BBY Micro Scat Cat - How to keep it on the water?

[chipgibbs]

20150704_141755.jpg20150704_141755.jpgBack Story: I bought a Hobby King Centurion brushless tiny boat to play with. It fits in a backpack, costs $109. and if pretty fast right outta the box.

Problem with the Centurion is it's very narrow and the hull is paper thin fiberglass. After hitting a submerged stick, The transom was toast so....

I found the Micro Scat from BBY Racing. it's an inch longer & wider than the Centurion...perfect and only $30 for the hull.
I transferred the hardware & motor and took it for a maiden thinking it would perform at least as good as the Centurion. It is soooo fast I can't keep it on the water. I tried raising the strut and changing the prop angle but it's still kinda scary. And it does this instant flip thing. In a slow turn, it will get around about 3/4 the way round and suddenly flip over.

Anyone got any ideas on how to tame this rig?

Chip

[Heath M]

Details of the set up would help.
you could try moving the cog more forward for starters.

[chipgibbs]

This is a 16" X 6.5" boat running a 24-45 3000kv brushless w/ 30 amp ESC & CNC 30mm prop on 3S 2200 lipo.
I used the strut, drive tube, motor mount etc. from the Hobbyking Centurion. The rudder is a Chinese ebay find which I extended to just behind the prop on the right side.
I will try to get a strut & CG measurement this evening.

Chip

[Heath M]

You could also try a slightly smaller prop, 27mm. Also angle the back of the strut down slightly, this will help to keep the nose down.

[chipgibbs]

Got the measurin tools out and did some checking. Nothing too weird that I can see.
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Could the Rudder be too deep?
BTW, the pencil mark in the ruler photo is where the boat is balancing.

Chip Gibbs

[Heath M]

Cog wants to be between 30 - 33% of the wetted length.
As mentioned earlier also try angling the back of the strut down alittle so it keeps the nose down.

[z400]

That is a cool little boat!

[chipgibbs]

Moved the CG forward. Had to elongate the strut slot for more up down adjustment. Raised the strut a bit & angled down. Still a hand full but, stays on the water better.
The weird turning flip thing is still there. I'll try to get some video of it in the future.
This is a great tiny backpack boat.

ChipG

[chipgibbs]

Can I use Marinetex to blue print this plastic hull? Will it stick?
This is a vacuum molded plastic hull. Not sure if it's ABS or some other type material.
thanks for any advice

CG3

[Heath M]

Its ABS plastic, i just used builders bog or car bog on mine.

[ls1fst98]

Could the hull be flexing in a turn? Causing some strange sponsons angles?

[Heath M]

Doubt it, but the rounded edges could have some affect. Make sure they are all square and sharp when you blue print the sponsons.

[flraptor07]

I would get a hold of Randy at BBY Racing, I'm more than sure he could tell you how to set up his boat. He's on the forum RandyatBBY http://forums.offshoreelectrics.com/...459-RandyatBBY