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Tensions in the wood can
sometimes result in similar
symptoms as faults in the
cutting equipment.
C. Tensions in the
wood
The M7 sawmill can only saw
straight. If the wood grain twists
during sawing, precision will be
lost. Tension can cause large
variations in measurement.
Broad leaved trees have greater
tension than do evergreens, but
even the latter can have
problematic tensions. One
example is in trees that have
grown on sharp inclines. In such
cases a whole group of logs
can be hard to saw.
Tensions can also arise in
storage. If the bark and top
segment begin to dry, the whole
surface will begin to shrink. In
such a case, when one side is
trimmed, the log may bend
slightly.
It is easy to discover tension in
logs that leads to measurement
errors. Each time you pull the
saw back, you can read what is
happening in the log. As long as
the guide bar continues to lie
just above the newly sawn
surface, the log has not bent.
However, if a spaces show up
between the guide bar and the
sawn surface or if the guide bar
is pressed upwards, it is time to
plan how the next cut will go to
reduce the tensions.
When sawing from the top
towards the bottom, the wood
has a tendency to sink at the
ends pulled by its own weight.
This is especially true if there is
large root-end growth. If this is
true, then it would be best to
turn the log after passing
through the centre and saw the
rest of the material from the
other side.
Some tips for avoiding the
effects of wood tensions.
1. Cut wood with tension in
as short lengths as possible.
2. Work around the log,
sawing all sides in order.
3. Special arrangements
may be needed in order to get a
perfect measurement on the
last board of a log. One effective
way is to saw the last cuts
using a recently sawn board as
support.
Demands on precision
We are convinced that the M7
Wood Workers Mill provides as
good or better results as other
sawing methods. A large
number of users of the Logosol
sawmills have reported that they
have never had better wood
products than those they have
sawn themselves with their
Logosol mill.
However, it is natural that we
also meet customers who want
to improve on the precision. By
now we know that variations in
sawing results can have many
explanations. The choice of raw
material is vital. Cutting good
boards from short, sturdy logs
is considerably easier than
getting the same results with
thin, long ones. Tensions
caused by storage or place of
growth can cause problems.
Some tree types cause more
problems than others. The
reasons are many, including
how much time is available.
Sawyers with unlimited time
have a greater chance to
succeed than those whose time
is short.
The precision requirements also
vary. A result that is satisfactory
for someone sawing boards for
rustic fence posts may not be
good enough for someone
sawing boards to be used in
construction without being
planed.
If you have gone through the
various steps for adjusting the
M7 sawmill, checked the cutting
equipment and observed the
effects of tensions in the
wood,but still do not get the
sawing results you expect,
contact us at Logosol. We have
years of experience and can
always help you find solutions to
problems you may have.
Cutting equipment
The Logosol PMX chain pro-
vides for rapid ripping with a
narrow kerf. But it is more
sensitive than normal chains.
Still, if you keep the cutting
equipment in trim, you will get
the right measurements, the
sawing will be quicker and the
cutting equipment will last
longer.
File before it slows down
You will sense that the chain is
loosing its edge by the fact that
the sawing slows down, the
guide bar gets hot and the feed
is harder. Stop sawing at once!
At this point it’s really too late to
file. Sawing with a dull chain
exposes the sawing equipment
to great wear and tear. You
