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Re: cutting crown molding

From: info@builderswebsource.com
Category: Carpentry and Framing
Remote Name: 209.249.198.14
Date: 23 Mar 2001
Time: 07:11 PM

Comments

Technically, the miter of an outside corner is a 135 degree angle relative to the plane of the wall. An outside corner is 270 degrees (or 90 degrees depending on how you look at it). Divide 270 by 2 and you end up with 135 degrees. However, a miter saw is referenced to zero degrees on a cross cut (perpendicular to the molding). Therefore, the angle for an outside corner using your miter saw as a guide is, in fact +/- 45 degrees offset from perpendicular center. The trick is to keep track of which end of the cut you plan to keep. You can always cut two small pieces to make sure it fits.

Furthermore, in order to avoid compound angle cuts, you need to hold the molding in the miter saw at the exact same position it will be against the wall and ceiling. Therefore, the crown should rest against the bottom and the rear support of the miter saw. If you get this position wrong, it won't line up when you install the finished product. Start with a trial length of molding and carefully position it against the wall and ceiling until it fits properly.  Make a pencil mark on the wall and ceiling, using the outside edge of the molding as your guide. Transfer these measurements to your miter saw. A piece of blue painter's tape on the miter saw makes a convenient easy-to-see guide. Be sure you keep track of which part of the crown is the top. The back side of the miter saw represents the ceiling, while the horizontal surface of the miter saw represents the wall. You may want to clamp the molding in place so it doesn't slip while you're cutting it.

If you follow these procedures and think twice before you cut, you'll make perfect miters every time. The trickiest part is how to avoid cutting it too short and wasting a precious piece of molding. A technique sometimes used by the pros is to intentionally cut each piece just slightly over sized. Then, go back to the miter saw and trim it to size, sometimes shaving off razor-thin pieces until the fit is perfect. This works best with a power miter saw. When using a hand saw, it's harder to control very fine cuts. Using a little white carpenter's glue can also help to keep your corners tight, especially if you don't plan to cope the back side. (Note that coping requires a whole different technique, requiring angled back cutting).

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