Find the joists in the ceilings with a stud finder. You must attach the chin-up bar to the studs to secure the homemade bar safely and properly. Use a pencil to mark the ceiling where the joists are.
Attach a 90-degree 3/4-inch diameter elbow on the end of a threaded 3/4-inch diameter metal pipe with a pipe wrench. Use a threaded metal pipe that measures 40 inches long. Attach the second 90-degree 3/4-inch diameter elbow on the other end of the threaded 3/4-inch diameter metal pipe.
Screw an 8-inch long, 3/4-inch diameter threaded pipe into the open end of the elbow with a pipe wrench. Attach the second 8-inch long, 3/4-inch diameter threaded pipe into the open end of the other elbow. Place a flange on each end of the metal pipes.
Place the assembled bar on a piece of 2-by-6 board and mark the areas with a pencil or pen where you will screw the flanges into the wood.
Secure the 2-by-6 board to the ceiling with 3-inch wood screws, making sure the board is screwed into the joists for proper support.
Line the flange holes up with the marks you created in Step 4. Mount the chin-up bar to the 2-by-6 board by screwing 2 1/2-inch wood screws through the flange holes and into the board.