Throughout the 1950s, plate manufacturers kept busy improving their plate designs, while they paid scant attention to the machinery that CMs needed to embed them. But, in the 1960s, they began focusing heavily on machinery and laid the foundation for developments that would shape truss manufacturing over the next 50 years. Three basic machine types followed: the roller, the beam press, and the C-frame. [For all images, See PDF or View in Full Issue.]
For the short-tooth plate customers, machinery wasn’t a priority, as they could get by with a wood table and roller press, which is what Ronel Corp. employed. Carol Sanford suggested little more, indicating that CMs use “a roller table where each joint is placed under 50 tons of pressure,” and he didn’t introduce his own equipment until eight years after his plate invention. During those years, he tweaked his plate design five times. Surprisingly, Sanford started with a beam-type press.
Long-tooth customers had to apply considerable tonnage to embed plates. Cal Jureit set out on the beam-press methodology. By 1960, he had about 80 customers, and all of them would be pressing his second-generation plate, which used 14-gauge steel and had 13/16” long teeth. One CM has described how he used a 20-ton press to embed Gang-Nail plates, but this clearly limited the plate sizes he could properly seat without pressing multiple times. Jureit didn’t introduce his first truss machine until six years after his plate invention, which was still two years before Sanford. It consisted of a steel framework to be filled with concrete onsite at the CM’s location, and it utilized a jig table that would shuttle through the press head. Jureit noted that nine of these tables were sold by 1964. In fact, this approach would characterize Gang-Nail equipment for the next twenty years.
In 1963, Jureit introduced his 18-gauge plate that had 9/16” long teeth, but with a much greater density, requiring a pressing force comparable to his 14-gauge design.
Bill Black, Sr. was the first to introduce a design of a C-Frame-type of multi-head machine; however, it appeared to be significantly underpowered, and it may not have been built as designed. It is likely that he also introduced a machine with a single head that could be moved by wheels or on a track to reach all joints of the truss. Walter Moehlenpah followed with a suspended C-Frame press head that was counterbalanced by the hydraulic reservoir and moved along an I-beam overhead. That machine was continually upgraded, as was his plate design.
Sanford’s first machine employed several beam-type hydraulic presses, but a few months later he introduced the pivotal development in the history of truss machinery: the roller gantry and finish roller combination. Over the next five years, he improved the table design but maintained this basic concept. Sanford’s several patents on this configuration were so effective that no one successfully challenged them, ceding a virtual monopoly to the Roll-a-Master until the early 1980s. When Sanford exited the business, he conveyed this patent to his former employees, Bill McAlpine and Charlie Harden.
The 1960s would prove to be a pivotal decade in innovation in both plate and machinery design, setting the stage for the present-day industry. Truswal would start up and Alpine would break away from Sanford. Many other fine companies were formed that brought a wide range of expertise and innovation into the industry. And the tremendous competition among all these players shaped an increasingly efficient industry going into the biggest housing boom in history.