Now I am building this 4 feet Mistral Motor Yacht , which is having twin propeller.
If anybody having an idea to make it R/C please advice.

Thanking you.
SB Maharana

SB Maharana,
 
Welcome to RC India.... Regarding your query, VC is very knowledgeable about RC boats...You can contact him via http://www.rcindia.org/profile/?u=361 . He recently built one... please see his threat at www.rcindia.org/boats-kites-trains-and-all-others/cabin-cruiser-naughty-cal-antares

Good luck.

"VC is very knowledgeable about RC boats"

Sethji my friend, thanks for the compliment, but after seeing the fantastic quality of Mr. Maharana's builds, I can't help but laughing hysterically at this statement! I have a lot to learn from Mr. Maharana.

I had a long conversation with SB (Mr.Maharana) today. SB needs some help about wiring the 2 motors (brushed) to the Tx. What ESC's can be used on this set up? The props are contra rotating and he would prefer differential control on the motors. I presume he will be using a 3 Ch Tx / Rx.

Let the real experts take over from here.

Cheers!

VC

Here I made a little effort to make a low budget RC for model boats.

Hi Maharana,
This is simply superb. I really liked the way the rudders are controlled. I am sure with this can be operated even with a toy remote. Kindly let us know how have you slowed down the rudder motor. Also let us know how were the props built.

Shreekant.

Rooster,
if u want to slow down a motor for rudder, like in this video u need to use gear system for motor.
and best ways is using servo!!!!
yes i think u can use servo, take servo open it up, remove the circuit and feedback potentiometer and it will operate as simple motor with gear system, means u have slowed the speed of motor tot control ur rudder!!!!
but to control motion, clockwise/ anticlockwise, u need some different mechanism!!!

+1.  Would like to know more about the rudder motor setup !

Creativity at its best! Love to see more ingenious stuff like these.. 

I have used gear motor to control the rudder ( 10 rpm), Gear motors are very powerfull due to large reduction rpm from the driving shaft and are very cheap compared to Servo.

You need a DPDT (Double Pole double through) Switch to change the rotation of any dc motor, actually the switch changes the polarity of motor which in turn change the direction of motor. 

Pure Genius! Maharana is an asset to this community. I am so glad that I suggested him to join us. If I've done one good thing for RCIndia, that is getting this gentleman on this forum.

Actually I was waiting for your reply !!!

Maharana my friend, I don't possess a fraction of your knowledge or expertise. My comments are of no consequence. I am learning from you. Keep up the GREAT work, teaching and inspiring us.

God bless!

So the reduction gears are inside the motor case itself ?  It is common to use reduction gears outside the motor, but this is something different and new (at least for me). Can you point to an online reference of the same ?  Or do you pick them up from local stores ?

I think he is using planetary gearboxes. They provide excellent thrust and the output shaft will be inline with the motor shaft. They are available from WWW. BPHOBBIES.COM .
Here is the link  http://www.bphobbies.com/view.asp?id=V836600

The problem is they don't ship to countries other than U.S.A. and Canada. I have one gearbox for speed 600 size brushed motors which I use in my SPECTRA Electric Sailplane. I got it from a friend who lives in U.S.A.

Rao Garu, the Administrator gets angry  when you quote US/Foreign Sites without doing your research about Indian sites first. We shouldn't look "far and wide" before we check what is available in India. So here it is, Maharana Sir probably uses a lot of stuff from here. I've also bought from this site, they are very reliable:

http://robokits.co.in/shop/index.php?main_page=index&cPath=2

Anwar Sahab, Peace!

Actually I purchase everything in local stores, they usually dont sell these type of products but when i explain them about my requirement they get things from Raipur.

Online store - http://robosoftsystems.co.in/roboshop,
I am in touch with this company to have RC systems, but not purchased anything.

Guilty as charged  

Rao Garu,
Low RPM motors/ Stepper motors are available in every Robotic store in INDIA.
10, 30, 60, 100, 300 rpm gear motors costs around Rs. 150~180
There is a new motor 100 rpm (High torque) is a excellent prouduct, where they have used 25,000 rpm as the drive motor costs around rs. 1000/-

Shaping up - Mistral

ship fittings & life boat

Maharana,
Awaiting your post on making props from scratch.

Shreekant

Don’t worry I will make it soon.

I was little busy last month, no much progress in completing Mistral boat, but learned the art of sculpting with M-Seal, and made some figures to suit Mistral boat.