European Journal of Wood and Wood Products

, Volume 76, Issue 3, pp 911–923 | Cite as

Comparison of three systems for automatic grain angle determination on European hardwood for construction use

  • Philipp Schlotzhauer
  • Fritz Wilhelms
  • Christian Lux
  • Susanne Bollmus
Original Article


This paper aims to sketch the research results on machine grain angle determination on six indigenous hardwoods and spruce as reference. The system widely used for softwood grain angle determination (tracheid effect) is only restrictedly suitable for hardwoods. Therefore, the systems microwave scanning and electrical field strength measurement were tested as well as the above-mentioned tracheid effect with optimized settings. The measured grain angles were compared to visually determined splitting angles (reference angles). All three machine systems give reliable grain angle values for spruce. For oak, the tracheid effect is not applicable. The reference angle splitting contains weaknesses. Nonetheless, high coefficients of determination (R2) indicate a functioning automatic measurement system. Thus, it can be concluded that for the majority of the tested species automatic grain angle determination is possible. Ash does not show satisfactory results.



This work was supported by the German Federal Ministry of Food and Agriculture through the Agency for Renewable Resources (FNR). Very special thanks go to the Austrian Forest Products Research Society (Holzforschung Austria) for supplying a microwave scanning machine and the company ATB Blank GmbH for contributing the hardware and software to evaluate the ‘tracheid effect’ on hardwood. A hand-held device for the electrical field strength measurement was supplied by the company Metriguard Inc. (USA) and a second one by the DOKA Group Austria.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Wood Biology and Wood Products, Burckhardt InstituteGeorg-August-University of GöttingenGöttingenGermany
  2. 2.Holzforschung AustriaViennaAustria

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