Entering the new Millennium, the linear fed saw needed to be reborn. Though CMs had boosted productivity with bolted-on improvements to their Metra-Cut type saws, they still couldn’t keep up with automated component saws. Yet they remained an essential part of the saw shop, even though they weren’t radically different mechanically than Raymond DeWalt’s 1924 invention. And safety was always a pressing issue.
The risk of saw injuries was stated succinctly by CM Sam Yoder, as he pointed to the 80-year-old operator of his pull-saw, “He’s not very fast, but notice that he has all his digits (fingers).” Though Sam’s rural location may have escaped OSHA purview, inspectors were citing CMs across the country on two counts: inadequate enclosure of saw blades and lack of viable stroke limiters. In the 1970s, OSHA mandated that a hood completely cover exposed saw blades, as is the case in Europe. Initially, all linear fed saws were in violation. But in 1987, upon appeal from Speed Cut, OSHA allowed certain types of guarding to pass. While Speed Cut was able to beef up its guarding and pass scrutiny, the Metra-Cut’s stroke limiter proved to be ineffective and was increasingly cited because the sawyer had to walk around the table every time the saw angle changed. Later, the imported Mango Apollo Saw automatically limited the stroke, and included very substantial guarding. Despite these improvements, Mango’s documentation included a lengthy list of safety precautions that, unfortunately, actually underscore the grave risk of personal injury [for image, See PDF or View in Full Issue].
The demands thrust upon these linear fed saws continued to mount, even as bolt-on automation packages enhanced their output. The number of short pieces continued to multiply as a result of the increased prevalence of hip-ends, raised heels and tray ceilings. Ironically, as component saws became more automated, they couldn’t cut nearly as many of these pieces as their manually operated predecessors. And web saws, which could have cut them, were largely abandoned since equipment manufacturers hadn’t automated them. Thus, there was a crying need for an efficient way to cut short pieces.
Enter a motorcycle enthusiast, mechanic, and truss plant operator named Jim Urmson. Because he had to produce trusses in Florida, with the most demanding cutting requirements, Jim had a particularly compelling need for a better cutting tool. Automated component saws weren’t his answer. Their efficiency was curtailed when cutting all the short pieces that plagued Florida CMs – in the time it took to cut 5000 board feet of 4’ pieces, an Omni saw could have cut 20,000 board feet of 16’ members. And most frustrating to CMs was the fact that the Omni (and its counterparts) couldn’t cut any piece shorter than about 24”. Many of these shorts arose from the preponderance of 1’, 3’, 5’, and 7’ jacks in Jim’s market.
Though many Florida CMs desired machines that could rip, bevel, and compound cut, Jim took a decidedly contrary approach to other automation developers. Maybe because he had to, he followed the tried-and-true KISS principle “Keep it simple, stupid.” He tackled the vast majority of truss parts and largely bypassed beveling. When he had a viable prototype, he tested his approach with Florida CMs, like Howard Brennan, whose Custom Designed Truss in Pompano Beach (I will attest) had the most setups per job in the nation, then and now. When Jim’s streamlined approach worked in Florida, surely it would work even better in the 80% of the country that didn’t bevel any truss parts.
Jim also kept his saw mechanism as simple as possible. From this early photo [for photo, See PDF or View in Full Issue], note the forerunner of his up-and-down cutting action, more akin to a drill press than a linear fed radial arm saw. Here the saw blade’s momentum and cutting power is boosted by the pull of gravity on the weight of the mechanism. But here also are conventional infeed and outfeed tables, alluding to this saw’s most practical use, as a linear fed saw replacement.
What may seem commonplace today was extraordinary in 1999, the complete enclosure of the cutting chamber [for photo, See PDF or View in Full Issue]. Not only does this guarding obliterate every one of the personal injury risks listed above by Mango, but it also removes the OSHA citations, and gives CMs considerable peace of mind.
From these humble surroundings, which were even more basic than Art DePauw’s machine shop, sprang the linear saw revolution. But, unlike the slow evolution of the component cutter in Art’s day, this revolution would go forward at light speed in the new Millennium. And now Jim Urmson (founder of TCT Automation) was up against the big boys, chiefly Alpine and Koskovich, who possessed the software, engineering, and resources to overcome his lead.
Next Month:
Linear Saw Combat
Since 1970, Joe Kannapell has worked as programmer, Chief Engineer, Marketing Manager, and Sales VP for MiTek, plus 7 years at truss plants, retiring at the end of 2020.