I know there have been a few threads lately about spokeshaves in general, and some about cigar shaves in particular, and at least one a while back about sharpening the blade on cigar shaves, but I don't recall anything recently about adjusting the blade on a cigar shave. You can find some discussion of the topic at various sites, but I found that some of it isn't very helpful. I have no idea if my technique is "right," but it works for me, at least using the Millers Falls #1.
Spokeshaves are sometimes described as equivalent to small planes. For a cigar shave that analogy goes only so far, but I'll start out with that frame of reference and refer to the flat section on the outside of the body the "sole," the leading edge of it (i.e., the edge furthest away from the blade) the "toe," and the other edge the "heel." (No idea if that's the traditional terminology.) To get very fine shavings, I first set the edge of the blade so that it is coplanar with the sole, and then rotate it just a bit toward the sole, which moves the edge a skosh higher than the plane in which the sole lies (i.e., higher with the shave held so the sole is on top). I've tried to put a number to "skosh" using feeler gauges, but getting a number is difficult for a reason I'll discuss in a minute. The picture shows my Millers Falls #1 with the blade in that position.
Notice that the mouth looks fairly wide the way I have the blade adjusted. Here's where the analogy to planes or other shaves with adjustable mouths falls apart. With the cylindrical geometry of a cigar shave, tightening the mouth also increases the distance between the edge of the blade and the plane in which the sole lies, with the result that tightening the mouth actually produces thicker shavings.
On occasion, when I'm trying to shave a very tight concave surface, I'll adjust the blade in the opposite direction from what I've described above, so that the edge of the blade is below the plane of the sole, although the retaining screws limit how far you can go in that direction. If you adjust the blade as I described above, when you first start a cut on a flat workpiece, only the edge of the blade and the toe of the sole will contact the wood. If you adjust the blade in the opposite direction, the edge of the blade and the heel of the sole contact the wood. Because the heel is closer to the edge of the blade, you can get into a bit tighter curve. At least it seems to work that way for me.
One more observation that I alluded to earlier: If you set the blade so that it's coplanar with the sole, in theory it shouldn't cut at all if you hold it so that the sole is flat against the wood. In practice, there really is no "zero" point, at least not on any Millers Falls #1 that I've ever seen, because the sole is slightly crowned rather than perfectly flat. I'm inclined to think that was intentional, but maybe not -- When George Wilson made a couple of blades for me a while back, he noted that there seems to have been a fair amount of variability in the manufacturing process for the MF #1 bodies. The diameter can vary a bit from one tool to another, and George even noticed some differences between the two ends of the same shave body. So it's certainly possible that the crown in the sole is a manufacturing artifact. At any rate, that slight crown is why it's hard to put a number to the skosh I mentioned earlier.
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