The wind vane on a sailboat serves the same purpose as a tell-tale: it indicates wind direction. While the tell-tale is little more than a strip of ribbon attached to a stay, the wind vane is a more substantial and attached to the mast.The wind vane's mounting may also serve as a mount for a variety of other weather instrument sensors, such a temperature, wind speed, barometric pressure and even a radio mast, as well as holding the simple wind direction indicator.
Cut a right triangle out of the thin aluminum plate with metal shears. The triangle should be large enough so that, when mounted at the top of the mast, it can be readily seen from the deck. The hypotenuse of the triangle is the top.
The caster bearing should be soldered to bottom of the aluminum triangle 1/3 the distance from the tip, with the shortest side (the rear of the vane) vertical. This allows the rear of the wind vane to drive the tip of the wind vane to show the direction in which the wind is blowing. Use Zinc/Aluminum solder, 85Zn/15A or comparable. Remember that, when soldering aluminum, using flux will prevent the formation of aluminum oxide. Aluminum oxide will prevent a good solder joint from forming.
Cut the aluminum tubing with the hacksaw, to a length 4 inches longer than the bottom of the aluminum triangle. Use the tubing bender to bend the tubing 90 degrees, 5 inches from one end. Insert the short end of the tubing into the bottom of the caster bearing and solder to the interior ring of the bearing race.
Cut a 1 inch x 2 inch piece from the 3/16 inch aluminum to form the mounting plate. Drill two screw holes through the plate, centered and 1/4 inch from each end. Solder the end of the aluminum tubing without the vane, to the center of the plate, so that the tubing is perpendicular to the mounting plate
