Verkanteter Gratsparren

Verkanteter Gratsparren translates to canted hip rafter in German. In these drawings the canted hip rafter is rotated into the roof surface plane on a ground plan with equal roof slope angles and the eave angle is 60°. This example uses my Roof Framing Geometry Propositions – Axioms on a jack rafter that's plumb to the earth and the German Shiften method for locating the upper and lower claw angles from the width of the jack rafter in plan view.


























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Layover Valley Rafter Basics

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Hip Rafter Edge Bevel and Backing Angle

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Layover Valley Rafter Hexenschnitt #3

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In the book Das neue Buch vom alten Wissen der Schiftung The new book on the ancient knowledge Schiftung The new book on the ancient knowledge Roof Framing The new book on the ancient knowledge Roof Framing Geometry by Bernd Küppers I'm stuck on page 23. The geometry in the book, just doesn't return the correct miter angle for the Layover Valley Rafter Witches Cut (Hexenschnitt). I don't know if I'm drawing it incorrectly, or the BE (Bottom Edge Plane of the Layover Valley Rafter) should be drawn differently. Similar drawing at File: Kehlbohle mit Hexenschnitt.jpg There's 3 canted planes that define the Layover Valley Rafter Witches Cut Miter Angle. The main roof surface, the square tail fascia plane of the main roof and the the square tail fascia plane of the adjacent roof.  I think the problem with my geometric drawings is defining the intersection of the roof surface with the adjacent  square tail fascia plane.
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