Drive System Questions

[redboat219]

I have a couple of questions regarding drive systems;

1. In boats with twin screw drive, what are the advantages/disadvantages of using a single motor to power 2 screws compared to using 1 motor to drive each screw?

2. What are the advantages/disadvantages of using a direct drive compared to a drive with reduction gearing in the above mentioned set-ups?

[Massey]

I will do my best to answer this for ya.

1 The advantage of one motor to 2 screws is that you will only need one ESC and the wiring is simplified. Disadvantage would be the gearbox, they are usually but not always noisy and require maintenance.
2 motors 2 screws advantage is you have more realistic control of your ship if you use 2 ESCs and 2 channels, but that brings the disadvantage of more complicated wiring and the need for 3 or more channels.
I personally prefer to have the control so I would go for the 2 motor 2 screw method. Plus if the motors are on seperate channels you can use that as a backup stearing if something goes wrong with your rudder.

Now for your second question.
direct drive is good for go fast boats that will have a free turning prop (IE Surface drive) where the RPM is your primary concern, Good for small light boats that do not need the torque from the gear drive, It is alot simpler to use and is also great when space is a main issue.
The disadvantage of this is larger motors are needed to preform the same amount of work. They can consume more battery. I may be missing a few points here but I am sure others can fill you in on other disadvantages.

Good points of gear drive are, More torque is gained so you can use smaller motors to push around larger heavier ships. Great for towing and applications were speed is not needed. Generally but not always increases run time because the motor will draw less amps.
The only real disadvantages here are, more room is needed in the hull, and they do require some maintenance to keep them in good running order. I think that the belt drive is the way to go, they dont need oil and the maintenance is alot lower than with gear drives.

Now in a tight space you can still use a gear drive but you will spend a little more money for the Inline or Planitary type reduction boxes so, if you do need a reduction box and are tight for space you may be in luck.

Massey

[IWC]

what would be a good beginner boat utilizing a twin screw set-up two motors.

[Massey]

what would be a good beginner boat utilizing a twin screw set-up two motors.


Soon there will be a Vac-U-Tow2 available at www.vac-u-boat.com it is a towboat with twin screws, and knowing any kit available from Phil the boat will be easy to build with good instructions and can be customized to look scale as well. Check them out.
For other types of twin screw boats Im not sure what is out there but I would imagine you could find a PT boat or something like that.

Massey