A compound miter saw is designed to make straight, square crosscuts as well as cut mitered angles and beveled angles (or a combination of the two) with accuracy to allow for precise and proper fitting of the parts. If the saw isn't properly aligned, the cuts will be inaccurate, which can be quite obvious in some cases, such as when you need to align two mitered cuts in a corner.
If you find that your miter saw doesn't cut as accurately as you'd like (or as accurately as it once did), it's probably time for an adjustment. Follow these Miter Saw Tune-Up Tips
to get your saw aligned and cutting accurately again.
(c) 2013 Chris Baylor licensed to About.com, Inc.
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