Use this simple design and two-by-six treated lumber to construct a picnic table with built-in benches. Set up an assembly line and end stops to cut multiple pieces of identical dimensions. Screw the components together initially, but insert carriage bolts to hold them securely for the strength and stability to serve an immoveable feast and seat many people!
Measure and mark for angle cuts on the ends of the two-by-six planks as you construct the end frames for the picnic table. Use a bevel gauge to transfer the angle to the power miter saw.
Set up the power miter box with end stops to ensure that like picnic table components are cut exactly to length. Using an assembly line to cut multiple pieces makes the project go faster.
Use a workbench to position a short and a long lateral support (for the picnic table top and benches, respectively) onto a pair of angular legs. The resulting end frame resembles an uppercase letter "A." You'll need two per table.
Pre-drill and initially attach the end frame components for the picnic table. Next, drill additional larger holes through all the thicknesses of the end frames for the carriage bolts.
Insert carriage bolts through the large holes with the smooth heads inside to protect legs from getting scratched under the picnic table. Add washers and nuts on the outside, finger tightening them and snugging them with a socket wrench.
Set the end frames upright and evenly position the planks for the picnic table top, spacing them 1/4 inch apart with temporary spacers. Pre-drill holes and drive in screws to secure the planks to the supports.
Position outer planks for the picnic table benches with an even overhang at the tips of the supports and centered on the table. Space the second bench blank 1/4 inch away and secure all to the supports with screws.
Add cross braces to the underside of the picnic table top, spanning laterally across the planks. Secure angle braces from the table top to the end frames for even more stability and strength.
Brush on multi-surface sealer to penetrate the wood to seal and waterproof the picnic table and protect it against sun and weather. Let it dry thoroughly per manufacturer's directions before using the picnic table.