Compound-angle cuts can put your sawing skills to the test, especially when the angle exceeds your circular saw's tilt capacity. One solution is to draw the appropriate angle across the top edge of the rafter, align your handsaw, recip saw, or even chainsaw, and make the plumb cut as best you can.
Confronting a double cheek cut on an irregular hip rafter, I made a quick, logical jig to adapt my circular saw to cut acute angles greater than 45 degrees. Every angle has a reciprocal angle, easily determined by subtracting the primary angle from 90 degrees.
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