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LOGOSOL CH3
PLANER
PLANING
Planing
A moulding planer does not straighten the board, it
only sizes and moulds the workpiece. The processing
part of the machine must therefore be built as short as
possible to avoid truing action. Panels and mouldings
are not normally straightened.
A surface planer makes the sides of the workpiece
straight but does not size. A surface planer must have
long tables that guide the workpiece directly over the
cutter. The board must thereafter be run through a
planer, sizing planer or moulding planer to get the
right dimensions in width and height. Normally only
shorter pieces are straightened for furniture joinery or
window manufacturing, for example.
These two types of planers should not be confused.
They each have a function that is important in itself.
Wood
Wood shrinks when it dries. Most shrinkage occurs
when the wood dries from 25% humidity to 10%. To
attain a good surface, you should not plane wood that
has higher humidity than 20%, and that is about as
dry as wood can become by outdoor drying. Ideally,
the wood should therefore be stored indoors before
planing.
Along the length of a board, along the fibres, wood
shrinks very little. In most cases it is not something
you need to take into account. Along the annual rings
the wood shrinks by about 8%, and across the annual
rings by about 5%. So it is better with vertical annual
rings in the boards.
Boards buckle and crack over time. To avoid problems
with this as much as possible, the wood should in
most cases be turned so that the core side becomes
the visible surface.
If you make cover boarding, the upper boards must
be turned with the core side outwards and the inner
boards with the core side inwards to get as dense a
wall as possible.
Results
Hard materials provide a better surface than soft ones.
Small impressions, similar to light small flames, are due
to chips that settle around the edge and are pressed
into the wood. This phenomenon increases when the
knives lose sharpness.
If the cutter marks are visible in the planed wood, it
is usually either because the knives are not adjusted
to the same height or because the workpiece is not
pressed hard enough against the table or the guide
during processing. An excessively high feed rate can
also result in visible cutter marks.
Keep the feed rollers clean of chips. The out-feed roller
is especially important because chips stuck to it can
otherwise make marks in the planed surface.
How do you find out about the knife material?
If you want to test a knife, you can hold it for a moment
against a rotating grinding wheel. If there are many
white sparks, the steel is soft. If there are a few red
sparks, the material is hard. Compare with a knife of
a known material, such as a Logosol HSS knife.
Edge angle
Logosol's planer knives have a 38 degree angle on the
knives and 20 degrees in the cutter. Some claim that a
sharper angle is better suited to hardwoods. This can-
not be considered as proven. A sharper edge angle,
on the other hand, produces a poorer planing surface.
Planing tips
• You can experiment with adjusting the pressure
on the feed rollers. If you lower the table, you
can easily access the springs supporting the nuts.
Note the default setting before you start turning
so that you can easily find your way back to the
default setting. Normally the springs should be
tightened harder on the side of the fixed cutter,
especially if narrow workpieces are planed. The
feed roller must balance on, i.e. stand horizontally
over, the workpiece and not apply more pressure
on either side.
• Never run the planer without starting the chip
extractor. Chips quickly clog couplings and hoses.
Always adjust all chip transporters. Otherwise, the
entire planer will be filled with chips, consequently
producing poor results.
• If you have a board that is very incorrectly sawn,
or if for some other reason you want to remove
a lot of wood, adjust the planer so that it only
takes as much as it can handle. Run the board
through the planer several times until you can set
the correct dimension. This technique cannot be
used if moulding knives are mounted in the lower
and top cutter.
• Try to avoid overly warped wood; it does not get
much straighter because you plane it. However,
there are no major problems with planing warped
or skewed wood.
