The Development of the Truss Plate, Part VII: Contentious Competition

Issue #15283 - February 2023 | Page #10

By Joe Kannapell

The plated truss industry went bonkers around 1961. Truss fabricators were besieging suppliers for product and were willing to try nearly any plate or machine. Plate suppliers had to conform to the new testing and QC required by TPI-60, but machinery vendors had no guidelines beyond satisfying customers. Many of these early suppliers followed the lead of Sanford and Jureit in obtaining patents to protect their inventions and their eventual sales – or so they thought. Among those were Interlock Steel in Pennsylvania, Clary Corporation in Texas, and Bill Black, Sr. in Florida, each entering the business with a unique perspective and each making their mark. [For all images, See PDF or View in Full Issue.]

Interlock Steel: Edgar Mort knew right away that a truss plate with integral nails would sell much better than those he was stamping with only holes for nails. He encouraged his CPA brother, Bob Mort, to join him in developing a truss plate business. Edgar then devoted the resources of his Standard Aluminum Co. to developing a plate, while Bob engaged Dr. Jack Ritter at nearby Youngstown State University’s Civil Engineering Lab to assist. After testing several configurations, they settled on a unique design, for which Mort received a patent in 1965. With a viable product in hand, the Morts incorporated Interlock Steel Company, and went on to become a full-service supplier of plates, engineering, and machinery.

Clary: The Clary Corporation had been a manufacturer of mechanical office machines, but somehow got into the saw business through the work of a prolific inventor, George Mayo. Mayo’s first remarkable rendition of a component cutter incorporated mechanisms that survive to this day, including a rack and pinion drive for the moveable head, and a square drive shaft for the lumber conveyor. Mayo kept innovating for the next twenty years, finally conceiving the Timbermill for Speed Cut, Inc., the first component saw with more than four heads.

Clary was also the first to provide tabular books of cutting angles and lengths, authored by future SBCA President Gary Sweatt, PE. Later, Clary persuaded Dan and Camilla Hurwitz to move to Texas to provide cutting software. Though that venture was short-lived, the Hurwitzs went on their own to create On-Line Data, the most successful independent software provider.

Bill Black Sr., father of TeeLok founder Bill Black, Jr., devised a machine to build trusses, “of unusually uniform structural characteristics.” As this was the earliest truss machinery patent granted, it was necessary to establish the advantages of offsite construction over conventional framing which, “…requires much climbing about the upper portion of the house being erected, limiting this phase of the work to the stronger and more agile carpenters.”

Unfortunately, this very detailed multi-head machine design, perhaps never built, didn’t anticipate the tens of thousands of pounds of force required to embed most truss plates. But as this concept evolved through the next 20 years, it finally resulted in Hydro-Air’s Glide-Away, which set the world production record that stands to this day (see The Last Word: Vertical Presses—The World Record, in the February 2020 issue).

The three patents described here and in my previous articles set the stage for a contentious competition to either work around or to one-up these patents. By their nature, patents required the inventor to reveal the details of his invention to the public in exchange for gaining a monopoly position for the next 17 years in 1960. For example, Mayo’s 12,800-word patent description was sufficiently detailed to enable imitators to evade it with the help of skilled patent attorneys and skeptical courts-of-law. And, over the next decades, it was the courtroom that would largely shape the future of the industry. But, in the near term, a pivotal decision was forthcoming that would become the most far-reaching.