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[zebec63]

Hi all, prob not the right place to ask this but as I'm a newbie !!!
I am about to start construction of my first ship, A french sloop, 3 masts, square rigged, partly kit built, part scratch build. 1/48 scale so not too big. About a metre long.
I am looking for a sail winch that only moves when the Tx stick is off the centre point. Basicaly when the Tx stick is centred the winch stays put, either in or out.
Does anyone know of a commercialy made unit or am I going to have to scratch build one ?

Thanks   Shaun

[dougal99]

Hi there Shaun

Welcome to the forum. You can achieve what you want by using a ratchet on the TX stick, so that it remains where you leave it, thus the winch stays where it was left.

HTH

Doug

[zebec63]

Thanks for the reply,

I had considered using the ratchet but I am hoping to use three separate winches, one for the foremast, one for the main and mizzen (linked) and one for the driver. Each on it's own channel and a std servo for the rudder.
Main reason for this type of winch is to try and keep the sailing simple.
Any other advice would be welcome

Thanks  Shaun

[Tug-Kenny RIP]

I have a Futaba Skysport 6 on which there is a channel controlled by a Knob. This would stay in the position which was selected. I use it to control a servo with switches on, so maybe this would be ideal for you ?

Cheers...Ken

[zebec63]

Hi,
Think I've got the solution. Bought a std Hitec servo, opened it up, cut off the stop that limits the rotation, cut off the tang that connects the pot and glued it at the neutral position, put it all back together.  Problem solved. only rotates when you move the stick off neutral. Small, light, simple and cheap !!

[malcolmfrary]

Thats much the same solution that I have used these last mmmmpphhhmm years.  The dead band is very narrow, so you might (will) get some creep.  The easy way is to re-mount the pot outside the unit so that yo can do the fine tuning when required.  Much easier than stripping the servo.
An alternative is to look for robotics websites where they detail modifications to servos to increase the deadband.
If possible, have the winch drum work a continuous loop, and fix a take-off where convenient.  A single-ended line to a drum is usually a recipe for disaster when paying out if any slack is allowed. 

[zebec63]

Hi,
The plan at the moment is, for instance, the foremast. Take a lead ( rope, sheet, haliard,) from one end of the yard, run it back to the main mast, to a pully or block, then down to the deck, turn it through 90', forward to a windlass or capstan, two turns around it, then back the same way to the other end of the yard.
I built a test rig to try it and work out the best positions. It worked ok but still needs fine tuning. Planning to have the servos under the deck connected to the capstans. Then all the ropework is above deck so hopefully easy to fix.
The main problem at the moment is keeping the lead tight enough to stop it slipping on the capstan but that might be the cotton thread I have been using.
Having fun at the moment trying to work out how to build a split hull like HMS Leopard, page 42 in Martin Becker's book

Thanks  Shaun

[malcolmfrary]

The plot sounds OK, but remember that the total length might not remain constant, so the string (tech term) needs a springy bit (another tech term) on the "take up" end, which is the end with the least pull on it in this case.  I get away with an elastic band.  This does need changing from time to time, so access is a must.