Valley Rafter task Model

Testing the Roof Framing Geometry Propositions – Axioms on a under purlin with lip cut, lower claw, intersecting a valley rafter. The Roof Framing Geometry Propositions – Axioms work on a purlin rafter to valley rafter, however the geometric lines are reversed for the upper and lower claw lines on the purlin rafter that intersects a hip rafter. 

Notes:
  1. The Valley Rafter Claw Line,Bottom Edge of the Valley Rafter, Planes with the Top Edge of the Purlin Rafter.
  2. Intersection of Valley Rafter Foot Print Line & Extended  Purlin Rafter Top Edge Plane Line defines the Valley Rafter Claw Line.














Drawing with a purlin intersecting a hip rafter and valley rafter.



Roof Framing Geometry Proposition – Axioms # 10:
The intersections of the valley rafter roof surface line, at the foot of the valley rafter, and the profile rafter foot print line defines the valley rafter claw line for the upper claw lines on jack rafters.

Roof Framing Geometry Proposition – Axioms # 11:
The intersections of the valley rafter foot print line and the top of the purlin rafter top edge plane line defines the valley rafter claw line for the lower claw line on purlin rafters.






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