A. Gary Katz, a finish carpenter in Reseda, Calif., and moderator of the JLC Online finish-carpentry forum, responds: Most carpenters and cabinetmakers are familiar with Soss hinges (800/922-6957, www.soss.com), probably the best-known hidden hinges on the market (see photo, left). But I've found that their small hinge backset results in poor frame clearance, which causes problems when applying moldings or mirrors above doors. Moreover, they bind if the door on the hinge side is beveled, or if they haven't been perfectly mortised at the exact same depth. They require very deep mortises, too, making the risk of running into nails while cutting with your router bit or paddle bits all too real. Also, they can't be adjusted after installation.
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