Golf carts come in a variety of different sizes and shapes. An average golf cart will hold two people and have an area in the back for the golf bags. When golfing with more than one other person it can be a hassle if you only have two seats in your golf cart. One way to fix that problem, without buying a new golf cart with four seats, is to add your own custom back seat for a fraction of the price.
Put on safety glasses and cut a piece of 1/2 inch thick plywood for the base of the seat using a circular saw. Cut the board to the same length as the front seat and 1 foot wide.
Cut a piece of 2 inch thick foam to the size of the board using a razor knife.
Spray the entire top side of the ply wood with spray glue and attach the foam to the wood. Let the glue harden for one to two minutes.
Cut a piece of thick vinyl for the seat cover that overlaps the edges of the plywood by 3 inches. Lay the vinyl on the floor with the underside facing up. Lay the plywood covered in foam in the center of the vinyl, with the foam against the vinyl. Fold one side of the vinyl up and staple it to the plywood using a heavy duty stapler. Pull the opposite side of the vinyl tight and staple it in place. Continue this process for the other two sides.
Make the back rest out of plywood and foam following the same process as in Steps 1 through 4. The back rest should be the same size as the back rest in the front seat.
Measure from the back roof support bar down to the bumper. Cut two metal pipes to this length using a right angle grinder with a cutting disc.
Mark the pipes where they will have to bend at a 90 degree angle to go down to the bumper. Light the propane torch and hold it on the mark until the metal is hot enough to bend. Bend the pipes and let them cool. Hold the first pipe next to the second pipe while you are bending it to make sure they have the same angle.
Measure from the left rear roof stabilizer bar to the right one and cut a pipe to this length. This will be the stabilizer bar for the rear seat supports.
Wipe the pipes clean with acetone and a rag and let them dry. Spray paint the pipe with black spray paint and let them dry.
Place the rear seat support bars in place and drill holes with a 1/4 inch drill bit through the roof stabilizer bars and the rear seat support bars. Secure them in place with 1/4 inch bolts.
Measure out 1 foot from the roof stabilizer bars on the rear seat support bars and make a mark with the marker. Drill a 1/4 inch hole directly through the rear seat support bars from top to bottom. Place the stabilizer bar on the holes and match drill them with the 1/4 inch bit. Secure the stabilizer bar with 1/4 inch bolts.
Place the seat on the bars and secure it to the front seat posts using straps. Place the back rest on the back of the front seats back rest and secure it in place with straps.