How to Make an Angled Mounting Block for Table Legs

Flip the table upside down.

Position the flat bottom of the protractor against the horizontal table bottom and determine the angle of the surface where you'll be placing the mounting blocks. Put the center of the protractor at the edge of the surface to measure the angle.

Subtract the angle measurement from 90 degrees to determine the angle for the mounting block. If there is a 30-degree measurement from the table bottom, the mounting block surface will need to have a 60-degree angle.

Put a 3-inch wood cube on a flat surface and stand the protractor beside the block, with the center of the protractor at the edge of the block. Use a pencil to make a mark at the same angle that was found on the table bottom in Step 2. If the table bottom had a 30-degree angle, mark the wood at the 30-degree point. Draw a second mark on the corner of the block that aligns with the bottom center point of the protractor.

Draw a line across the wood cube. The line must run from the corner mark through the 30-degree angle mark. The wood below the line will be cut away, leaving a block with a surface that sits at a 60-degree angle.

Wear a face mask and protective eyewear.

Cut the wood block, using the line as a guide. A number of saw types are suitable for this project, including table saws, hand saws and circular saws. Discard the portion of block that fell below the line. One side of the block will sit a 60-degree angle.

Attach the mounting block to the bottom of the table. The 60-degree angle will sit against the 30-degree angle, resulting in a perfectly horizontal surface where you'll mount the table leg. The precise method for attaching the mounting block varies, according to the table design. Use wood glue in cases when a screw would penetrate the table top or skirt.