When you say the RSK Mk1 is edged at 30 degrees, do you mean 30 each side so that the total angle is 60, or 15 each side so the total angle is 30?
I ask because I've just bought a Gatco Edgemate system. It offers angles from 11 to 29 degrees. It doesn't even go up to 30, and says 29 should be used for cutting carpet etc. By eye 29 degrees looks like the angle from the stone to the blade on one side - the stone is guided on a rod, and if you hold the blade horizontal the rod makes a 29 degree angle to it.
I am wondering if the 30 degrees you recommend is measured differently, namely taking the total angle from one side of the blade to the other, rather than to the horizontal. In which case it would correspond to an Edgemate setting of 15 degrees.
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