A good number of spinners turn their own wooden spindles with wood turning tools. And in wood turning, very sharp tools are essential.
A group such spinners on Raverly were advocating "grinding and burnishing" as a way of getting a good cut with tools made of high speed steel. I did research on the topic, concluded that grinding, sharpening, and honing produced a much superior edge.
I reported my research, and was promptly bashed by big bunch of the spinners. I gave peer reviewed citations that they did not bother to check. I cited names of engineers /spokesmen at the tool making companies that other spinners did not bother to contact. The spinners just talked to each other and bashed me. I find this a typical MO for spinners.
In the old days, wood turning chisels were made of carbon steel (CS), which has good ductility and a fine grain size. Think of CS as having a grain the size of peas. Modern wood turning tools are made of high speed steel (HSS). If CS has a grain the size of a pea, then HSS has a grain the size of tennis balls. HSS has been used for industrial purposes since 1910, and is very well understood. It came to the retail market as the hones needed to sharpen HSS became available in the 1970s.
A fine edge on CS does not last long when used for wood turning, so a common practice was to grind an edge, and burnish it over resulting in an edge the thickness of a pea with a known cutting depth. This can produce a good quality cut. HSS that is ground and burnished results in a cutting edge the thickness of a tennis ball, but which is brittle and tends to shatter, resulting in a (microscopically) rough edge that produces a poor quality cut. However, even such a poor quality cut is much better than "dull" HSS that has not been recently ground or sharpened. Grinding and burnishing is better than nothing. And this seems to be where the myth of the spindle makers come from.
However, when HSS is ground to shape, properly sharpened, and honed, the grains are cleaved resulting in a strong, uniform edge that is only a fraction of a pea in thickness, and which produces a superior cut compared to CS. I often make temporary tools from inexpensive HSS. Ground, sharpened, and honed, these very cheap tools can produce excellent quality cuts.
When I use a freshly sharpened and honed a wood chisel for a final cut, mostly, I do not even bother to sand. Sand paper coarser than 600 grit will just roughen the wood. Mostly I use sand paper when I am fitting a tenon or snug box cover.
I grew up sharpening tools on bench grinders. I have an industrial tool grinder. However, I grind and sharpen my wood turning chisels on a Sorby Pro-Edge. Then, they are honed with a diamond hone. Yes, it is expensive, but it saves my chisels, it saves the cost sand paper, and not sanding reduces dust in the shop. Special tools are ground to shape on the industrial grinder, but they are sharpened on the Sorby. Then, they are honed by hand.
I also have CS scrapers that I grind on the industrial grinder and burnish. It is technique that I understand and use -- just not on HSS.
Five of the 10 best spinners that I know are also expert wood turners. These 5, all hone their HSS wood turning chisels.
So why did that thread on Raverly need to bash me? Yes, I challenged them, but they should have done their homework and gotten their facts correct before I got there. They were telling me that they had 20 years of expedience, and that I had less, so I should defer to their expertise. Twenty years is plenty of time to do one's homework. Experts do their homework.
I know a limited number of spinners, and most of them are so talented, and so competent, and so nice, that I do not understand how there could be a bunch of readers on a spinning thread at Ravelry without somebody saying, "Hey guys, honing HSS works!" or somebody backing me up on where twist is inserted in a flyer/bobbin assembly.
.
A group such spinners on Raverly were advocating "grinding and burnishing" as a way of getting a good cut with tools made of high speed steel. I did research on the topic, concluded that grinding, sharpening, and honing produced a much superior edge.
I reported my research, and was promptly bashed by big bunch of the spinners. I gave peer reviewed citations that they did not bother to check. I cited names of engineers /spokesmen at the tool making companies that other spinners did not bother to contact. The spinners just talked to each other and bashed me. I find this a typical MO for spinners.
In the old days, wood turning chisels were made of carbon steel (CS), which has good ductility and a fine grain size. Think of CS as having a grain the size of peas. Modern wood turning tools are made of high speed steel (HSS). If CS has a grain the size of a pea, then HSS has a grain the size of tennis balls. HSS has been used for industrial purposes since 1910, and is very well understood. It came to the retail market as the hones needed to sharpen HSS became available in the 1970s.
A fine edge on CS does not last long when used for wood turning, so a common practice was to grind an edge, and burnish it over resulting in an edge the thickness of a pea with a known cutting depth. This can produce a good quality cut. HSS that is ground and burnished results in a cutting edge the thickness of a tennis ball, but which is brittle and tends to shatter, resulting in a (microscopically) rough edge that produces a poor quality cut. However, even such a poor quality cut is much better than "dull" HSS that has not been recently ground or sharpened. Grinding and burnishing is better than nothing. And this seems to be where the myth of the spindle makers come from.
However, when HSS is ground to shape, properly sharpened, and honed, the grains are cleaved resulting in a strong, uniform edge that is only a fraction of a pea in thickness, and which produces a superior cut compared to CS. I often make temporary tools from inexpensive HSS. Ground, sharpened, and honed, these very cheap tools can produce excellent quality cuts.
When I use a freshly sharpened and honed a wood chisel for a final cut, mostly, I do not even bother to sand. Sand paper coarser than 600 grit will just roughen the wood. Mostly I use sand paper when I am fitting a tenon or snug box cover.
I grew up sharpening tools on bench grinders. I have an industrial tool grinder. However, I grind and sharpen my wood turning chisels on a Sorby Pro-Edge. Then, they are honed with a diamond hone. Yes, it is expensive, but it saves my chisels, it saves the cost sand paper, and not sanding reduces dust in the shop. Special tools are ground to shape on the industrial grinder, but they are sharpened on the Sorby. Then, they are honed by hand.
I also have CS scrapers that I grind on the industrial grinder and burnish. It is technique that I understand and use -- just not on HSS.
Five of the 10 best spinners that I know are also expert wood turners. These 5, all hone their HSS wood turning chisels.
So why did that thread on Raverly need to bash me? Yes, I challenged them, but they should have done their homework and gotten their facts correct before I got there. They were telling me that they had 20 years of expedience, and that I had less, so I should defer to their expertise. Twenty years is plenty of time to do one's homework. Experts do their homework.
I know a limited number of spinners, and most of them are so talented, and so competent, and so nice, that I do not understand how there could be a bunch of readers on a spinning thread at Ravelry without somebody saying, "Hey guys, honing HSS works!" or somebody backing me up on where twist is inserted in a flyer/bobbin assembly.
.
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