Join Date: Mar 2018
Location: Huntington Beach, California
I put up crown molding in this house.
The house was constructed in 1962.
Financial consultants took the architects plans and re-did them.
Where I put the crown molding up, not a single wall was perpendicular nor corner 90°.
There were inside and outside corners.
I had never done any sort of crown molding woodworking or construction previously.
I made a sled for my SCMS. It held the specific crown molding just like you would be looking at it. I have no idea what upside down and backward really means. If you don't have a SCMS, get one. (Mine is an old DeWalt 703) A fine tooth blade helps but not necessary. (Irwin something or other)
Measure the corners with a good protractor and "Adjustable Bevel". Measure the angle ceiling to wall. There are two different angles between ceiling and wall in the corners.
I cut KD 2x4 at the spring angle and put these pieces up with screws into the cap top of the wall behind the wall board. This underlayment does not have to meet perfectly at the corners. Yes, it is extra work but the post work conversation with a neighbor went like this: "Wow that really looks great. Would you help me do it in my house?" "No" "I'll pay you." "No".
The angle that is going to kill you is ceiling to wall. At most it will be a degree and a half off but if you don't account for it, you'll be off by a mile.
Do all the corners first using pieces about 18 inches long. Cut these pieces flat at 45°. It is always best for the non corner pointy edge of these pieces to be against the wall. Hold each piece up and you can see which way the corner cut needs to be trimmed. On these 18 inch pieces you can trim a lot to make them perfect. They may only be 16 inches when you're done but the corners will be perfect.
With all the corners done, filling in the space between is simple. Cut these fill in pieces a skosh long. That way you are able to force them into a nice fit. Use something like TiteBond III on the joints. Try not to put nails through the joint area but rather close. My crown molding has been up for over 12 years and looks great.
IMHO the walls looked just fine without crown molding. However SWMBO said the walls needed crown molding.
I installed pre primed MDF crown molding that I bought at Home Depot. If you are installing natural wood and expect to stain / varnish, you will need a lot more care.
I told SWMBO that I would install but not paint.
Do not worry about filling gaps and nail holes as the painters will take care of that.
In furniture 1/32" is a Grand Canyon
Last edited by NoThankyou; 08-09-2019 at 12:10 AM.