Based on a pencil sharpener!It creates a rounded shaft, useful for making Arrows and dowels . There are adjustment screws for the 32mm chisel (needed) so you can make bigger or smaller arrows. See Video of it in action here http://www.youtube.com/watch?v=tL0jMKL5U5QNot sure how many arrows this will cut before the plastic wares away with friction.Thinking about it afterwards the captive nuts could have been better placed and a little less tight, anybody want to improve on this design please do. The small output tube is the diameter of the cut arrow. The larger hole is tapered towards the output tube. The blade must be position at the top height of the output tube so when the wood reaches the tube it should already be cut to fit.The dogleg is for placing into a vice or screwing to the side of a workbench