Model Boat Mayhem

Mess Deck: General Section => Model Boating => Topic started by: freelancer on May 20, 2006, 03:53:22 pm

Title: which motor, prop combination ?
Post by: freelancer on May 20, 2006, 03:53:22 pm

Greetings to all modellers

I am building a 51 inch frigate and ask that all modellers with experience building this scale ( 1/96 ) advise me on which motor / prop / battery combination will likely result in the most realistic speed. I would prefer to install a system which will provide more power than required just to make sure it will reach realistic speeds. I will only install a single shaft, single motor,

I am looking for a battery, motor combination that will provide 30-40 minutes of running time. I anticipate the sailing weight to be less than 10 lbs.

TIA

Title: Re: which motor, prop combination ?
Post by: Shipmate60 on May 20, 2006, 07:01:21 pm

A 550 motor and a G. Sitek scale prop, or prop-shop prop, simon will tell you the best one.
2 x 7.2 0r 8.4 volt 3300 Metal Nickel Hydride batteries or a couple of 2400 Nicads.
The motor should pull about 5 - 6 amps in usual running, but higher when manouvering.

You could also run a 777 motor from Model Motors Direct

Bob

Title: Re: which motor, prop combination ?
Post by: Martin (Admin) on May 20, 2006, 09:24:44 pm

Anyone know anything about or used the "777" motors?

Mayhem

Title: Re: which motor, prop combination ?
Post by: Pirate on May 21, 2006, 07:56:07 am

Hi, my younger son uses a 777 direct onto a 50mm prop shop prop through a kort nossel on his 27 inch tug, it has more!!!!than enough speed, runs cool from 12volt supply for about 1 and half hours. Will say that not all speed controlers like 7 pole motors and lower performance can be a bit iffy if not dangerous to the esc , do be carefull. Another of our club members runs a large 4o inch fishing vessel via 777 on 6 volts at a very good endurance rate and scale speed. I'm sure a word with Allistair will sort things out with you. Oh the other point is the 777 has a very short stub shaft with a brass spline affixed with a grub screw.not a problem just a solution to find!!!
Pirate

Title: Re: which motor, prop combination ?
Post by: Model Boats Website on May 21, 2006, 09:20:49 am

Quote

Anyone know anything about or used the "777" motors?

I did purchase a 777 motor however I found them to be very heavy and it seemed to be slower than the 540 motor I had in previously.

If your after more speed, I would recommend the Graupner motors. ;)

Title: Re: which motor, prop combination ?
Post by: freelancer on May 21, 2006, 03:00:59 pm

Greetings fellow modellers

Thank you for the advice, will certainly look into some of the options mentioned. There seems to be endless variations available however I am now of the opinion the ESC is a critical part of the system, some work better than others-expensice research however LOL

I like the idea of a heavy torque motor rather than high RPM as I wish to have a long cruise rather than a fast one. First time I have heard of the 777 motor, may be worth some study.

Thanks to all for the replies.

Cheers from my dockyard

John

Title: Re: which motor, prop combination ?
Post by: Shipmate60 on May 21, 2006, 04:45:04 pm

If you go for a slower, more torquey motor you will have to up the size of your prop to compensate.
I have used a 4 blade prop-shop prop on a motor giving about 5000 rpm on a 5 foot Battle class, she did go ok.

Bob