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Michel Paquette
02-18-2008, 02:37 PM
I am looking at building a scaled model af a 50' cruiser type boat.

The actual boat is a 50' semie displacement hull, pleasure cruiser. Displacement (weigth) is 33,000 lbs and cruising speed is 13 knots.

I wish to build it at about 1/8 scale, making it about 6' lg and having a weight of about 70 lbs.
This will be my first electric powered boat and I need to know what size of motor I need for this model.
If I keep to the scale, I will need a 3.75" Dia propeller.

Michel Paquette

SJFE
02-18-2008, 03:01 PM
I would go with duel motors. Either brushed 800 or 970's. 2 jeti 600 or rchydros 90 amp esc's should be fine. You can run twin drives or mount both motors on a gear box for a single drive option. A brushless set up of equal power will cost you 3 times more.

ReddyWatts
02-18-2008, 05:12 PM
I think Johnson/Evinrude makes a motor for it. ooops that's gas. j/k

Flying Scotsman
02-18-2008, 05:37 PM
Ah, scale boats my first love, review Mack Marine for motor and other bits and pieces. Also you want to use ESC's such as MCD as they offer total control over the full rev range and no magic smoke!!!
Douggie

Michel Paquette
02-21-2008, 08:16 AM
Thank you for the info. All I need now is the best place to buy all this stuff. I have lookes at Offshore Electric, and they don't seem to have these motor size,
Gear box or a 3.75" prop that I am looking for.
I have also looked at Mac's marine which has the gear box, but I still can't find the prop size that I want. Also they seem to have such A variqty, how do I find the right one I need?
The information given up to now is a start but I need a bit more technical info, like how much torque do I need, and how mucch torque do these motors put out?
I might be asking a lot, but I don't want this to be a trial and error sizing.