Potlatch Corporation is a century old western US wood products company with 1.5 million acres of its own timberland, a situation that keeps it in business. Many others, dependent on federal timber, were forced to close after preservationists’ pressures tied up federal forest management.
The company, with 15 mills in the US Pacific Northwest and Midwest, has been in both commodity and speciality wood products production at its St Maries plywood plant for many years. It is located in sparsely populated northern Idaho. During the past year’s booming construction panel market, the company has even produced sheathing when that product’s price was inflated as a result of the rocketing OSB market. But that is an exception.
Annual production is 150 million ft2, 3/8in basis, of plywood and veneer.
Tightly tested, high grade veneer for laminated veneer lumber is an important product sold to other producers. The veneer production is consistent with Potlatch’s trend toward making speciality products and shifting away from conventional construction plywood, which is losing market share to less expensive OSB.
Potlatch means ‘gift’ in the Chinook jargon which native American Indians and fur traders developed to communicate in the early 19th century.
The mill’s scenic setting could be considered a gift. It borders the shadowy St Joe river, a transportation artery in earlier days, and links with an extensive lake system. An adjoining sawmill shares dry land deck and debarking facilities.
Greg Cooperrider, who manages both the plywood mill and sawmill, said: “We’ve focused our operation here on sanded industrial grade. We have a good log supply and a good work force. We’ve been pretty successful at making quality plywood. We’ve taken a little bit of the sheathing business coming along, but we’ve stayed pretty much sanded.”
The situation is fairly well explained by the financial figures. Company communications director Mike Sullivan said: “Potlatch’s net plywood sales fell 14% in 2002 to US$34.9m. Last year the company’s net sales of OSB rose 12% to US$187.3m.” Potlatch manufactures OSB in Midwest mills.
But Potlatch is far from single-minded. It has experimented with many veneer and lumber products and has even given thought to producing an impregnated flooring product from some of the output from its 17,000 acres of poplar plantations.
Another studied speciality is LumaPly, foil faced on one side to minimise heating and cooling.
The mill’s average log diameter has dropped from 13in to 11in in the five years Mr Cooperrider has been in residence. The supply, coming from a 100-mile radius of the mill, is 70% Douglas fir with the balance in larch and white fir. Eighty per cent comes from company-owned lands.
The arriving supply is divided nearly equally between rail and truck transportation. Logs are unloaded by two LeTourneau machines. Caterpillar 980 front end loaders also serve the mill and yard.
The plywood mill will use 42 million board feet of logs in 2005, according to mill superintendent Bill Kopp.
The Cat or LeTourneau machines feed the 35in Nicholson ring barker, followed by a single 6ft circular saw which cuts logs to peeler lengths. The blocks go to the dozen hot water vats for 18 hours. Overhead hoses feed 140°F water. This comes from steam heated heat exchangers. Hog fuel heats the supplying boiler.
Potlatch installed a Metriguard unit two years ago to segregate the high strength material marketed as LVL veneer. Mr Cooperrider said: “Our logs fit the LVL market quite well because of their tight knot structure and the inland species with high MOE [modulus of elasticity].”
A Caterpillar 950 machine transfers the steamed blocks to the log deck feeding the Coe x-y charger which, in turn, serves the Coe lathe with Premier retractable spindles. The large spindle is 61/2in with a 21/2in smaller spindle. Cores kick out at 31/4in. A Coe trash gate diverts unusable roundup destined for hog fuel.
The veneer ribbon flows onto three 110ft trays before transiting the Ventek scanning system and the Durand rotary clipper. A Durand diverter directs 54in pieces to a Durand five-bin stacker. Randoms and fishtails go out to the green chain with three manual sorters.
Four longitudinal Moore steam-heated 22-section dryers dry the output; one sixdeck and three four-deck. These have Durand-Raute feeders and out feed. “We keep our moisture content below 10% because of the industrial panels. We don’t want any warping,” Mr Cooperrider explained.
Two dryers are manually sorted, with two pullers per dryer. The larger dryers, which handle 54s, output to a Ventek scanner segregating the material for a nine-bin Durand stacker. Six Raimann patchers upgrade the veneer.
Three Durand composers fabricate sheets for a Durand Raute automatic five-bin curtain coater lay-up line that can produce three- to nine-ply. The line uses Dynea resins.
Laid-up panels are pressed in a Williams- White 40-opening press and a 30-opening Columbia unit. Both are preceded by Coe pre-presses. Two putty lines follow.
A Globe saw line with standard panel turners trims the panels to standard size. A synthetic patch line, Globe tongue and groove machine, and Smithway six-head sander follow.
After Signode automatic strapping, bundles are loaded on box cars for rail or truck shipment in equal quantities.
The mill produces a good deal of underlayment and solid core A-grade marine ply-wood.  This must be manufactured from all Group 1 wood with solid core lines.
The operation, including office staff, has a total of 195 employees. The green end runs two 10-hour shifts while the dryers run three eight-hour shifts.