by Peter Jackson, photos by Peter Jackson
Footys are pretty small boats, so it can be difficult to mount internal electronics inside the hull. Roger Stollery, though, came up with an ingenious way to avoid the problem. The idea is to mount all the operating controls on a removable hatch cover. Not only is the cassette convenient for accessing the electronics, it also makes it easy to have a spare cassette, which is easily fitted as a replacement if problems arise during racing
see Figure 1).
01-Cassette-0125.jpg. Figure 1: Cassettes are interchangeable. Peter Jackson photo.
t took me a long time to adopt the system of cassette housing of the electronics on a racing yacht. The main problem in my mind was the lack of waterproofing of the servos; however, using the system developed by Roger, this has proved unfounded.
Using the cassette concept, servos are mounted from underneath the hatch cover (cassette plate) and poke through the plate. One
servo arm then connects to a rudder arm, and the other connects to the Stollery power arm (Figure 2 and 3).
02-Cassette-0118.jpg. and 03-Cassette-0119.jpg. Figures 2 and 3:Topside and below deck; a completed cassette. Peter Jackson photo.
The power arm is a unique feature, which allows the use of a nine-gram servo for sail control. There’s not much torque in a nine-gram servo, but the power arm makes the best use of it. The wire power arm is curved so that the sail-control sheet will move freely along the arm as the servo sheets in and out. At the power arm’s most forward position, the sheet is fully out for downwind work, and the end of the sheet (fastened to a clip or ring) moves to the outer end of the arm. When sheeted in on a beat, the arm points to the side of the boat, and the sheet moves in to the servo end of the arm. The movement of the sheet to the inner end reduces stress on the servo, thus permitting a micro servo to do a big job. An additional nine-gram servo is used for rudder control (Figure 4).
04-Cassette-0121.jpg. Figure 4: Power arm and rudder control. Peter Jackson photo.
The servos are attached to the bottom of the plate by means of hot melt glue, which is placed all round the servo, thus creating a waterproof joint. It is also a good idea to insert the
receiver in a balloon, with an elastic band to close the balloon mouth. To further waterproof the servos, a small “O” ring is placed over the output spline; then a foam ring, impregnated with silicon spray grease, is placed between the servo arm and the “O” ring (Figure 5).
05-Cassette-0123.jpg. Figure 5: Waterproofing the servos. Peter Jackson photo.
The cassette is fixed to the deck with black electrical tape. Some brands seem to stick better than others, so be sure to test the adhesion before you venture out on the pond (Figure 6).
06-Cassette-0120.jpg. Figure 6: The cassette taped on deck. Peter Jackson photo.
Meet the author
eter Jackson is a retired Chartered Engineer of the Aeronautical type, and he has built model aircraft since he was eight years old. He came to sailing about six years ago and started to design and race Footys. He has branched out to larger-boat classes in the UK, but his primary passion is with these little Footys, which take an inordinate amount of skill to sail well. With his good friend Peter Shepherd, Jackson organizes and runs a model boat club and attends all of the open Footy Events in the UK.
06-pj picture.jpg. Author photo: Peter Jackson.