Fig. 2
From: Smart increment borer: a portable device for automated sampling of tree-ring cores
General view of the smart increment borer. a Power wrench, b gear box, c reaction bar, d expandable bar, e handle of increment borer, f rope to support reaction force, g winch socket, and h increment borer. The depicted configuration is for the sampling of 12 mm cores. Winch socket can start an increment borer by pressing the cutting edge of increment borer against the stem surface (top left). The gearbox can contain large and small planetary gears, and is able to shift the gear ratio from 1:5 to 1:118 (bottom left)