Saturday, July 25, 2015

Ancient Knowledge Tour

Ancient Knowledge Tour of Roof Framing Geometry

Sim Ayers & Billy Dillon

Saturday Oct. 17
San Francisco, California

The class has been moved to BuildZoom's office in  San Francisco

501 Folsom St, San Francisco, CA 94105,
8:00am to 5:00pm
Registration cost is $100.00

Sponsored by BuildZoom BuildZoom

Simpson Strong Tie
JLC Magazine -- The Journal of Light Construction -- Hanley Wood Company
WindsorOne -- Protected Trim

This will be a hands on workshop/class on advanced roof framing. 
Cut complex roofs like the master carpenters of Europe.

Tools required for the class:

2-45º drafting triangles
1-30º - 60° drafting triangle
straight edge
framing square (no rafter tables needed)
drafting protractor
drafting pencils
colored drawing pencils
Japanese Pull Saw (handsaw)

Optional Tools for the class, if time allows for Hip Rafter Edge Bevel:

Draw Knife
Hand Plane

Topics covered in the workshop:

Roof Framing Kernel , with fold out and fold down roof surface planes
Rule of Thales, converting degrees to radians i.e. 57.3
Eyebrow Dormers, Groin Vaults, Curved Hip Rafters  using ordinates
Scribing timbers using a French plumb bob
Transfer angles and lines to the stick (timber), grasshopper method.

Ad Quadratum -- Octagonal Roof Framing
Plumb To the Earth
Trait Car -- Perpendicular

Ad Triangulum
Hexagonal Roof Framing
Layover Valley Rafter
Curved Rafters

'L'Art du Trait'
Roof Framing 

Schräge Sparren 
Canted Rafters
French Devers de pas drawing technique
German Shadow Line drawing technique

Treteaux Angles
Rotated Hip Rafters
Roof Axis Plane
Pentagonal Roof Framing

Hip Rafter
Backing Angle
Edge Bevel
Basic Shift

Rafter Claw -- Barbe Angles
Eyebrow Dormers

The Witches Cut
Square Tail Fascia Angles

Besides the roof framing geometry, if time allows, for Simpson Strong Tie --- We'll show you how to install HDU hold downs correctly and how to nail plywood shear wall plywood correctly, when the On Center spacing is 2" O.C.

Sunday, July 12, 2015

Curved Hip Rafters

I came across this method of drawing out the curves of hip rafters in a Carpentry & Building magazine published in 1880 and thought it was pretty easy way to establish the curve of any hip rafter using this method. It can be used for the curved hip rafters on flared radius eave rafters, curved hip rafters on bay windows or a hip rafters with any eave angle.

To use this method draw the elevation view of the common rafter and hip rafter above the plan view of the radius rafters. Draw the radius/ Arc of the common rafter. Then draw equal spaced horizontal lines that intersect with the hip rafter slope line in elevation view. Drop some perpendicular line where the horizontal lines intersect the hip rafter slope line and the common rafter slope line . Then draw rectangular boxes to establish the cure of the hip rafter based off the curve of the common radius rafter.

Geometric drawing of the curve of a standard hip rafter and Octagon hip rafter  with a common radius rafter. 

Drawing for the curve of the bay window hip rafter and the curve of the hip rafter against the wall of a bay window.

Section of a Bay window in Plan View

How to draw out the arc of the common radius rafter on a bay window.

Geometric drawing of the curve of bay window hip rafter and the curve of the hip rafter against the wall of a bay window using the rectangular boxes to establish the curves of the rafters.