Stability
in wood is related to moisture content and annual ring direction. Many
manufacturers choose radial material for less shrinkage and swelling ratios and
uniform shape change avoiding deformations especially for layered and joined
materials. Sawmill operators usually prefer quarter sawing diagram to obtain
radial boards from logs for this purpose. However, quarter and another diagrams
give solutions for only boards that have larger dimensions than sticks, which
are commonly used layered materials.
In
this study, radial stick sawing optimization from logs was aimed. For this
purpose, commercially preferred logs with 200mm, 300mm, 400mm and 500mm
diameter, and cylindrical shape, were drawn in CAD program. Commonly used
sawing diagrams (live, quarter, around) were tried empirically basing on cross
sections. However, studies showed that when tangential boards were sawn to
obtain radial sticks, all sticks could not be radial due to annual ring
direction, especially at the end of boards. Therefore, some diagrams were
modified to obtain maximum radial stick yield.
Results
showed that the radial stick yield can reach 57,8% and the yield increment
reached max. 28,9% (12,97% in average) when the all diagrams for all logs were
considered. Especially around sawing method gave maximum radial stick yield. It
is originated from the diagram, which normally gives radial sticks from
tangential boards. Furthermore, modified sawing diagrams gave better yields
from commercially preferred diagrams. However, sawing process is becoming
extended and complicated with them.
Primary Language | English |
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Subjects | Timber, Pulp and Paper |
Journal Section | Research Articles |
Authors | |
Publication Date | June 30, 2019 |
Acceptance Date | November 20, 2019 |
Published in Issue | Year 2019 Volume: 1 Issue: 1 |