Glulam Building: Start to Finish – Part Nine C
Welcome to our “Glulam Building: Start to Finish” series. Our goal is to provide an overview – from idea to completion – of a glulam building from the perspective of a glulam manufacturer and designer.
Part 9C: Cuts and Holes
Our glulam billet is now marked (at least on one side) with the layout of fabrication necessary to turn it into a finished member. The most obvious fabrication steps are end cuts, holes for bolts, and other cuts and daps necessary at connections.
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| Back of an arch with shear plates at lag screw holes |
Holes can be simple through holes for bolts, stepped drilling for lag screws (which involve two different hole diameters at specific depths), or countersinks. We will also shop dap and install shear plates at bolt locations which require them.
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| Complex rafter end profiles. Long cantilevers required reinforcing knife plates, countersunk and plugged bolt holes. |
Connections might also require kerf cuts for knife plates, angled end cuts, or a variety of notches and daps to make things fit. And, lets not forget about beveled profile cuts for ridge or eave beams – sometimes with varying bevels!
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| Top and bottom bevel cuts on a large, horizontally curved beam – cut with green rolling band saw in seen in background |
All of this requires a lot of specialized tools and the expertise of our finishing department to know which is right for each job. Everything from various sizes of circular saws, rolling and stationary band saws, plunge cutting chain saws, mobile drill stands, and specialized drilling, reaming, and countersinking bits. Some are standard equipment, some some we’ve made ourselves, and some aren’t even made anymore. Each project presents its own puzzle for how to accurately and efficiently fabricate.
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| Shop fitting a post and outlooker to the open knee of an arch – with a giant drill |