The first factory makes the doors plywood facing. They start by loading logs into steaming basins for three days. This de-ices them in the winter and softens the wood fiber.
Inside the factory, the steamed logs line up for the debarker, a machine that removes the bark. The operator projects concentric circles and uses a laser to carefully center the log on the debarker. Positioning is crucial for two reasons.
So that as little wood as possible comes off with the bark, and to ensure the debarked log ends up perfectly cylindrical. That maximizes the amount of wood veneer a log will yield. The next step is called rotary cutting.
As the log spins, a lathe skims off a sheet of wood veneer just six-tenths of a millimeter thick. The average log yields 134 linear meters of veneer. Thank you.
Next, they unroll the veneer and cut it into sheets. Then they stack the sheets by identical grain patterns. Using a laser to position the blade, they cut through the stack to take out visual defects.
Then they glue the pieces together. To make veneer sheets for the front of the plywood door facing, the side that will show, they line up the wood's grain and other features in mirror image. For the back, the side that won't show, they assemble the defective parts they cut out earlier. They use three veneer sheets to make up the plywood door facing. They apply glue to both sides of one sheet, then sandwich it between two other sheets.
They feed the three sheets through a hot press at more than 100 degrees Celsius. In a minute and a half, the glue cures and those three sheets of veneer become a three-ply panel of plywood. Then they sand the panel.
Plywood door facings can be made from more than 15 different species of wood, from birch and oak to maple and mahogany. At the second factory, they make the core of the door. They glue together strips of wood to form the middle, then frame them with pieces of white pine.
A press pushes the core pieces together, then activates the glue not by heat as most presses do, but by microwaves. Next, they sand and calibrate the core. After the glue machine coats the core, they stick a plywood door facing on each side.
They stack a few doors at a time into a cold press for a half hour until the glue dries. Then set them aside while the glue cures for another eight hours. Next, they size the width and length to the final dimension, bevel the edges, and cut the exact height of the door. Then they inspect the door on both sides.
A machine prepares the door for hinges. Then another machine cuts the hole for the knob. Music The finishing process takes just 70 seconds per door. One side is sanded, stained and sealed, then sanded again and varnished.
The machine then flips the door over and does the same thing to the other side.