
Model G0841 (Mfd. Since 06/18)
-35-
Below is a list of wood characteristics you may
encounter when planing. The following descrip-
tions of defects will give you some possible
answers to problems you may encounter while
planing different materials. Possible solutions fol-
low the descriptions.
Cutting Problems
Chipped Grain
Problem: Usually a result of cutting against the
grain, planing lumber with knots or excessive
amount of cross grain, or using dull inserts.
Solution: Decrease the depth of cut. Inspect
your lumber and determine if its grain pattern is
causing the problem. If the lumber does not show
substantial crossgrain, inspect your inserts.
Fuzzy Grain
Problem: Usually caused by planing lumber
containing too much moisture. Sometimes fuzzy
grain is an unavoidable characteristic of some
woods, such as basswood. Fuzzy grain can also
be caused by dull inserts.
Solution: Check the lumber with a moisture
meter. If moisture is greater than 20%, sticker the
lumber and allow it to dry. Otherwise, inspect the
insert condition.
Snipe
Problem: Occurs when board ends have more
material removed than the rest of the board.
Usually caused when the workpiece is not prop-
erly supported as it goes through the machine. In
many cases, however, a small amount of snipe is
inevitable.
Solution: The best way to deal with snipe is by
planing lumber longer than your intended work
length and then cutting off the excess after plan-
ing is completed.
Cutting Problems
Wood Types
The species of wood, as well as its condition,
greatly affects the depth of cut the machine 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 higher 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 37. Janka Hardness Rating for some
common wood species.
Wood Types
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