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LOGOSOL F2+
When the guide bar is not tted straight
On some chainsaws the bar tting is not level,
making the bar tilt sideways. Clean the bar tting.
Place a straight and approx. 1 m long board across
the guide bar (without the chain) and check against
the guide rail. If the guide bar is tilted sideways,
place shims between the carriage plate and the slide
rails until the board above the guide bar is parallel to
the guide rail. Tensions in the wood can sometimes
result in similar symptoms as faults in the cutting
equipment.
C. Tensions in the timber
The sawmill can only saw straight. If the wood
twists during sawing, then precision will be lost.
Tension can cause large variations in measurement.
Hardwood often has higher tensions than softwood.
But tensions in softwood can also be problematic.
Trees that have grown on steep inclines, for
instance, can have high tensions. In such cases, a
whole group of logs can be difcult 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, the log may bend slightly,
when one side is sawn.
It is easy to discover tension in the wood 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,
when there is space between the guide bar and the
sawn surface, or if the guide bar is pressed upwards
when the saw unit is pulled back, it is time to plan
how the next cut should be made to reduce the
effects of tensions.
When sawing from the top towards the bottom
of the cant, the cant has a tendency to bend
downwards at its ends. This is especially true if there
is large root-end growth pulling the root end down.
Due to this, it is uasaully best to turn the log over
after passing through the centre, and saw the rest of
the material from the other side.
If you still want to saw logs with high tensions, it
can be a better alternative to use a chainsaw and a
Timberjig (SKU: 4900-000-1000) to slice up the log.
The Timberjig follows the previously sawn surface
and therefore gives better precision if the log bends.
Some tips for avoiding the effects of
wood tensions
1. Cut wood with tensions in as short lengths as
possible. By reducing the log length to app. 2.5 m,
the precision will be high even if there are high
tensions in the wood.
2. Work around the log, sawing all sides in order.
3. To get perfect measurements on the last board,
you can use a newly sawn cant as underlay when
making the last cut. Another way is to use special
accessories for the sawmill to support the ends of
the cant. If many logs that are over 3.5 m long are
to be sawn, it is best to extend the sawmill by 1 or
2 m and add one extra log lifter/log bed.
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