To build a balance beam, first cut the 2×4’s into 4′ pieces (6 pieces in all). With 4 of these pieces, use a skill saw, miter saw and/or table saw to cut a 2”x2” notch in one end to create hinge. With the remaining 2 pieces, cut a notch in both ends.
Pair the 6 pieces into 3 matching pieces. Glue, firmly clamp and allow to fully dry. When dry, secure with two wood screws in each piece, pre-drilling the holes to prevent splintering. Sand the notched ends until they are even and smooth. Use a miter saw to round the notched ends and sand.
Place the pieces together to form the beam. Drill a hole slightly larger than the 3/8” bolt through both parts of the hinge area.
Using the 2” thick board, trace 6 semi-circular “feet” with a 6” radius. Cut out with a band saw and sand until smooth. Using the 1”x4” board, cut 6 pieces ( the “foot-base”) 14” long. Sand.
Measure the beam and cut a corresponding notch 2.5” deep in each semi-circular “foot”. Trim and/or sand as needed until the “foot” easily slips over the beam. Glue the 1”x4” foot-base to each foot and allow to dry. Pre-drill holes and fasten foot-bases to feet with 2 wood screws each.
Assemble all pieces, attaching feet to beam and fastening hinges with bolts, placing a washer on top of the beam, between the two parts of the beam and above the nut. Trace the head of the bolt with a pencil, then remove bolts and route around the marks with a router to counter- sink bolt. Replace bolt. Test hinge for smooth operation and feet for solid foundation, trim or sand as needed. Sand or route all edges, including all edges of feet and beam.
Take pieces apart. Apply wood filler to seams between 2×4 pieces (any anywhere else as needed). Allow to dry, then sand. Paint all pieces with primer and at least 2 coats of non-toxic acrylic paint, sanding between coats. Allow to dry, then re-assemble. Apply non-slip tape to beam.