Although the Egyptians were the earliest people to glue thin layers of wood together, plywood as we know it today was first manufactured in France in the 1860s using veneers cut from logs with a rotary lathe that had been invented a decade earlier in Sweden.
Plywood gets its strength from the perpendicular layers of veneers, thus making it a versatile building material. Some of Canada’s finest plywood is made from Shuswap timber in Canoe, where Gorman Bros. now operates the plant that Federated Cooperatives first opened in 1965.
Recently, I was fortunate to get a tour of the Canoe plywood plant and learn about the advanced technology used in the manufacturing process. Since Gorman Bros. purchased the mill and forest licence in 2012, they have invested over $50 million to modernize the operation, which resulted in a vast increase in efficiency and nearly doubled the production.
Our tour began at the “green end,” where the 8-foot-6 logs arrive after being soaked in a hot water vat for six to seven hours. Here, the high-speed lathe slices off the eighth-inch thick veneer in just six to eight seconds, depending on the size of the logs, which can be from 6- to 28-inches in diameter. As the veneer moves quickly along the line, it is cut with a long knife into 4-foot-6-wide sections.
This machine measures the moisture content of each sheet to determine if it is heartwood, light sapwood or heavy sapwood, which is found on the outside of the log. Sapwood veneer that is relatively clear wood is sent through a robotic machine that cuts out the knots and inserts a patch. The piles of veneer are then sent to the driers, where the amount of time each sheet takes to move through is set by the moisture content of the sheets.
The next step in the process was most fascinating. To make the inside filler layers out of the softer heartwood, each sheet is cut into 4.5-foot-long sections, which are then rotated and joined together with glass fibre that is pressed into the wood. Resin glue is applied from the next machine as the veneer sheets pass under it, are sandwiched together and then piled into stacks, which are initially compacted under 2,000 pounds of pressure.
These stacks are moved to a machine operated by one worker who moves up and down on a lift as he pushes each sheet into a hot press that again uses 2,000 pounds of pressure for the final compaction. Then each plywood sheet is trimmed and graded, and the highest quality plywood is sent through another robotic machine that fills the knot patches with putty. Each stack of plywood is then stenciled with the Canoe brand name and then another robotic machine prints the size and grade of the wood.
Over 200 employees work in three shifts to produce the quality plywood, including 17 millwrights and eight computer programmers who keep the maze of machinery and robotics operating smoothly.
Safety is number one at Canoe, and as a result the plant is one of the safest in the province. It is also one of the most productive, efficient and pollution free operations.
In addition to renovating the green end that boosted recovery and production, which increased from 150,000 to 260,000 cubic metres, they will be purchasing a new veneer drying line, new vats and automation systems. Most importantly, Gorman’s cleaned up the airshed by adding a Regenerative Thermal Oxidizer that heats and re-burns the emissions, which has resulted in up to a 90 per cent reduction of emissions from the site, much to the delight of the nearby residents.
When Gorman’s purchased the plywood plant, they also took over the woodlands, which includes several forest tenures including a tree farm licence. The Shuswap forests are diverse, which fits well with the other divisions in the Gorman group.
Most of the Canoe plywood is made from Douglas fir. Other species, including cedar, spruce, hemlock and balsam flow to the Downie sawmill in Revelstoke or to the Gorman Bros. mill in Kelowna. After many decades of logging and recent forest fires, the timber supply is not what it once was, but nonetheless, it still provides a large proportion of the 22 truckloads needed per day to supply the Canoe plant.
Gorman’s has plans for more improvements in the future, including automating the machine that feeds the second press. As well, they are looking into more value-added systems, including producing plywood sheets up to 20 feet long, as well as fire-resistant sheets and concrete forms that have a sheet of resin on the surface.
The Shuswap is fortunate to have such a well-run plywood plant that produces quality building material used for construction primarily in Canada, with just three percent shipped to the United States.
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