Most common mistakes
- Assuming your first measurement is accurate
- Not using a template when many pieces need to be cut or drilled
at the same time
- Not measuring more than once
- Tape measure
- Chalk line
- Plumb bob
- Carpenter’s Pencil
Any job requires accurate measurements. Your measurements may
include (depending on your project) spaces, length, height, width,
depth, amounts (i.e. landscaping materials) and angles (i.e. crown
mouldings, wainscots, etc.). Without accurate measurements, your
project will be a sloppy one.
Obviously to get things straight and installed properly, leveling
is very important. For someone like me, who is vertically challenged,
using my eye it may look level from my height, but it isn’t.
So, leveling is key, otherwise, things are not straight, plumb or
My brother, who is in the construction field, constantly reminds
me that things are not straight: there is no such thing as a
straight wall, floor or ceiling nor are they flat. There is
no such thing as a perfect angle (otherwise crown moulding would
be a breeze to install). So, do not assume that if you take a measurement
on one side of the room it is the same on the other side.
When drawing your marks, always use a carpenter’s level.
A torpedo level should be used only when you are dealing with small
items, i.e. hanging a picture or a small shelf. My brother has taught
me not to measure from the floor up or from the ceiling down for
the reasons cited above: nothing is perfectly straight.
Mark your measurements at frequent intervals and use a long straightedge
to draw lines or your pencil dots. Check right angles with a square.
Using a tape measure
A blade that is 1 " or more wide is safer and easier to use.
When making inside measurements, add the measurement of the tape
case, usually marked on the case. Keep the tape measure straight
and level – the slightest angle will impact accuracy.
Using a Square
Squares are used for laying out work, checking for squareness
during assembly, and marking angles. The carpenter's square (framing
square) is used for marking true perpendicular lines to be cut on
boards and for squaring some corners. One leg is 24" long and
2" wide, the other, 16" long and 1 1/2" or 2" wide.
The better types have a number of tables, conversions, and formulas
stamped on the side to simplify many woodworking tasks.
Another type of square is the combination square. It
has a movable handle that locks in place on the 12" steel rule.
It is used to square the end of a board, mark a 45-degree angle
for miter cuts and makes quick level checks with the built-in spirit
Using a Chalk line
This is a string or line coated with colored chalk used to transfer
a straight line to a working surface easily and accurately. Useful
in landscape projects. Pull the line out, hold it tight between
the your two points of measurement, and then snap it to leave a
Using a Level
Levels are used to make sure your work is level (true horizontal)
or plumb (true vertical). Always use the longest level possible.
The torpedo level is 8" or 9" in length, with vials that
read level, plumb, and 45 degrees but use it for only small pieces.
A two-to-four-foot level is a must for any home woodworking project
Using a Plumb Bob
This is a heavy, balanced weight on a string, which you drop from
a specific point to locate another point exactly below it or to determine
true vertical. A plumb bob will automatically create a vertical
line when it is hanging free from the top. It is useful when hanging