Whether you see woodworking as an art or a craft, your finished piece begins
with a great piece of wood. As a woodworker, buying wood can be a challenging
experience. You have to think about a lot of details such as the grade and cut
of the wood and the way it's sized. The following sections help you make sense
of these details.You may also want to know the info about the softwood balsa . Here to know
more.
Take a pencil, measuring tape, scrap paper, small block plane (to check out
the color and grain) and a calculator to the lumberyard and write down all the
dimensions and total board feet for each board. This way you can double-check
the salesperson's calculations and make sure you aren't overcharged.
Wood grades
Wood grades refer to the number and severity of the defects in a board. The
following list explains the different wood grades, according to the National
Hardwood Lumber Association (or NHLA for short).
Firsts: Very few, if any, noticeable defects.
Seconds: The occasional knot or other surface defect. Firsts and seconds are
often grouped together and referred to as FAS (firsts and seconds). These are
the grades you want for furniture building.
Selects: A few more defects, but nothing so big or frequent that it can't be
cut out. Avoid this grade for fine furniture, though, because it adds more work
to the process.
Four grades of Common (#1, #2, #3a, #3b): Too many defects to use for
furniture.
Types of wood cuts
How wood is cut affects its quality. The following list explains the types of
cuts:
Plain-sawn: The most common boards at your lumberyard. They have growth rings
that run less than 30 degrees against the face of the board. The face grain
looks somewhat circular and wavy.
Rift-sawn: These boards have growths rings that meet the face between 30 and
60 degrees. Rift-sawn boards have a straight grain pattern as opposed to the
circular pattern of the plain-sawn boards. They're also more stable and more
expensive than plain-sawn wood.
Quarter-sawn: These boards have growth rings not less than 60 degrees from
their face and a straight grain pattern with a flake or ribbon-like figure in
the wood. Quarter-sawn boards are more stable and expensive than the other types
of boards and you can only find them in a few species of wood, such as white
oak.
Wood defects
It's okay to buy wood with knots, splits, cracks, and checks. These defects
affect only a small area of the board (if they exist over the majority of the
board, don't buy it), so you can plan your cuts around them. Avoid boards with
warps, twists, or bows. It takes a lot of time to flatten a board that has one
of these defects. To test for these defects, place one end of the board on the
floor and hold the other end to your eye. The board should be straight and true.
If not, leave it there.
Sizing up the wood
Wood is sold two ways: dimensional and by the board foot:
Dimensional wood is smooth on all four sides, cut to precise widths and
thicknesses, and is sold by the linear foot or the board.
Wood sold by the board foot may or may not be smooth on all sides and only
one edge may be square. A board foot is a board that is 1 inch thick (called
4/4) by 12 inches wide by 1 foot long. To figure out how many board feet are in
a piece of wood, multiply its length (measured in feet), width, and thickness
(measured in inches) and divide this number by 12. Here to know more about balsa
round, article resource: http://www.balsafactory.com/ .
没有评论:
发表评论