Hi Mark,

There are several options when it comes to fitting a sailwinch and to some degree it comes down to personal preference which route to go down. The initial choice is between a sail arm winch or a drum winch

The sail arm solution is usually the simplest, easiest, cheapest and quickest solution. However sometimes it is not possible to find space in the hull, or get a servo with enough torque to pull in a big sail. On a number of smallish yachts, up to about 40 inches long I have used a Hitec HS815BB sail arm system and a typical installation is shown below.

The above yacht is a slightly unusual design in that the jib sheet comes through a fairlead/sheeting nipple in the deck on the LHS and the main sheet comes through a fairlead in a panel which fits on the deck. There are various types of fairlead you can use, have a look at the Nylet or Sails Etc websites to see some examples. In some cases I have made my own using a short length of brass tube glued through the deck to guide the sheet.

The tricky part is working out the position of the sheets relative to the jib and main booms. To make the best use of the available torque you need to attach the sheet as far away from the boom pivot as possible. However you will be constrained by the travel of the servo. The Hitec HS815BB provides 200 mm travel when used with the standard sail arm supplied. It is possible to add extensions to this or the other arms supplied, so that the travel on the jib sheet is shorter than the main sheet, as can be seen in the photo. Its possible to work out the geometry of all this using (simple) trigonometry or you can draw out the installation full size and experiment with different dimensions till you find a solution that fits.

A second option is a drum servo which drives a loop of cord around a pulley. The sheets are attached to this loop (I usually use a bowsie for this). The advantage of the drum system is that you can get much more travel in a longer narrow space inside the hull and potentially more force applied to pull the sail in. I have fitted this type of system in a number of old yachts, without removing the deck, typically working though a hatch about 5 inches square. I always make up the drum and pulley system outside the hull as a sub assembly and then install it complete, as shown in the photos below.

I generally use a Hitec HS785 servo for these applications which give you a travel of about 450 mm with a typical transmitter and receiver. You still have the same problem of working out the geometry of where the sheets should exit the deck to attach to the booms.

For both the above options you can adjust the overall travel of the system and the end points by either using a 'computer' transmitter which provides that capability or by using a Servomorph, available from Component Shop (other options are available).

A third option is to use a drum winch with a 'captive drum' which encloses the cords and may enable you to connect the sheets directly to the drum without using a loop. I have not had any great success with these as sail servos, but I believe others have, however I don't know what they are doing differently to the approach I tried.

You have made a very nice sleek looking hull, a bit like the Nottingham J class ones. Have a look at the build manuals on the Nottingham J class website as it gives you another option of how to install a drum servo loop system. There is a link to the build manuals here **LINK**

I hope the above gives you some ideas. If you have any questions come back and ask.

Gareth