Should your honing motion for the tiny Ruler Trick bevel on the back of the blade be parallel to the edge of the blade or perpendicular to it? Does it matter?
The late David Charlesworth demonstrates the technique in his You Tube video moving the blade perpendicular to its edge, i.e., across the edge. He starts with the blade edge beyond the long edge of the stone and pulls it back “two or three times.” He states that he does not “like to trap a wire edge underneath the blade.” He then moves the blade back and forth – barely over the edge of the stone and no more than 10mm onto the stone, which is a very short motion.
In the video, he previously honed the microbevel on the front of the blade using a guide, moving the blade perpendicular to its edge. Thus, the final minute scratches on the back of the blade meet up parallel with those created on the microbevel.
Others, in fact most, as far as I can tell, execute the Ruler Trick differently by moving the blade edge parallel along the length of the stone. This seems quicker and easier. It does mean that the final scratches on the back of the blade will be perpendicular, or at least at a large angle to, those on the bevel.
Another example of technique is from the outstanding teacher, Rob Cosman, who thinks through woodworking techniques so well. He hones the bevel in a vigorous circular/oval motion with the blade edge angled to the length of the stone. He then executes the Ruler Trick moving the edge parallel to the stone.
I used David’s original method for a long time and then drifted to using the parallel method because it is indeed easier. I began to wonder if the opposite directions of the final scratches on the front and back of the blade might weaken the durability of the edge. I lately have switched back to David’s method.
Does it matter? I cannot scientifically measure it but my shop experience is telling me that, yes, the pristine edge seems more durable using the Ruler Trick in the same direction as David demonstrated.
My only real point here is that you may want to try for yourself the different methods and consider the effects.
Another question: Should you go back and forth from honing the bevel to the back? In his video, David very gently hones the microbevel, and then does the Ruler Trick, and that’s all. He does not return to the bevel.
For me, that works well if I am cleaning up an edge that is not too worn, which requires just gentle brief honing and is easy to get right. More often, especially if I want a really nice edge such as on a smoothing plane, I find myself returning to the bevel and then repeating the RT. This means having to unclamp and reclamp the blade from a honing guide, if that is what I’m using.
Again, my point is to suggest we should be aware of just what we are doing, observe the effects, and decide from there.
Next: suggestions for managing the Ruler Trick with small blades.