Hull for twin motors?

[znus]

Hi!

My next build will be somthing to play around with in the autumn winds and waves. I have all the hardware I need but I have no luck finding the right 28-33" hull. I'm gonna go with twin motors but I don't want a cat. What I'm really looking for is a pretty flat bottom V-hull.

I need at least 1" between the motors for access to mounting bolts and what not. That makes the shafts ~2½" - 3" apart.

The motors are 2300 kv 3656's and they'll run on 3s with counter rotating flexshafts and 38 mm props. I'm happy with 30-35 mph as the boat is for fun driving in choppy water - not dragracing. Still it's a speed that makes most v-hulls almost balance on it's very last bit of keel and that's where the flatness of the hull comes in. Otherwise the prop's will be completly out of the water.

Any suggestions?

[iamandrew]

youd probably be able to do that speed with one motor on 4S
thought about trying a hydro?

[znus]

Yeah. The speed itself is not where it's at. I have a couple of other FE's with 4074's and 4082's for that purpose. This one will for fun and and I really like the concept of dual motors. Really great acceleration and stability. Not so good in the turns though. Have built a few smaller ones (nqd type) with brushed 600's which I got up to a blistering 25 mph! :-)

[siberianhusky]

Before you decide on a very shallow vee watch some videos of RC Crackerboxes, these are a very shallow hull. I'm not sure about the idea of a shallow vee in wind and waves. Deep vees cut into and through the waves a flat bottom hull will be skipping across the waves and sliding in the turns.
Those Crakerboxes look like the might be fun in the right conditions, could see them being very frustrating as well though.
Thats still a pretty small boat for wind and waves, I'd love to have a basic gas mono about 48" for those days. All my electric boats are 34" or under, the saving grace is our spot is very sheltered from everything but a wind right out of the north.
I think you'd be happier with a larger twin cat than a twin mono, unless you prop down further and run a sub surface drive on a deeper vee hull.
Also remember you won't see much if any more top speed with a twin setup, maybe a little less amp draw and quicker acceleration, but this is usually offset by the extra weight of two of everything and added drag.

[znus]

With waves I'm thinking of 5" chop at the very most. Still enough to go airborne but...well... that's fun in its own way

Yep, I know I won't get 2000 watts of speed with two 1000 w motors mounted in parallell. I get two 1000 watt motors performing with more ease and maybe with a bit larger props compared to a single drive.

I just like the concept of dual motors and I already have all the parts. Dual 3650 (they're 3650's - not 3656 as I wrote eralier) watercooled motors, dual watercoold 150 A esc's, flex-axles coming out of my ears, stingers and shaftholders in a big pile, plenty of counterrotating props etc. etc.

But you're right. Maybe I should go sub surface in a 28-30" deep vee..... hmmmm..... I'll miss the mighty roostertail from twins though

[carlcisneros]

go with ahull at least 40 inches.

mine is a 45" hull and twin outrunners.
even it has a time with about 3" chop at the lake.

dont go shallow v bottom, go for DEEPER V bottom.

thats the one in my avatar

[Jacked1]

If you can find an old Prather deep-vee or something similar you will be pretty pleased for choppy water. I run all my boats on a pretty big lake that has a lot of days where the waves are in the 10" range and I have only flipped mine a handful of times in 10 years. I also really like multiple motors!

[Rumdog]

A flat bottom mono is not wood in chop

[znus]

@carlcisneros. I'm thinking a 40" hull is way too big for 3650 x 2. Your 45" twin outrunner probably is a tiiiiiiiiiny bit faster than my future boat.

@Jacked1. I'd love an old Prather hull but I live in Sweden and those things never found their way over here (to my knowledge)

@Rumdog. Not sure I follow you?

[carlcisneros]

you might also check around to see if you can located an old Dumas Scarab or 60 size comp. Deep V.
Maybe even and Aeromarine challenger.