T-Pain Is On A Boat: Re: [Electric Boats] Illusive gear ratio THE RESULTS ON PAPER

Thursday, April 18, 2013

Re: [Electric Boats] Illusive gear ratio THE RESULTS ON PAPER

Orest:

did u see my email about going to 14" and redo test??

its relative, and if dock is available, will be close. main thing, 15amp controller, 15amp motor fla right??

good luck, gerald b.

--- On Thu, 4/18/13, Orest Iwaszko <orestyko@hotmail.com> wrote:

From: Orest Iwaszko <orestyko@hotmail.com>
Subject: Re: [Electric Boats] Illusive gear ratio THE RESULTS ON PAPER
To: electricboats@yahoogroups.com
Date: Thursday, April 18, 2013, 12:52 AM

Andrew Im blown away by your analytics. My appologies , I was double checking the gear ratio because the tack results came to 4 :1 and sure enough the big pulley is 10 "
Was the fact the boat was tied to the dock during all the tests accounted for ? Humbly Orest

On 2013-04-17, at 7:18 PM, Andrew Gilchrist wrote:

According to the performance graph the maximum amps draw, at full throttle should be 13.6 amps, where the rpm will be 1788 this will output 8.8lbs of torque.

14"pully 5.6:1 is a straight reduction to allow the motor to run at 1788 rpm; however at 14 amps and 14"pully the torque to the prop is only 47lbs whereas in the present setup torque to turn the prop at 275 rpm is 41lb and the torque rpm relationship is liner so maybe 290?

Go for 13.5"first it may be the best compromise and if you can borrow or rent a few options

Yours,

Andrew Gilchrist

fastelectrics.com

Australia

0419 429 201