Summary: | This study consists of an experimental and theoretical investigation of the factors
controlling guided circular saw cutting behavior. The work includes preliminary
experimental studies, investigation of saw-workpiece interaction mechanisms, sawworkpiece
interaction experimental studies and development of a theoretical model.
In the preliminary experimental studies, the fundamental questions are: how do guided
saws work, and what are the most significant saw design factors? Extensive experiments
were conducted to investigate these questions. A fixed-collar saw closely follows the
theoretical expectations. A guided saw only weakly follows theoretical expectations. The
interaction between the saw and workpiece was identified as an important factor
controlling how guided saws work. It is identified as being a significant saw design factor
by experimental observations combined with industrial and previous experiences.
Interactions between the saw and workpiece are identified as key factors controlling
guided saw cutting behavior. Two aspects of saw-workpiece interaction are: 1) the
interaction between the saw body and the workpiece, and 2) the interaction between the
saw teeth and the workpiece. The first interaction type influences the cutting stability of a
guided saw compared with a fixed-collar saw. The second interaction type influences the
stability of a climb-cutting saw compared with a counter-cutting saw. Extensive cutting
tests were performed to explore the effects of the two interaction types. In general, the
experimental results supported the theoretical expectations. A guided saw was found to
cut more accurately than a fixed-collar saw. A climb-cutting saw was found to cut more
accurately than a counter-cutting saw.
A simplified theoretical model of a saw cutting a piece of wood was developed to
complement the experimental results and further support the interaction mechanisms. For
this model, the practical cutting factors were gradually added to make it more realistic. A
computer program was used to implement this model. Typically, this model supports the
interaction mechanisms and the experimental results.
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