54" brushless cat questions

[arizona82]

Planning to build a 54" Central R/C Mystic. Want to use dual motors, esc's, drives, etc. for scale looks. Not looking for a speed monster, 50-60mph tops. Would like to know what kv and cell count you guys would recommend for using some 5 blade props, again for scale looks. Not sure what pitch props to get either. I know prop shop has a big selection. My main concerns are scale look, handling, and run time. It'd be nice to go 10 or 15 minutes. Thanks.

[Make-a-Wake]

Twin Leopard 4092's in the 1400-1600 kv range on 6s each will get you to those speeds. The 1480kv would be great..............

[arizona82]

Any suggestions on where to start on props? Propshop has a ton of 5 blades.

[Make-a-Wake]

I wish OSE carried an x452/3 in both rotations, thats what i would suggest. You can get x450's in L + R rotation in the 3 blade. You may be able to use x457/2's which come in both rotations as well. If it were me i'd try the x450/3's.

[arizona82]

Going to use 5 blade props because they look like the real deal.

[iamandrew]

Do not use 5 blades,
they cavitate and do not scale down.
youll get a lot of vibration and the blades will crack, or damage the entire drive line

* actually if its a 54in hull, 5 bladers might work!

[madmikepags]

5 blade props are a real pain to sharpen and balance, and not many people have info on how to prop motors with them, so probably start out with some 2 and 3 blades and work from there, a 5 blade prop same pitch as a 2 blade would need to be much smaller than the 2 blade to get the same amp draw. I personally wouldn't even know where to start w a 5 blade?

[nata2run]

Al might be your answer http://forums.offshoreelectrics.com/...h-Voltage-quot
One would think the current draw would be high so runtime would suffer, maybe the right props for driving and 5 blade for show?

[Make-a-Wake]

As noted here, 5 bladers are mainly for show, they dont work well with RC boats, you could put them on for show as mentioned. I really think the Octura x457 2 blades will make her rip. 5 bladers are very expensive, cavitate and are brittle.

EDIT* I have an x460 3 blade that is chrome and beautiful, but it runs worse than the berylium version, so I dont run it, I will put it on if I ever "show" the boat.

[arizona82]

Als boat is waaayyyyy over built. But, that's one of the things I like about it. My boats gonna see some big water. :) Looks like I'm going to go that same direction. He's pretty much dead on the numbers I'm looking for. Might go 900 kv on 8s. His theory was 600kv on 12s is like 1200kv on 6s. Split the difference. Can't believe the runtime he's getting, 10-15 minutes...that's what I'm after. 100mph is great, but changing batteries every 2 minutes seems a little silly to me. Would rather do 60 for 15 minutes myself and actually get to use the boat.

[nata2run]

60mph for 15min is going to be sceince or require some large heavy packs 5 blade will load up the motors small props and big motors will keep the draw down and get you long runtimes

[focused]

54" cat , 2x scorpions 4035/800 each on 10s with 2 x457 downsized to 54mm good for 60mph . I have the same setup in my Drambuie on Ice 54".

[arizona82]

Decided to go gas power. Just about the same $$$ as motors and esc's. And a whole lot less $$$ and work than batteries when you're at the lake. Also decided I'm not wild about havng 60-100 volts in a water toy.