Newbie needs help to size shaft and prop

[Michel Paquette]

Hi there
I want to build a 6'-0 long scale model of a cruser. It is a semi displacement hull nd my model should weght about 66 lbs.
From inquirires made to date, I know I shoud be using twin 12V 700 or 800 motors. Since I want single prop, I will also be using gear box. If I go true to scale on prop, I would be looking at a 3" to 3 1/2" prop.
I have been searching hobby shops on line and found props s in this range, but some have 1/4" shaft and others have 3/16" shaft. The thing is, most place only lists up to 3/16" shaft.
Since I am going elctric and not looking for high speeds, would 3/16 " shaft be good?
I am also looking at posibly a 2 1/2" 3 of 4 blade prop. Woulds this size push my boat"

I would appeciate any hlp you can give me.

Michel

[ReddyWatts]

WOW, it weighs over 10lbs per foot? Are you sure it floats? just kidding!

I would buy a trolling motor and use the motor and controller out of it. You can use a servo to operate the controller. It will turn a large prop with 30lbs of thrust on 12 volts and 30 amps. You could parallel up some NiMH or Lipo battery packs and get nearly 20 minutes of running out of it.

http://cgi.ebay.com/ebaymotors/Minn-...spagenameZWDVW