How To: Installing Custom Square Molding

Steps:

1. Measure the ceiling around the room. The 6x1 poplar will attach directly to the ceiling, and the 3x1 will be attached flush below it.
2. Measure and cut the 6x1 poplar with a table saw to fit in each section of the room. Try to cut out any knots; we want to have a nice clean finish.
3. When you reach the corner pieces, use a miter saw to cut the wood at a 45-degree angle so the pieces fit together.
4. Mark on the back of the wood which section the wood goes in for easier installation.

5. Repeat steps 2-4 with your 3x1 poplar.
6. Using a block plane, take a slight edge off all the corners at 45 degrees (also called arising).
7. Paint the 6x1 and 3x1 sections of poplar on the top and sides and let dry. Leave the underside (with the locations marked) unpainted.
8. Run a strip of carpenter's glue along the unpainted side of the first 6x1 and attach it to the ceiling, making sure it's flush against the wall.

9. Use the nail gun to attach the 6x1 directly into the ceiling beams. The nails will be spaced about every 16 inches.
10. Continue this process with the 6x1 around the room. Be sure that the corners fit tightly.

11. Starting at the first section again, apply a strip of wood glue on the unpainted side to the 3x1 poplar and attach it to the 6x1. Again, make sure it is flush with the wall.
12. Nail the 3x1 poplar to the 6x1. Be sure there are no gaps between the two pieces of wood.
13. Patch any nail holes in the new molding and then repaint.