Technology, Evolution, Innovation and the Truss Industry

The truss industry has benefited greatly from the advances made in computer programs to run everything from design and engineering software to laser guided table setups. There are saw machines that run on floppy discs generated by sophisticated software, optimizing the cutting for little or no waste. The operator just feeds in the lumber and catches the cut parts. Quite a change from the “good old days” of the ‘70’s when a designer’s best friend was a book written in 1906 by C. K. Smoley called “Smoley’s Parallel Tables of Logarithms and Squares”.


This book was filled with nothing but numbers (all hand calculated I might add), which when applied properly, would allow the user to create cutting sheets for a roof system. The accuracy of these numbers was astounding for such an early time in the history of carpentry. We designers used this book for many years to hand calculate all the parts of every truss.

Clary Corporation, a major manufacturer of saw machines in the ‘60’s and ‘70’s, compiled a web cutting book, which gave accurate web lengths and angles for a designer to copy. 4/12, 5/12 and 6/12 pitches I seem to remember. A good designer could figure the angles and lengths for higher or lower pitches using “Smoley’s” and the templates from this book. Both of these books, in a busy plant, became so tattered over time, they had to be replaced.

The next step in the evolution of technology was a programmable calculator that would print out a numbered list of all the parts of a truss. Anthony “Tony” Arce of Arce Engineering, created a program on small magnetic cards that would program a Texas Instrument “TI-59” calculator.


What a huge step up in design technology! Each truss was input individually by the designer and a cutting list was created on heat sensitive paper like an adding machine tape. You could change quantities as needed. It would generate cutting lists for any truss shape input, including tail bearing, tray and scissor trusses. Other companies like Gang-Nail , Clary, Alpine and MiTek followed suit and began competing for the business.

Most of these companies have been swallowed up the 2 major players, ITW and MiTek. The software they generate are the best in the business, making life easier for us designers. You can generate whole house views in 3-D. Multi-level buildings, all on the same layout, can be viewed in the field on a laptop or tablet, resolving any questions or conflicts before manufacture, thus saving thousands of $ in repairs or rebuilds.

To us veterans, who have been involved in the evolution of the component industry, if you didn’t embrace the changes in technology, your career was short-lived. I worked for a company that would allow me to only generate a cut sheet for tops and bottoms. All the webbing was laid out on the table, cut with a skill saw and used as a template to be given to the sawyer on a Dewalt pull saw. The first web cut sheet I printed out and handed to the sawyer, he wadded up and threw in the trash. Needless to say, his career, as well as the plant itself, was short.

What can we expect from technology in the future? Maybe we can just scan in the architect’s drawings and push a button and the computer automatically creates the drawings. I have a feeling BIM will be making a dynamic impact very soon as well. I can’t wait to see.

Richard Gould – Design Administrator

Gould Design, Inc.