Oliver 2019, Руководство пользователя

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2019 Lathe OLIVERMACHINERY.NET 35 | Page
Common Woodturning Errors
Tearouts and Chipping
When performing an “uphill” cut or scraping the end grain of a workpiece with dull tools , strands of wood
fibers are lifted from the workpiece due to lack of support. The lifted wood fiber then gets bent and
snapped, tearing the wood structure.
Therefore, to create a high-quality finish, the woodturner should do the following:
•
Use sharp tools and resharpen tools often.
•
Perform downhill cuts whenever possible.
•
Cut the end grain from the side, and peel the edge/face grain after the attached end grain is cut.
Warp and Cracks
This is a common problem when turning wood that is not fully stabilized. Logs that are freshly cut down
have high water content. In addition, the sapwood of a fresh log often has a higher moisture content than
the heartwood. As water evaporates, sapwood and heartwood shrink at different rates and cause the
wood to warp and crack.
To create a product that retains its shape and form
, it’s important to ensure the blank is fully dried and
stabilized. Depending on region and wood species, fully dried wood should have a moisture content of 4-
13 percent for indoor use.
Fuzzy Grain
This can occur when turning wood with high moisture content. As the wood dries and shrinks, the grain
rises and creates a fuzzy feeling. Fuzzy grain is unavoidable sometimes due to the nature of certain wood
types. To mitigate this issue, avoid using wood with high moisture content and use sharp cutters.