John Vennerholm

Building a 28", 4.75 lb. scale displacement hull model of old Menhaden fishing trawler for a friend.
Need recommendation for powerplant with single screw setup with one 2" - 4 blade prop to give best scale wake speed of original 250 ft, narrrow beam 250 HP ship from 1890-1930 era. This model will run on 7.2v.NiMh.

I've scratch built my own 40" English ferry boat on 3S Lipo with two Viper 15 amp marine controllers and two MFA Torpedo 500 - 6:1 geared with a pair of 1.25 dia four blades that sails fantastic. Scale wake speed is at 1/2 throttle. At 84, I'm finally getting out of unlimited sailplanes and down to earth (water ??---) and it was my first.

My next will be a 32" RIVA Aquarama and I'd appreciate advice on its powerplant too. It will be a twin. This will emulate a 38 foot, 900 HP original and I'd appreciate guidance here too.
Thanks

All Day Dan

My Feedback: (5)

Maybe you can pick up some ideas from this thread. Dan.

http://www.rcuniverse.com/forum/rc-s...l#post11009591

John Vennerholm

Dan,
Good info. Should make your PT really scat and a similar rig will do just fine for my RAVA Aquarama. (Fastest full size one specially built had two Labborghini twelve cylinder engines in a 38 foot boat. You should see the video - scary!
Stilll looking for a powerplant suggestion for my old (slow) Menhaden Steamer model. It's to be built by a professional class mantle scale craftsman who I;m trying to get into RC for a first time. He'll use a basicTraxxis setup with no frills.
Merry XMAS
John

dunworkin

My 34" unfinished Menhaden Bunker Boat is powered by a Speed 500 direct drive. A little overpowered & running on 6 volt SLA battery. Narrow beam keeps you honest with your speed and ballast placement.

blizard05

Take a look at the motor and ESC for the tugster, from Zipp Kits. I have used motors from old cordless drills in some of my boats

mfr02

A stock (cheap) 385 size motor on about half its rated voltage via a 2 or 3 to 1 gear or toothed belt drive. Small, not particularly fast boat with a large prop needing torque.

canabus

HI John
As for the 32" RIVA Aquarama a couple of 28mm brushless motors(EG B28-57-17L 1700kv 630 watts) with 45 Amp brushless ESC's on 32mm x 1.4 pitch props.
Two Lipo batteries 2650mah 30C.
This will give you a good 1/2 to 3/4 hour run time.

mfr02

The numbers suggest almost any small motor and a gearbox. A 15 volt 385 geared down 1:3 and run on the 7.2 volts suggested should handle the prop just fine and give a controllable amount of power. You are used to vipers - one of them should provide the wanted control without any hassle.