Use and Care Manual

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ST1007/12/14 15" & 20" Planers (Mfd. Since 9/17)
Workpiece Inspection
Some workpieces are not safe to use or may require
modification before they are. Before cutting, inspect
all workpieces for the following:
• Material Type: This machine is only intended
for workpieces of natural wood fiber Attempting
to use workpieces of any other material that
may break apart during operation could lead to
serious personal injury and property damage.
• Foreign Objects: Inspect lumber for defects and
foreign objects (nails, staples, embedded gravel,
etc,). If you have any question about the quality
of your lumber, DO NOT use it. Remember, wood
stacked on a concrete floor can have small piec-
es of stone or concrete pressed into the surface.
• Large/Loose Knots: Loose knots can become
dislodged during operation. Large knots can
cause kickback and machine damage. Always
use workpieces that do not have large/loose
knots.
• Wet or "Green" Stock: Avoid using wood with a
high water content. Wood with more than 20%
moisture content or wood exposed to excessive
moisture (such as rain or snow), will cut poorly
and cause excessive wear to the machine. Excess
moisture can also hasten rust and corrosion of
the machine and/or individual components.
• Excessive Warping: Workpieces with excessive
cupping, bowing, or twisting are dangerous
to cut because they are unstable and often
unpredictable when being cut. DO NOT use
workpieces with these characteristics!
• Minor Cupping: Workpieces with slight cup-
ping can be safely supported if the cupped side
is facing the table. On the contrary, a workpiece
supported on the bowed side will rock during
operation and could cause severe injury from
kickback.
Wood Types
The species of wood, as well as its condition, greatly
affects the depth of cut the planer can effectively
take with each pass.
The chart in the figure below shows the Janka
Hardness Rating for a number of commonly used
species. The larger the number, the harder the
workpiece, and the less material should be removed
in any one pass for good results.
Note: The Janka Hardness Rating is expressed in
pounds of force required to embed a 0.444" steel ball
into the surface of the wood to a depth equal to half the
ball's diameter.
Species
Janka
Hardness
Ebony 3220
Red Mahogany 2697
Rosewood 1780
Red Pine 1630
Sugar Maple 1450
White Oak 1360
White Ash 1320
American Beech 1300
Red Oak 1290
Black Walnut 1010
Teak 1000
Black Cherry 950
Cedar 900
Sycamore 770
Douglas Fir 660
Chestnut 540
Hemlock 500
White Pine 420
Basswood 410
Eastern White Pine 380
Balsa 100
Figure 22. Janka Hardness Rating for some
common wood species.