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        Discussion Unofficial NQD Tear Into Jet Boat Mod Thread

#1 Energy Mar 11, 2011 10:21 AM

Unofficial NQD Tear Into Jet Boat Mod Thread
 
I know that there are a small group of guys running this boat here, so why not make a "go to thread" for pictures, video and talk.

http://www.gorcgo.com/image/cache/da...-1-500x500.jpg

#2 Energy Mar 11, 2011 10:25 AM

I'm going to be running this set up in mine.

Motor

ESC

Lipo

servo

#3 eak Mar 11, 2011 10:33 AM

you get the motor at half the price if you get cooling jacket and motor as 2 items.
Cooling jacket was out of stock as the motor you picked ATM

#4 Energy Mar 11, 2011 10:59 AM

Quote:

Originally Posted by eak (Post 17651318)
you get the motor at half the price if you get cooling jacket and motor as 2 items.
Cooling jacket was out of stock as the motor you picked ATM

Good to know, i just hope either of the two come in soon, so i can get going with this mod.

#5 Mikedown Mar 11, 2011 11:03 AM

jet boat
 
Go to universe site which has a huge thread and the top gurus there and will take you all day to read it and are SUPER HELPFUL.:D energy, remember there isn't much room, i have one and the kv you have is too high. The impellor won't take that high a rpm. BTW, i just was reading post #12 about high rpm which spins too fast to create suction. Now if they plan on running high rpm, better put in bearings and buy another prop or two of them as they will wear very fast. Now if memory serves met right; Dragonfire cut down a metal prop for his jetdrive unit.

#6 Energy Mar 11, 2011 11:20 AM

Quote:

Originally Posted by retoabcr (Post 17651578)
Go to universe site which has a huge thread and the top gurus there and will take you all day to read it and are SUPER HELPFUL.:D energy, remember there isn't much room, i have one and the kv you have is too high. The impellor won't take that high a rpm.

There are a few guys that have reported running this motor on 2s with no issues. On 3s it would be way to much, but with 2s its supposedly perfect.

I'm subscribed to the RCU one, but RCG has some good info too, its just that its scattered throughout many little threads.

#7 eak Mar 11, 2011 11:22 AM

http://www.hobbyking.com/hobbyking/s...dProduct=15190
Maby this one fits you? I don't know how much room there is, and what max rpm that jet drive can manage.

#8 Energy Mar 11, 2011 11:24 AM

Quote:

Originally Posted by eak (Post 17651748)
http://www.hobbyking.com/hobbyking/s...dProduct=15190
Maby this one fits you? I don't know how much room there is, and what max rpm that jet drive can manage.

Cool, Maybe with this jacket... http://www.hobbyking.com/hobbyking/s...dProduct=12689

#9 Firehawk989 Mar 11, 2011 11:29 AM

Yea that kv motor on 2S should be fine, and there is lots of room in the hull because it is so wide. Plus with that motor you will be able to use the stock coupler which is nice. The ESC is the exact same one I'm using and it works great, although I'm running it on 3S.

That setup might not be the fastest, but it should be pretty reliable I think.

*Edit* Be aware that you only need about 5mm or so of servo travel to move the jet nozzle to full left and full right, so you might have to turn your dual rates way down or drill a hole very close to the center of the control horn for that big servo.

#10 eak Mar 11, 2011 11:31 AM

if you buy that combo its about half the price of the 28mm premounted watercooled engine that they sell. you can also make your own jacket with plastic tubing and o-rings, and some small bras or coper pipes and some good glue.

#11 Energy Mar 11, 2011 11:40 AM

Quote:

Originally Posted by Firehawk989 (Post 17651825)
Yea that kv motor on 2S should be fine, and there is lots of room in the hull because it is so wide. Plus with that motor you will be able to use the stock coupler which is nice. The ESC is the exact same one I'm using and it works great, although I'm running it on 3S.

That setup might not be the fastest, but it should be pretty reliable I think.

*Edit* Be aware that you only need about 5mm or so of servo travel to move the jet nozzle to full left and full right, so you might have to turn your dual rates way down or drill a hole very close to the center of the control horn for that big servo.

Thanks.

I have a DX2s, so i can just program servo end points. Good to know!

I just got the stock battery charged up, and am going to go run it in a little stream. May as well get some use out of it while i wait for upgrades to come in. :)

#12 wparsons Mar 11, 2011 02:01 PM

4800kv on 2s is beyond what the drive is useful for. Small jet drives don't do much besides cavitate if you start spinning them more than 25000rpm. That motor on 2s would be over 35000rpm unloaded. I would aim for a motor in the 3200-3600kv range for 2s. I have a 3200kv outrunner in mine on 3s, and over 3/4 throttle is jut makes more noise without picking up any speed.

The servo is also overkill, I run mine on an HK 9g servo with no issues at all.

#13 Energy Mar 11, 2011 02:55 PM

Quote:

Originally Posted by wparsons (Post 17653129)
4800kv on 2s is beyond what the drive is useful for. Small jet drives don't do much besides cavitate if you start spinning them more than 25000rpm. That motor on 2s would be over 35000rpm unloaded. I would aim for a motor in the 3200-3600kv range for 2s. I have a 3200kv outrunner in mine on 3s, and over 3/4 throttle is jut makes more noise without picking up any speed.

The servo is also overkill, I run mine on an HK 9g servo with no issues at all.

Hmmm, Its not that i don't believe what you are saying, but there are two or three guys over on RCU that are running this exact set up (minus the servo) and say it works fine. I don't think there will be a torque will be an issue, so i guess if its too fast for the intake, I'll set a throttle end point.

Ya, the servo is a little over kill, but I was recommended at RCU to go bigger servo than a mini. I'd rather overkill then under-kill. :D

#14 Energy Mar 11, 2011 03:06 PM

Stock NQD Tear Into jet boat (2 min 10 sec)


Just uploaded a stock video. There was about 4 inches of slush, but still kind of cool.

There are these great little pools on the surface of the ice caused by the snow melting. Would be fun to have a moded one in them.

#15 wparsons Mar 11, 2011 03:30 PM

Quote:

Originally Posted by Energy (Post 17653612)
Hmmm, Its not that i don't believe what you are saying, but there are two or three guys over on RCU that are running this exact set up (minus the servo) and say it works fine. I don't think there will be a torque will be an issue, so i guess if its too fast for the intake, I'll set a throttle end point.

Ya, the servo is a little over kill, but I was recommended at RCU to go bigger servo than a mini. I'd rather overkill then under-kill. :D

IMO, I wouldn't set the throttle end points to bring the throttle down, running brushless ESC's at part throttle generates a lot of heat.

The issue isn't torque, it's the WOT rpm's are too fast for the small jet pump to handle. Going with a lower kv motor will give you just as much performance, and at the same time keep the heat and amp draw lower.

You can run as big of a servo as you want, but I haven't had a single issue with a cheap 9g one. The only benefit to the bigger one is that it would add weight to the boat (they like to be a bit heavier to keep the intake in the water). If it were me, I would build it light then add stick on lead for ballast in key places though.


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