Joysway UH-1 Catamaran Model number 9112H

[fidelity101]

Is anyone following this thread?

Using West System Marine Epoxy and 104 filler (and some fiberglass cloth and milled fiberglass) I reinstalled the wooden assembly. I also wrapped the bottom of the servo tray portion with thick plastic previously purchased to protect the bottom of my RC Cars. Once the plastic was installed and reinforced, I used a fair amount of the epoxy paste to seal the 4 corners...hopefully resulting in a waterproof box.

Pictures below show the re-installation. Thank you Chris Fine for the 8mm to .250" collet and replacement shaft. The clear plastic tube covering the drive shaft was also replaced with copper tube with a teflon liner. I also used high temp RTV sealant to hold the copper tube inside the stock shaft tube as you can see in the last picture.

For anyone doing research on Joysway hulls in general, this is NOT a 56mm Leopard motor as I previously thought...based on the review of the Joysway Silverline by AtomikRC. I purchased the 56mm battery tray from OSE and it was unable to hold the motor at the correct angle and the back portion would have to be supported with an adapter plate as the stock motor in the Joysway UH-1 measures about 52mm wide by 105mm long. It appears to be a good quality motor, but it's an odd size. Does anyone know how to measure kv of the motor?

[785boats]

One of these should do the trick.

http://www.hobbyking.com/hobbyking/s...earch=KV+Meter

There is also the drill press method. As long as you know the revs of the drill, or can measure the revs with a tach.

1. Drive the motor with a drill press.

2. Measure RPM and voltage generated (by one phase).

3. Kv = RPM / (volts x 1.41 x 0.95)

Good work on the patch up job, bty. Thorough & methodical.

[jaike5]

I Think everybody ran for cover when you mentioned c.f.

Cheers, Jay.

[fidelity101]

c.f. - Carbon fiber? :) I had some cloth laying around and it seemed like a better idea than the fiberglass I had.

Check out the videos of the first run. I went with a new strut, shaft (.250 cut down to .187), shaft tube and prop (452 Octura) which was a perfect match for the stock ESC. I ended up using a swordfish 300A esc because I wanted data recording capability but i think the stock ESC would have worked with the current setup. The previous running gear was horribly out of balance and came with a 60mm prop which would have definitely pulled more amps and probably resulted in overheating or a melt down within a few runs on 8S. The new setup is using a .250 shaft cut down at the end to .187 and a balanced and sharpened 452 Octura prop. If anyone likes data, here is a picture of the graph when powering the Swordfish with an 8S2P 12400mah setup. Overkill for sure, but fun none the less.

Data run on 09132014.jpg

Also, I really didn't notice an improvement in performance when going from 8S1P 6200mah to 8S2P 12400mah and the run times were only about 50% more because because of the increased amp draw (because of the added weight) so I'll probably just stick with 5 minute run times on the 8S1P configuration.

First run: (2 x 4S 6200mah batteries)
Pulling 133A max

https://www.youtube.com/watch?v=m-L7xo5WK2k

Second run: (4 x 4S 6200mah batteries)
Pulling 142A max

https://www.youtube.com/watch?v=B1Oe3oWh2Bc