How to Create a Tight Corner Seam With Laminate

Clamp the two precut laminate sheets to the cutting table, in the L-shaped direction in which you will affix them to the cabinet top. Align the laminate sheets on the cutting table so their overlapping outer corners meet at the same point.

Cut a piece of scrap plywood into a triangle to form a cutting guide that will ensure a tight corner seam.

Butt the overlapping inner edges of the two boards against the plywood triangle. Ensure each laminate board is securely clamped.

Place a straightedge diagonally over the overlapping laminate sheets, aligned from their outer corners to their inner corners. Hold the straightedge in place while you draw a line over the overlapping laminate sheet.

Remove the straightedge and place it on the overlapping sheet, parallel to the diagonal line, and clamp it to the table. Cut the laminate sheets along the marked line, using a trim router and laminate cutting bit. Grasp the router firmly in your hand as you cut the board in a single pass.

Lay the straightedge on the L-shaped cabinet and draw a diagonal line, from the inner corner to the outer corner. Apply a thin coat of contact cement to the cabinet top.

Lay wooden dowels every 15 inches along the top of the cabinet. These dowels help you align the laminate sheets before they adhere to the cement.

Align the mitered edge of one of the laminate sheets against the diagonal line along the top of the cabinet, so they line up. Press the edge of the laminate in place, from the outer corner to the inner corner. Remove the wooden dowels as you hand press the sheet along the diagonal line.

Lay the second laminate sheet on the dowels, ensuring its mitered edge lines up against the diagonal line. Butt the mitered edge tight against the edge of the adjacent sheet, so they form a tight corner seam. Remove the dowels as you press the sheet into the cement.