Chinese Junk Boat

below a picture of the junk boat. I decided for a junk, since I read that they are really easy to handle. I built the boat from strips of beech wood. I bated the boat and painted several layers of G4 finish on it.

Below the servos and the winch for the sail. Since winches are too expensive for me, I have built one out of a servo. I have filed out the block from the gear and soldered out the potentiometer. Then I soldered in a trim potentiometer. I took an old screwdriver and cut off the tip. I glued the screwdrivers tip on to the axis of the servo disk. With strip of wood I fixed the potentiometer trimmer and the servo. By doing all this, I can get 4 revolutions, which is enough to control the sail. This method is also described here. I noticed that the rope is sometimes tangled up, if the sail is not pulling it. Therefor I need to build in a mechanism to tighten the rope. I have built a open box with two holes for the rope. Within this box I threaded the rope into several washers. The weight of the washers tightens then the rope.

In general junks dont have fins (maybe fins on the side). I decided to build in a fin to stabilize the boat further. Before that I put in many weights into the boat but this caused too much draft. Below the boat swimming in a lake.