Workshop Tip: Drill bit locates knife hinges on curved cabinetsInsert a drill bit through the pivot hole in one half of the hinge, hold it agains tthe front edge, and scribe.
Offset knife hinges are a beautiful solution for cabinets with inset doors, but there are a couple of critical dimensions that must be dialed in for the door to line up and operate correctly. When the cabinet front and door (or doors) are rectilinear, a combination square can establish the front-to-back location of the hinges and a narrow spacer can set the hinge-side gap. When the cabinet and doors are curved, however, it’s a real challenge to properly position the straight legs of the hinge.
My solution is to ditch the square and insert a drill bit through the pivot hole in one half of the hinge. To set the front-to-back position of the hinge mortises in both the cabinet and door, hold the bit against the front edge. The hinge-side gap is set as usual, by placing a narrow spacer between the hinge and the cabinet side, and then aligning the end of the hinge with the end of the door. Because the hinge’s pivot point is what matters, it makes no difference how the hinge legs are aligned. Just pivot them so they look good, scribe around them with a marking knife, and cut the mortises.
—JEFF PULS, Wildwood, Mo.
Illustrations by Dan Thornton
From Fine Woodworking issue #297