bird's-mouth


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bird’s-mouth

1. A notch cut across the grain at one end of a timber for its reception on the edge of another piece, such as a wall plate.
2. The angle between two components, usually between 90 and 180 degrees.
References in periodicals archive ?
Slide the panel up the roof until the bird's-mouths drop over the top plate of the wall.
Then temporarily place an end rafter that has a bird's-mouth notch, and mark the posts for cutoff flush with the top of the rafter.
Carefully sight along the length of the rafters so any bows are place "crown up." The upper rafter ends are cut to 13 degrees (or adjusted to your project) and the lower ends rounded on their bottom edges and notched for bird's-mouths. Secure each rafter with angle-driven 3-1/2 in.
down alongside the front beam to represent the bird's-mouth to be cut later.
It's critical that you make the marks shown in Figure B before you cut out the arches; you'll need the straight edge of the board to mark the coves and bird's-mouths (the notches that fit over the beams).