Suka2

Purlin Rafters, Roof Sheathing or Dormer Square Tail Fascia Layover Cuts (Cutting Roof Sheathing with an Edge Bevel) Cutting Purlin Rafters from the Face Set in the Roof Surface Saw Blade Miter = arctan (sin Dormer Pitch Angle ÷ tan Main Pitch Angle) Saw Blade Miter = arctan (sin 26.56505 ÷ tan 33.69007) = 33.85451° Saw Blade Bevel = arcsin (cos Main Pitch Angle × cos Dormer Pitch Angle) Saw Blade Bevel = arcsin (cos 33.69007 × cos 26.56505) = 48.09115° or use Jack Rafter Side Cut Angle for the Miter Angle Valley Sleeper Saw Blade Bevel Angle  for the Saw Blade Bevel Angle Example Roof Eave Angle = 90.00000 SS = Main Rafter Slope Angle = 33.69007 -- 8:12 S = Adjacent Rafter Slope Angle = 26.56505 -- 6:12 DD = Main Plan Angle = 36.86990 D = Adjacent Plan Angle = 53.13010 R1 = Hip Rafter Slope Angle = 21.80141 C5m Main Hip Rafter Backing Angle = 26.34404 C5a Adjacent Hip Rafter Backing Angle = 15.56481 Valley Sleeper Saw Blade Bevel Angle = 90° - (C5m + C5a) = 48.09115 P2m = Main Jack Ra

Here's my first attempt for developing the geometry of the twisted steeple. This twisted steeple has an Octagonal base  for the rotation of the twist. It also sets on top of a square base for the connection to a church roof. Clocher tors -- Twisted Steeples -- Belfray I started off with an Octagon, 36" diameter for the circumscribed radius.   Then I used a height of 50" for the peak of the steeple and drew in the hip rafters. Then I divided the roof peak height into 5 equal heights. For the 5 Octagonal platforms. Draw in the Octagonal platforms and rotate each Octagonal platform by 22.5°. Octagonal platforms rotated 22.5°. With the  Octagonal platforms drawn in I added the hip rafters. Here's the plan view the twisted steeple. Hip Rafter Slope Angles and plan Angles for each of the Octagonal platforms. Here's the plan view of the twisted steeple with the plan view of the square base. In the next post I'll develop the geometry for the hip rafter backing angle f

Most of the time we just snap a chalk line down the hip rafter to cut the plywood roof sheathing. However, when the roof slope angle is steeper than an 8:12 pitched roof, 33.69007°, we will cut the plywood roof sheathing that attaches to the hip or valley rafter on the ground.  The easiest way to make an Roof Sheathing Stick is to lay the first plywood sheathe across the hip rafter and lay a stick parallel with the hip rafter and drive two nails next to the hip rafter.   AKA -- Okie Roof Stick,  something my father taught me. No math, just a couple of nails. To make an Roof Sheathing Stick on the ground you can use the plywood cut off dimension, included in both of my Android and iPhone RafterTools apps. Simply mark off the plywood cut off, offset, dimension and snap a line for the plywood sheathing diagonal. Then lay a stick next to the diagonal line and drive two nails next to the edge of the plywood. You can also use a framing square to layout the roof sheathing angle on the plywood