It is typical in processing of particleboards that the tool wear is very high. Drilling through holes in a particleboard presents big problems in providing high quality edge on the exit side of the holes. In case that loads caused by drilling holes through particleboards are higher than delamination value of the surface layer the result is delamination on the exit side of the particleboard. Loads by drilling depend on cutting parameters : spindle speed, feed rate, tool point angle and workpiece characteristics. Tool wear increases the force in the direction of drilling, and the torque around axis of drilling. Higher loads caused by drilling holes lower the quality of surfaces. We can assume that measuring the tool loads the quality of such surfaces can be predicted. We have drilled 3842 and 5365 holes on coated particleboards with 2 clockwise drilling tools, and measured thrust force with piezo dynamometer . We also determined delamination factor. The optimal delamination factor with no surface delamination is 1, coming to approximately 60N of thrust force. Crossing that line causes minor damage on surface. The drilling is sensible till thrust force reaches approximately 82N , and delamination factor 1 . 08.
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