Building an octagon picnic table can be a very challenging task. With this guide, however, you’ll be able to build one for yourself.
Step 1- Cutting the lumber
Using your 2X6’s cut eight of each of the following measurements. 38 3/8”, 33 3/8”, 25”, 20”, 15”, 10” and 5”, they should equal out to 56 pieces total. Now, cut the 2X4’s at the following measurements. One 99” board, two 48 1/2” boards, four 48 1/8” boards, one 64” board, two 31” boards, four 30 5/8” boards and finally cut eight 32 ¼” boards.
Step 2- Fine Tuning the Cuts
Take all your 2X6 boards and mark a 22.5 degree angle on the ends of them. Cut along the angles so that all of these boards are slanted at a 22.5 degree angle. Cut a 30 degree angle on both sides of your 99” 2X4, on one end of your 48 1/2” boards, one end of the 48 1/8” boards, one end of the 31” boards and finally on one end of the 30 5/8” boards. Make a 30 degree angle on both sides of your 32 1/4” boards, alternating the angles so they slant in different directions. Cut a 45 degree angle on the top edge of the angled sides of your 48 1/8” boards and the 30 5/8” boards so they come to points.
Step 3- Assembling the seat frame
Lay out the four 48 1/8” boards on the ground in a cross pattern with the 48 1/2” boards lying end to end on one diagonal. Put the 99” piece on the other diagonal across your other six boards; make sure your slant edges are pointing down. Using your galvanized flathead nails, nail three of your galvanized straps onto the boards, two following the directions of the 48 1/8” boards and one over the 48 1/2" boards.
Step 4- Assembling the table frame
Do exactly what you did in step three but use your four 30 5/8” boards, your two 31” boards and lastly, your 64” board. Your table frame is now assembled.
Step 5- Putting it together
Next you’ll need to nail forty pieces of 2X6 to the table frame starting with the 25” board working your way inward and using the board that’s the next size down as you go along. Make sure the slanted sides of your boards are flush before nailing in the next piece. Nail in the eight 38 2/8” boards and the 33 3/8” boards onto the seat frame. Do the longer boards first and make sure all edges are situated correctly on the frame before you nail them down. Flip the table and seat frames over, placing spacers in between the two until the seat frame is six inches higher than the table frame. Put the 31 1/4" boards on the frames, making one angle flush against the underside of your table and leaving 17” from the far edge of the seat to your board. These will be your legs so drill 3/8” pilot holes through both legs and the frames. Bolt your legs to both frames with your galvanized carriage bolts.
Step 6- Finishing Touches
Sand your table and stain or paint it to your heart’s content!