Stainless Steel Guided Edger Saws

Stainless steel circular saws for gang and board edger applications are being used with excellent results in several mills today. Stainless saws cost more than either conventional steel or hard chrome-plated saws. But the properties of stainless often make it very cost-effective. The advantages of stainless are:

• This corrosion resistant material nearly eliminates plate wear in guided edgers. Even acidic woods, such as cedar and oak, do not degrade stainless steel.
• Filers report fewer tip loss problems when silver soldering carbide or welding Stellite tips. Stainless steel is less susceptible to damage from heat during normal soldering, welding, and annealing than regular saw steel.
• They require less time to restore to top running condition. Stainless can take more side loading before bending or stretching because the yield strength is higher. Stainless steel also exhibits lower "stress relaxation" (that is, it holds tension better) than saw steel.
• Unlike chrome, there is no plating to peel from the saw plate causing guide wear.
• Gullets stay sharp and square, continuing to chamber the sawdust better than conventional steel after many runs, even if the gullets are not regularly "gummed". (Gullets of stainless saws must be ground with care to avoid cracks)
• Stainless works especially well with automatic circular saw levelers.
• Stainless is much harder than conventional steel, typically Rockwell "c" 49-51 hardness.

Pat Shima, filing supervisor at Weyerhaeuser’s Green Mountain sawmill in southwest Washington state, began comparing stainless to chromed saws after a McGehee curve sawing gang edger was installed in 1998. His goal was to increase the life of his 19" diameter x .100" plate (480 x 2.5 mm) saws by reducing wear on the plate and in the gullet. He reports that the side forces of curve sawing quickly wore the chrome plating from the saw, while the stainless steel plates have run more than one year with virtually no wear in either the plate or gullets. He states that while the saws were initially more difficult to level and tension, they consistently come back in better condition than conventional saw plates.

Chris Smith of Swanson Superior Lumber in Noti, Oregon, echoes Pat’s comments. Chris ran 22" diameter x .083" plate (560 x 2.1 mm) stainless saws in a Schurman 15" (380 mm) double arbor gang (one of the largest double arbor edgers on the west coast). After 32 months, the stainless saws had only .0005" (.012 mm) of plate wear. He also says that although the stainless saws were initially more difficult to level, they retain their flatness and hold their tension better than conventional steel saw plates. He also reports fewer chill line breaks behind the Stellite tips with the stainless plates.

California Saw and Knife Works has been developing stainless steel saws since 1994. One of the obstacles they have had to overcome was consistently delivering a plate that was flat enough. This was true especially in diameters larger than 20" (500 mm). The plates were not as flat as regular saw steel after the manufacturing process and were much more difficult to level.

This problem has been overcome by a combination of improved manufacturing processes and by using Armstrong circular saw Levelers at their facilities. The Levelers were installed at both Langley, BC Canada and San Francisco. They are used to level saws that would not meet their specifications for flatness.

Cal Saw also uses the "mapping" function of the Armstrong Leveler as a quality control check. By recording the information from the graph and comparing that information over time, they can recognize and correct problems earlier. Cal Saw has been very pleased with the performance and ease of operation of the Armstrong circular saw Levelers to quickly level saws to their specifications.

Armstrong’s Product Development Manager, Tony Meiwes, prepared this feature with assistance from Warren Bird of Cal Saw. Tony was pleased with the results he achieved with stainless saws at the sawmill where he was head filer before coming to Armstrong. For additional information on stainless saws, phone Cal Saw at 888-729-6533 (USA), 888-756-5522 (Canada) or 415/861-0644.