Electronic Timber Grading

The CSIRO has developed SpeedGrader, based on microwave technology which is used to scan timber for additional properties such as hidden knots.

SpeedGrader looks inside the structure of air-dry timber up to 50 mm thick, and measures the size of natural features such as knots, slope of grain and juvenile wood, that affect timber quality.

The scanners are low-powered, around 0.15 mW (much less than the power of the average torch battery), and are safer than scanners based on x-ray technology.

Using microwave technology means fast scanning. SpeedGrader can look along a length of sawn timber at the comparatively high speed of 15-20 km/hr, while it is being processed in a modern high-speed mill, and there are no severe limitations for increasing this speed in the future.