Servo Possibilities

As my TP52 progresses (slowly), I got to thinking. Would it be possible to splice two drum winches together so that they operate off of the same channel but perform different functions? As I try and design a system that will allow and overlapping jib, while continuing to keep the control lines below deck. I think if this were possible it would be quite doable. Using (2) drum winches, one for the main and one for the jib, but when the trim stick is moved, they move simultaneously. Obviously a lot of math will be needed to also ensure that the sails move simultaneously too, but thats the least of my worries. Thanks for any help or opinions.

I think one of the newer radios with channel mixing, you would have single stick operation with trim and end points on both servos

This is possible and actually not that difficult, although the way I originally did it there were some limitations. I did the original setup using an arm servo rather than a winch and it worked ok as well. All from a standerd two channel set.

Heres how it worked.

Initially, completely ignore the mainsail and focus on the genoa setup. i used a system where by if the stick was right up, the genoa was to stbd and if it was right down the genoa was to port. It was simply a closed loop system, running fwd under the deck, with two take off points, one each side of the turning block in the loop. When one point was near the drum, the other was near the turning block in the loop and vise versa. Both sheet exit points were near the drum. This allowed control of the genoa.

Now on top of that drum was another drum and closed loop system which ran aft. There was a single take of point which travelled the length of the loop as per normal but rather than having the exit point for the sheet at one end of the loop, it was half way along. This means that when the stick was right up, the mains was sheeted right in, when the stick was in the middle the main was right out and when the stick was at the bottom the main was right in again. See where this is going?

As the boat tacked the genoa travelled from side to side and the mainsail went from being sheeted fully in to fully out and then to fully in again. To sail downwing the stick was in the middle, the main was right out and the genoa would be trimmed on centreline. It still filled and set ok, not brilliantly but ok. Like i said there were some limitations. But it did allow a genoa setup to work on a 2 channel set.

As time went by I got a four channel set and almost every boat I’ve buit since has used a genoa.

Heres a link to one of the later ones

Hope this all makes sense.


Very nice video. Thanks for the input, I don’t know exactly what type of radio set up I will have yet, but at least I know there are several viable options.