Building Plans for Octagonal Picnic Table

Preparing to Build

• To build an octagonal picnic table, you'll first need to purchase 10 boards of 10-foot long, 2-inch thick, 4-inch wide lumber and 10 boards of 10-foot long, 2-inch thick, 6-inch wide lumber. Any kind of hardwood will serve, but make sure it's rated for exterior use.

  Cut eight copies of each of the following lengths out of the 2-by-6 lumber: 38 3/8 inches, 33 3/8 inches, 25 inches, 20 inches, 15 inches, 10 inches, and 5 inches. You should have 56 pieces when you're finished.

  Cut the 2-by-4 lumber to the following measurements: one at 99 inches, two at 48 1/2 inches each, four at 48 1/8 inches each, one at 64 inches, two at 31 inches each, four at 30 5/8 inches each, and eight at 32 1/4 inches each.

Building the Table

• Mark a 22.5-degree angle on the ends of the 2-by-6 boards. Cut on your mark so the ends of the boards are slanted at this angle. Mark and cut a 30-degree angle on both ends of the 99-inch 2-by-4, one end of the of the 48-1/2-inch boards, one end of the 48-1/8-inch boards, one end of the 31-inch pieces, and one end of the 30-5/8-inch pieces. Mark and cut a 30-degree angle on both sides of the 32-1/4-inch pieces, but alternate the angles so they slant different directions.

  Mark and cut a 45-degree angle on the top edge of the already angled ends of the 48-1/8-inch pieces and the 30-5/8-inch pieces. Cut on your marks so the ends of the boards come to a point.

  Lay the four 48-1/8-inch pieces on flat ground in a cross shape, with the 48-1/2-inch pieces lying end to end on one diagonal and the 99-inch piece on the other diagonal across the other six pieces, making sure the slanted edge is pointed down. Nail three metal galvanized strap panels onto the boards: two in a cross going the same direction as the 48-1/8-inch pieces and one on a diagonal over the 48-1/2-inch pieces. Use 4-inch galvanized flathead nails to do this. This is the frame for the seat.
  Repeat the above procedure with the four 30-5/8-inch pieces, the two 31-inch pieces, and the 64-inch piece. This is the table frame.

  Nail 40 pieces of 2-by-6 lumber to the table frame, starting at the widest edge with the 25-inch lumber and working your way in to the center of the table. Ensure the slanted edges of the boards are flush before you nail the next one in, and ensure the boards join on a piece of the frame. Nail the remaining 16 pieces (eight 38-3/8-inch pieces and eight 33-3/8-inch pieces) onto the seat frame, affixing the longer pieces first and ensuring each slanted edge is flush and on a piece of the frame before nailing it in.

  Flip the table frame and seat frame upside down. Place spacers or blocks in between until the seat frame is six inches above the table frame. Lay the 32-1/4-inch pieces on the frames so one angle is flush against the underside of the table and there is 17 inches from the far edge of the seat to the board. These are the table legs. Drill 3/8-inch pilot holes through both the legs and the frames. Bolt the legs to the frames with carriage bolts that are 4-1/2-inches long and have a 3/8-inch diameter. Sand the table and seat down, and then stain or paint it to finish.