchase a HV ESC. With that said, can I use 2 HobbyKing® ™ 150A High performance Brushless Car ESC ( http://www.hobbyking.com/hobbyking/...150A_High_performance_Brushless_Car_ESC_.html ) and connect one battery pack to each ESC separately?

You should get either (2) 3S packs and/or (1) 6S pack rather than running just 4S voltage.

That ESC works for up to 6S voltage. 4S to each pack versus 4S to one pack is the same. You can run 4S in parallel for 4S 10ah.
 
The batteries have already been purchased. But you are saying that I can run the battery packs in paralell giving me 10000mah? And I can still connect them both to the 6s rated ESC? and how would the wiring setup be two split the battery packs between two ESCs?
 
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