On rare occasions, the pylon in your ski boat can become warped, or may need replacements along with the floor boards. The United States Water Ski Association has strict sizing requirements for ski pylons, and they must be able to withstand extremely heavy loads. It is very important that the pylon be precisely centred in the boat so that it does not give the skier an advantage on one side of the course and must be able to accommodate the rope swinging from side to side.
Measure the height of the engine cover from the water line when there are no people in your boat. Your ski pylon must be between 65cm and 120cm from the waterline, per USAWS specifications and must clear the engine cover. Remove the floorboards and cut the steel pole to length.
Slide the pipe into the mounting base and mark the locations of the mounting holes on the pipe with a marking pencil. Drill holes through the pipe at these locations.
Taper the top of the steel pipe with a grinding tool so that the pole tapers to a diameter of 1 1/2 inches, 3 inches below the top of the pipe. Drill a hole through the side of the pipe 4 inches below the top of the pole with a 3/4-inch drill bit, making sure it is facing side to side when the mounting holes line up with the base. Tough up the rough steel with a medium file, then a fine file.
Slide a 3/4-inch pole through the drilled hole at the top of the pylon and make sure it is centred. Put on your safety goggles, gloves and welding apron and weld the pole to the pylon.
Slide the pylon into the base plate, secure it with mounting screws and replace the floor boards.