NQD jet boat mod

[gni5002]

I just ordered a tear into jet boat should be here this week. this is the set up im planing on.

motor
http://hobbyking.com/hobbycity/store...idproduct=4195

esc
http://hobbyking.com/hobbycity/store...idproduct=7377

Battery
http://hobbyking.com/hobbycity/store...idProduct=6540

Tell me what you guys think. im definitely open to suggestions!!

[damfurst]

The motor will be too high of kv and will be straining because it just is too small. Some people have tried to use them but usually end up burning them up. Using a 3900kv 24-28mm can will be better on 2s. The best for 3s is 2800kv-3200kv in a 28mm can. The drive in these jet boats require more torque than rpm.

I have ran both 3200kv 28mm heli/outrunner motor and a 3700kv 20mm inrunner. The 3200kv works best on 3s but 2s is the limit on the 3700kv and not really the best.

The rest of your esc and battery look great unless you go to a 3s battery.

[j.m.]

Use this motor:

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=4197&Product_Name=HXT_2445_%28370L%29_2900kv_Brushless_Inrunner

Bigger is better. If you have a bigger motor, it will work less to push the boat the same speed. That means less amps, longer batt life, and less strain on your electronics in general. Not to mention the L can will give you instant acceleration...


Jon

[gni5002]

jon your talking about 3s right

[j.m.]

Sure. The motor would run on 2s, though it would be best on 3s. Im not sure if the drive would work at those speeds.

This would be a better 2s motor:

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=4200&Product_Name=HXT_2835_%28380S%29_3900kv_Brushless_Inrunner

[gni5002]

there in lies the problem hobbyking has a bunch of good motors but there stock is limited

[j.m.]

Because they get so darn many orders!

Just use 3s! With the higher voltage you'll draw less amps for the same output. Remember W=V*A

w= power in watts
v= input voltage
a= amps

Increase the voltage, amps must go down for the same output. That's why high voltage systems are so efficient.


Jon

[gni5002]

yea thats what a couple of my buddies keep telling me. but thanks for the help its much appreciated. i think the new setup will look like this.

Motor

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=4197&Product_Name=HXT_2445_%28370L%29_2900kv_Brushless_Inrunner

Battery

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idproduct=8912

with the 35amp marine speed control

[j.m.]

Perfect.

You might need two smaller batts to balance the boat though. I.e. one batt on either side of the motor/ jet drive.

[gni5002]

you mean a 1s and a 2s pack. can you hook two different s packs together like that?

[j.m.]

No, like two 3s packs in parallel. Say two 1500Mah packs.

[gni5002]

ic that would give me longer run times true

[j.m.]

I mean, you could do 1200's or w/e doesn't add too much weight. You'll have a ton of power with that motor though and you'll want to keep it in the water so the jet doesn't air out too much.

[gni5002]

yea i gunna go with the bigger ones. thanks for all the help jon. i cant for my boat to get here so i can tear it apart and get this setup in it

[j.m.]

Have you worked with fiberglass before? I'd like to see one of these hulls reinforced with fiberglass.