Lumber production and TypesLumber production and Types

Objectives Objectives

To understand lumber productionTo understand lumber productionTo understand the different types of To understand the different types of

lumber products lumber products

Lumber Production and Lumber Production and ProcessingProcessing

After trees are cut down After trees are cut down they are transported to they are transported to the sawmill. the sawmill.

The logs are soaked to The logs are soaked to prevent checking, prevent checking, cracking, and warping.cracking, and warping.

Logs are either plain-Logs are either plain-sawed or quarter-sawed or quarter-sawed.sawed.

Plain-SawingPlain-Sawing

Plain sawing: Plain sawing: Cutting the log on a Cutting the log on a tangent to the tangent to the growth ringsgrowth rings Is faster with less waste Is faster with less waste

resulting in lower cost resulting in lower cost lumber. lumber.

Produces a flat or Produces a flat or slash-grained lumber slash-grained lumber that is used for most that is used for most buildings. buildings.

Quarter-Sawed LumberQuarter-Sawed Lumber

Quarter sawing: Cutting Quarter sawing: Cutting the log perpendicular to the log perpendicular to the growth ringsthe growth rings Results in lumber less Results in lumber less

likely to warp, shrink, and likely to warp, shrink, and swell.swell.

Since quarter-sawed Since quarter-sawed edge or vertical grained edge or vertical grained boards have a prettier boards have a prettier grain, they are often used grain, they are often used to make furniture.to make furniture.

Drying LumberDrying Lumber

Seasoning: Process of Seasoning: Process of drying lumber to the drying lumber to the point where it is ready to point where it is ready to use. use.

Green lumber: Freshly Green lumber: Freshly cut lumber with 20 cut lumber with 20 percent or more percent or more moisture.moisture.

Air drying takes from Air drying takes from one to three months and one to three months and typically reduces typically reduces moisture content to 15 moisture content to 15 percent.percent.

Drying LumberDrying Lumber

Kiln-dried lumber uses Kiln-dried lumber uses a large oven or kiln to a large oven or kiln to dry the lumber to 6 to dry the lumber to 6 to 12 percent moisture.12 percent moisture.

Starting with high Starting with high steam and low heat the steam and low heat the kiln gradually adjusts to kiln gradually adjusts to low steam and high low steam and high heat to remove heat to remove moisture without moisture without creating cracks in the creating cracks in the lumber.lumber.

Dried and Planed LumberDried and Planed Lumber

Can be processed Can be processed into a variety of wood into a variety of wood products such as:products such as: Beveled siding,Beveled siding, Tongue-and-groove Tongue-and-groove

flooring, flooring, Trim, Trim, Molding, Molding, Etc..Etc..

Plywood:Plywood:

Wood product made Wood product made of a series of plies or of a series of plies or layers (3, 5, or 7) layers (3, 5, or 7) glued together to form glued together to form a 4×8 sheet.a 4×8 sheet.

By gluing layers so By gluing layers so that the grain runs in that the grain runs in opposite directions opposite directions the strength is the strength is maximized.maximized.

Particle BoardParticle Board 4×8 sheet made by 4×8 sheet made by

gluing wood chips, gluing wood chips, splinter, and sawdust splinter, and sawdust together.together.

Because it is hard and Because it is hard and brittle, it is used under brittle, it is used under countertops and in some countertops and in some furniture.furniture. it needs to be cut with a it needs to be cut with a

carbide-tipped blade carbide-tipped blade Warps quickly when it Warps quickly when it

gets wet.gets wet.

WaferboardWaferboard

Also known as OSB Also known as OSB board and chip boardboard and chip board

Made by gluing wood Made by gluing wood chips to form 4×8 chips to form 4×8 sheets.sheets.

Since it is cheaper and Since it is cheaper and more water resistant, more water resistant, wafer board is replacing wafer board is replacing plywood as roof plywood as roof sheathing and sheathing and subflooring.subflooring.

HardboardHardboard

Made by gluing wood Made by gluing wood fibers into sheets. fibers into sheets.

Since it is hard and Since it is hard and brittle, it should be cut brittle, it should be cut with a carbide-tipped with a carbide-tipped blade and it does not blade and it does not hold nails well. hold nails well. May be used as May be used as

tabletops or shaped in tabletops or shaped in long boards to use as long boards to use as siding.siding.

PanelingPaneling

1/8 or ¼ inch sheet of 1/8 or ¼ inch sheet of wood or hardboard wood or hardboard with a wood grain with a wood grain surface. surface.

Cheap paneling may Cheap paneling may be hardboard with be hardboard with wood grain contact wood grain contact paper on the surface.paper on the surface.

VeneerVeneer

Thin layer of material Thin layer of material that is glued to an that is glued to an inferior quality inferior quality material. material.

While high quality While high quality furniture is generally furniture is generally solid wood, low cost solid wood, low cost furniture is often furniture is often particle board with a particle board with a veneer wood grain veneer wood grain surface layer.surface layer.