Downstream and upstream, the linear saw continues to improve the flow of truss manufacturing. Increasingly, cutting and assembly are treated as interdependent processes and have begun to be tied together. Jim Urmson started this, others have followed, and a “cut truss-by-truss” paradigm has emerged. In the process, the (circa 1942) Lineberry Carts have become an anachronism.
In 2005, Jim Urmson added an integrated two-stage bunk-to-table system to his groundbreaking TCT. The first stage, feeding the saw, employed a better, V-wheeled Lineberry, designed for rapid reloading of bunks of lumber. And their compact arrangement foreshadowed Steve Aylsworth’s Ranger RS System (see “Witnessing Integration at BCMC”).
By arranging the units of lumber side-by-side, boards can be pulled from the end of the bunk rather than from the side. Not only does this save the picker’s back, but it also saves him multiple steps moving from bunk-to-bunk. And because of the TCT’s optimization, selecting from longer, more costly lengths can be just as efficient as pulling from lower-priced shorts. Savings also accrue from stocking fewer SKUs and handling less material. These factors combine to lower material and labor costs, and to facilitate the processing of smaller, table-ready batches, without concern for the number of carts that would have otherwise been required.
Urmson’s second stage, sending cut parts down a conveyor instead of onto carts, was pioneered by early TCT adopters, Steve Rothenbach of Forest Products and Mike White of Manning Building Supply. Today, Tim Bennett, Manning’s GM, further leverages the capacity of the conveyor by cutting mainly truss-by-truss. His sawyer stacks webs-on-top-of-chords at the TCT outfeed, bands the cut parts together, and conveys the bundle to one of two build stations. Organizing cut parts this way lessens jig setup and assembly time (see comparison at https://youtu.be/YrSCdxsffa4). The only time Bennett doesn’t cut one truss at a time is for longer runs, which he divides into batches of 10, matching the capacity of the conveyor.
Urmson’s amazing culmination of these first two stages was a robotic truss assembly line, launched in conjunction with the former ProBuild, then a $6 Billion sales entity. This automated line was developed at ProBuild’s Ocala, Florida facility and added the remaining stages of the assembly process, including splicing of chords, placement of lumber, automatic jigging, and plating (see https://youtu.be/o9tJeCCGAKI). Remarkably, each aspect of Urmson’s implementation predated systems developed in Europe and later deployed in the U.S., as follows:
- Industrial robots to offload lumber and place cut parts onto the jig table. In late 2020, Trussmatic Oy of Finland shipped their first automated system to the U.S. in which robots apply both jigging and cut parts onto an “assembly wall,” and since then have shipped several systems.
- Cam-like mechanisms to move chords into their final positions. In 2015, True House installed Randek AB’s Auto-Eye System which incorporated a conventional auto-puck system.
- Magazine-fed automated plating. The Auto-Eye System added vision technology to achieve more precise locations.
Each of these stages of truss assembly will continue to be tested and refined, and other approaches will come to market. Drexel Building Supply in Wisconsin, for example, announced a $27 Million robotic facility nearly a year ago. Others have taken a more conventional approach to improve material flow. BJ Louws at Louws Truss in Washington and Eric James at Hart Components in Texas have had great success positioning each of their MiTek Blade linear saws opposite a single workstation. They, like Tim Bennett at Manning, cut truss-by-truss and forego some of the throughput of their linear saws in return for greater gains at their truss tables.
Enterprising entrepreneurs will continue to advance automation of our industry, but at a rate dependent on the vagaries of the building cycle. As Keith Fell, retired Toll Brothers Director of Manufacturing, observed recently, “Investments in high tech manufacturing seldom survive a significant downturn.” That’s what waylaid TCT Automation efforts. But significant groundwork has been laid, experimentation continues, and the increasing automation made possible by the linear saw is inevitable.
Next Month:
Icing on the Cake