Sixty Years of Machines, Part IV: Early Roller Gantries

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Issue #12248 - March 2020 | Page #10
By Joe Kannapell, P.E.

The roller gantry dominates today’s truss production, but it hasn’t always done so, despite the fact that it hasn’t changed much over sixty years. The reason for its relatively slow ascendency is found in its origins and in its adaptations over this period. And along the way are some surprising lessons that still resonate.

The patent holder of the gantry, Carroll Sanford, and his engineer, Jim Pool, didn’t exercise some creative genius to apply the principle of the “ringer washing machine” to truss production. They likely saw this appliance working in their homes, as did most Americans (this writer included) in the 1950s. But Sanford did have the foresight to gain a patent on this technology in 1965, which effectively barred competitive roller systems during its 17-year duration. While he retained the two roller “ringer” functionality in his finish press, he omitted the bottom roller on the gantry head. In its place, heavy steel tables and the familiar railroad track were employed to resist the pressure of the gantry. Some maintain incorrectly that this omission created the necessity for a finish press (see Part V next month).

Sanford’s patent drawings contain some surprises, as his jigging tables have much more in common with C-clamp pedestals than modern gantry tables (shown here and below [see PDF or View in Full Issue]). The original Sanford walk-through tables facilitated waist-level operation, unlike current systems. And it also minimized material handling distances; cut parts were stocked immediately adjacent to their location in the truss. It may be said that the Sanford jigging derived from the pedestal model, as the C-clamp design was patented three years earlier.

The Sanford Gantry, in its original configuration, changed our business like few other machines. Here was the first system capable of building the most complex trusses with an efficient material handling system. Early adopters, such as Dave Chambers and Carroll Schoffner, both dominated their markets using Sanford’s “new technology.” When Chambers saw the incredible output improvement of his night shift after installing the gantry, he told the shift manager, Don Hershey, “If you can do that on the day shift, I’ll make you a wealthy man.” Of course, Don went on to become an icon in our industry, and his sons, Ben and Keith, continue his legacy. Similarly, Carroll Schoffner leveraged Sanford’s machine in each of his multiple plants to nearly control the truss market in the Southeast. Interestingly, Mr. Schoffner told me that he made a strategic error when he revealed his methods to Dick Rotto during a plant tour (perhaps helping Rotto’s Trussway master production as detailed in Part III: Table Presses). Mr. Schoffner was proud of his highly efficient plants, and apparently so was Universal Forest Products in agreeing to pay a record $100 Million for them.

That improvements to Sanford’s original design were needed is obvious as shown in the two patent diagrams here [see PDF or View in Full Issue]. Both depict common trusses, which ruled that day. However, as the number of joints increased, and the distance between joints (as in raised heels and tray trusses) decreased, these jigging systems struggled. In fact, the Sanford system was much less advantageous, as the steel plates shown in Figure 11 in the upper drawing were much harder to move during setups than pedestals (see the lower illustration). Yet both of the above contraptions beat solid gantry tables in one major aspect: material handling. Both allowed cut parts to be located immediately adjacent to their ultimate position in the truss. Once the jig has been set and the chords and webs stocked, the time required to handle lumber and plates would dwarf the time required on a solid table gantry.

But, as will be shown in Part V, the versatility of solid tables, and their continual jigging improvements, would facilitate the ascendency of the gantry. However, the progression may have been much faster, if not for the unsteady role of the inventor. When I first encountered Carroll Sanford in 1971, he seemed the dominant force in our industry, seated at the head of the table of TPI members. But he didn’t fit in. Here was an open-collared, medallion-wearing architect flanked by conservatively attired engineers and businessmen. Like many of the creative class, Sanford wasn’t enamored with day-to-day details, and gradually lost control of his business. By the onset of the severe recession of 1974, he had sold his gantry system to his former employee, Bill McAlpine, and was out of our business. And since McAlpine and his partner, Charlie Harnden, were in start-up mode, it took them a requisite number of years to take their newly christened “Roll-A-Master” nationwide. Adding those years to the years Sanford didn’t champion his system delayed the gantry’s widespread acceptance until nearly the end of its patent protection.

P.S: Though only faint traces of the name “Sanford” are heard (as in “Sanford Gantry”), Carroll Sanford deserves much acclaim, perhaps a belated SBCA Hall of Fame recognition. Even more significant than his machinery was his invention of the short-toothed connector plate, which closely resembled today’s (watch for an upcoming series on plates). And perhaps more impactful was his early foray into truss software which enabled his former associate, Robert Brooker, to pioneer PC-driven truss design. Thus, this largely forgotten pioneer left an indelible mark on the entire scope of the truss business: truss plates, machinery, and software.

Next Month:

Part V: The Gantry Wins

You're reading an article from the March 2020 issue.

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