It may be your turn to host your entire family for a large holiday dinner and your dining table currently seats four people. You may have a leaf that will extend the table to six, but you may want to double -- or triple -- your seating. One way to temporarily oversized your table is by using a custom table extension. This is a table top that rests on top of your existing table with or without a second set of table legs. It has a nice wood appearance. A second way is to make a table top that is 8 to 10 inches larger than your existing top and mount it to your table from the underside. This is a more permanent solution for a small or damaged table top.
Measure the dimensions of your table top. Cut felt to these dimensions with scissors. Place the felt on the table top to protect the surface.
Measure from the height of the table top to the floor. Purchase a table top extension pad for your table height. The pad can extend your table by 8 to 24 inches on each side.
Assemble the pad sections (they go together with attached Velcro tapes). Screw the legs into the wooden splines. Place the pad over your table making sure the secondary legs are straight. Adjust the table height by screwing the adjustable feet.
Cut 1x 10 inch cabinet grade wood to length. Line the top of the boards up against a stop top side down. Use a straight edge and draw horizontal lines 2 inches from the top and bottom edge across where the boards touch each other and every 10-inches between. These are the marks for your biscuit joints.
Cut biscuit joints at each mark. Add a bead of carpenter's glue between the edges of each board and at each biscuit. Bring the boards together and clamp them with long wood clamps until the glue is dry. Wipe off any excess glue.
Measure and cut 1 by 3-inch wood of the same grade and type to fit around the bottom perimeter of the table top. Glue and screw the smaller boards to the table top from the bottom. Wipe off excess glue. No screws should come through the table surface. After the glue dries sand the table top and sides with an orbital sander until the surfaces are smooth.
Route the top edge of the table with a router and finish sanding. Place the new top face down on the floor. Cut felt the size of the old table top and centre it on the underside of the new top. Invert the old table and centre it on the new top. Place metal mounting brackets (flat z shape), two on each side of the table, and screw the tables together using wood screws.
Turn your table right side up and finish using the stain or paints of your choice.
Adding the trim boards to the underside will give the table a stronger profile and further hide the old table top.