Dimensional inspections in manufactured workpieces allow assess the quality of the manufacturing process, in this context the quality and development of measurement systems are issues addressed by many researchers. The coordinate measuring machines (CMMs) are versatile systems, can measure complex geometries quickly and accurately. Positional errors are parts of volumetric error and affect the correct positioning of probe in CMMs or of the tool in machine tools. Faced with this, the purpose this investigation is show a method to calibrate the positional errors in a bridge-type coordinate measuring machine, this method collects data in dynamic mode and reduces cyclic errors. The calibration of positional errors was performed using laser interferometry in the “on-the-fly” mode and a method to reduce cyclic errors was applied. The highest value of position error occurred in x axis with value positive of 10μm in the position of 220mm, while in the y and z axis the higher absolute values were 2μm and 6μm respectively. From calibration and compensating of positional errors it is possible to reduce the effects of the volumetric errors in machines with axis of linear displacements as the CMMs and machine tools.

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The development of materials that offer environmental comfort inside buildings, through adequate thermal and acoustic behavior, has been as relevant as the search for raw materials of renewable origin. In this context, this study produced and characterized panels made with Pinus sp. waste materials, which were treated with a copper chrome boric oxide preservative and a castor-oil based polyurethane resin. The physical and mechanical properties of the panels were evaluated according to the ABNT NBR 14810 standard (2013). The panel porosity was investigated by scanning electron microscopy (SEM) and mercury intrusion porosimetry techniques. The sound absorption was analyzed by a reverberation chamber and thermal conductivity by the modified fractionated column method. Samples with a higher pressing pressure (4 MPa) during the manufacturing presented lower thickness swelling and higher mechanical properties in static bending. Panels made with a lower press pressure (2.5 MPa) resulted in a higher porosity volume (55.7%). The more highly porous panels were more acoustically efficient, with a sound absorption coefficient close to 0.8 at 3.2 kHz, and they had a better thermal conductivity performance.The potential of these panels for application where sound absorption and thermal insulation are prioritized is thus observed.

For greater durability, materials must withstand contact with water, making it difficult for biodegrading agents to attack. The present study produced and evaluated the heat transfer for two pressing times and the physical properties of OSB panels, produced with pinewood strands and Al2O3 nanoparticles addition. The nanoparticles were synthesized through the sol-gel-protein method and added to the resin in the proportion of 0.5%. During the pressing process, heat transfer and distribution in the central region of the particle mat were evaluated using a type K thermocouple. After its fabrication, the panels were characterized to evaluate density, moisture content, thickness swelling, and water absorption. The results obtained indicated that the nanoparticle addition caused a refractory effect in the central region of the mat, leading to a small reduction in the pressing temperature for the 600 s cycle. However, there was no compromise in resin cure, indicating good interaction of the panels with nanoparticles in water contact, for both pressing times. There was an improvement in the panel thickness swelling with the addition of 0.5% of Al2O3 nanoparticles, with all properties meeting the Class 1 indicators of the EN 300 (2006) standard.