derekcohen
26th October 2007, 03:44 PM
Side Sharpening and The Sharp Skate Honing Guide
by Derek Cohen
The Sharp Skate is a recent addition to the range of blade honing guides on the market. Designed by Harrelson Stanley, it is different in concept to anything else I have seen to date. There is no doubt that in discussing its pros and cons it is capable of polarizing woodworkers. It will raise a number of questions for those who are curious about how blades are best sharpened. It is definitely better suited to a certain type of hand tool user than another and, consequently, woodworkers will need to ask of themselves “who am I and what do I want from the Sharp Skate?” Lastly, regular users of other types of honing guides are likely to experience an initial frustration with the Sharp Skate. This is not a criticism but a part of the journey.
If this all sounds rather intriguing, then read on …
The Sharp Skate
The Sharp Skate is built from anodized aluminium. It has a large screw head that adjusts the blade hold down. The underside has 9 small wheels along which the Sharp Skate runs. Unlike traditional honing guides that move fore-and-aft, the Sharp Skate moves side-to-side.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/1.jpg
Another original solution is the way a blade is secured, either in square or skew mode. A frequent complaint of many guides is how a blade may slip out of a setting. Here, the underside of the hold down is both angled and ridged. The angle allows pressure to be placed across an uneven blade back, while the ridges create a multitude of fences against which the blade is aligned.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/2.jpg
At each side of the guide is a thin steel rod. When removed the hold down is able to pivot, and specific angles may be selected to sharpen skew bevels faces. There are preset settings for 20 through 45 degrees.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/3.jpg
Origins of the Sharp Skate Design
Before demonstrating how the Sharp Skate is set up and used, it is important to understand where the concept originated. Let me introduce you to Side Sharpening …
Side Sharpening
I am sure that I am not alone in having used side sharpening as a technique for many years. No doubt like others before me, I “discovered” this technique when faced with honing small and narrow blades, such as those for a side rabbet plane, which were too small to fit a guide or too small to hold comfortably and securely to freehand back-and-forth.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/4.jpg
The small blades of a Stanley #79 Side Rabbet Plane
I discovered that moving it sideways rather than front-and-back enabled greater registration area and kept the blade edge from rounding over. Hey Presto – Side Sharpening!
The first time I have seen this method documented was when I came across a DVD by Harrelson Stanley.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/5.jpg
I ordered the DVD, viewed it several times, and practiced side sharpening ala Harrelson Stanley before attempting to use the Sharp Skate. The essence of the method may be summarized as follows:
· The right hand (for a right-handed individual) is used to support the blade. Do so by holding it by the fingertips. “Take the power out of your right hand”.
· The left hand is used to sharpen. Used it like a saw… “as if the left hand is going to saw the stone into ribbons…trying to keep the hand rigid from tips of the fingers to the elbow”.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/6.jpg
I noticed that my natural inclination is to tuck the remaining fingers of my right hand under the blade. This served to take more of the weight off the left hand, which is doing all the work – pressing down the bevel face and sliding it back-and-forth.
The advantage of this freehand method is the greater degree of face support. Compare this to the traditional front-back method where the bevel face will want to roll.
· Rock the blade until it is flat on the surface.
· Use short strokes to the end of the stone to maintain registration (the temptation is to immediately take long strokes, ala a traditional guide.
The other argument for preferring the side sharpening method involves the removal of the burr that is raised when honing the bevel face. Harrelson views the burr as too fragile to remove with a front-to-back motion as this is likely to cause it to break off with a jagged edge. By polishing it off sideways for the length of the stone, the burr is encouraged to shear off cleanly. It is recommended that this take place between each stone and not only at the end.
What effect does Side Sharpening have on the bevel edge?
The question is whether striations parallel to an edge will weaken the edge compared to those that run front-to-back? Basically, how do the two methods compare?
I raised this issue with Brent Beach who, armed with his microscope, set out to obtain the necessary evidence. It is relevant to note that Brent arrived at the following conclusion using a sandpaper system and with his own honing guide, a design different from the Skate Sharp:
· Using a Stanley plane blade, the difference in edge durability with the two methods was very similar, with insignificant differences present.
From Brent’s research I am happy to conclude that both methods produced equivalent results in regard to durability of edge.
Impressions of Harrelson’s method
The DVD is well worth viewing. As expected the information Harrelson presents is more than just holding a blade and moving it sideways across a waterstone. Harrelson also provides insightful advice about using a waterstone and dealing with the burr created by the sharpening process.
Harrelson recommends working the blade along the inside face of the ‘stone, as opposed to down the center. This will wear a minute camber rather than a hollow. The reasoning here is that the blade is more easily kept flat this way.
Harrelson also recommends removing the burr on the final polishing stone after each successive stone (rather than only doing so at the end). I found that this does provide a better ability to keep track of where the edge is being honed.
He also extols the importance of maintaining flat stones, which he does after each blade. This, and the large amount of water he used, was a surprise since I was doing less of each with the same Shaptons. In following his advice I found that previous “sticktion” (stickiness) was now almost completely absent.
The bottom line about freehand side sharpening, compared to freehand front-and-back sharpening, is that it really makes the task so much easier – greater control, and a flatter bevel face.
What I will point out is that “side sharpening” is not fully side sharpening but really also diagonal sharpening. I suspect that this is one of the reasons for my flat bevel; faces – moving sideways only is likely to lead to some rounding, but less that the rounding with front-and-back since the latter has less registration. Moving the bevel face diagonally enables a flattening effect to take place. Now the question is, can one do the same with the Sharp Skate?
Assessing the Sharp Skate
The Sharp Skate was used to hone a variety of blades. These ranged in width from 1/16” to 2 ¼”, in shape from parallel plane irons to tapered chisel blades, and straight as well as skews.
Here are a few of the many:
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/7.jpg
The media used was a set of Shapton waterstones comprising 1000/5000/8000/12000 grit. These were maintained with a 10” DMT Extra Coarse diamond stone.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/8.jpg
by Derek Cohen
The Sharp Skate is a recent addition to the range of blade honing guides on the market. Designed by Harrelson Stanley, it is different in concept to anything else I have seen to date. There is no doubt that in discussing its pros and cons it is capable of polarizing woodworkers. It will raise a number of questions for those who are curious about how blades are best sharpened. It is definitely better suited to a certain type of hand tool user than another and, consequently, woodworkers will need to ask of themselves “who am I and what do I want from the Sharp Skate?” Lastly, regular users of other types of honing guides are likely to experience an initial frustration with the Sharp Skate. This is not a criticism but a part of the journey.
If this all sounds rather intriguing, then read on …
The Sharp Skate
The Sharp Skate is built from anodized aluminium. It has a large screw head that adjusts the blade hold down. The underside has 9 small wheels along which the Sharp Skate runs. Unlike traditional honing guides that move fore-and-aft, the Sharp Skate moves side-to-side.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/1.jpg
Another original solution is the way a blade is secured, either in square or skew mode. A frequent complaint of many guides is how a blade may slip out of a setting. Here, the underside of the hold down is both angled and ridged. The angle allows pressure to be placed across an uneven blade back, while the ridges create a multitude of fences against which the blade is aligned.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/2.jpg
At each side of the guide is a thin steel rod. When removed the hold down is able to pivot, and specific angles may be selected to sharpen skew bevels faces. There are preset settings for 20 through 45 degrees.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/3.jpg
Origins of the Sharp Skate Design
Before demonstrating how the Sharp Skate is set up and used, it is important to understand where the concept originated. Let me introduce you to Side Sharpening …
Side Sharpening
I am sure that I am not alone in having used side sharpening as a technique for many years. No doubt like others before me, I “discovered” this technique when faced with honing small and narrow blades, such as those for a side rabbet plane, which were too small to fit a guide or too small to hold comfortably and securely to freehand back-and-forth.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/4.jpg
The small blades of a Stanley #79 Side Rabbet Plane
I discovered that moving it sideways rather than front-and-back enabled greater registration area and kept the blade edge from rounding over. Hey Presto – Side Sharpening!
The first time I have seen this method documented was when I came across a DVD by Harrelson Stanley.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/5.jpg
I ordered the DVD, viewed it several times, and practiced side sharpening ala Harrelson Stanley before attempting to use the Sharp Skate. The essence of the method may be summarized as follows:
· The right hand (for a right-handed individual) is used to support the blade. Do so by holding it by the fingertips. “Take the power out of your right hand”.
· The left hand is used to sharpen. Used it like a saw… “as if the left hand is going to saw the stone into ribbons…trying to keep the hand rigid from tips of the fingers to the elbow”.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/6.jpg
I noticed that my natural inclination is to tuck the remaining fingers of my right hand under the blade. This served to take more of the weight off the left hand, which is doing all the work – pressing down the bevel face and sliding it back-and-forth.
The advantage of this freehand method is the greater degree of face support. Compare this to the traditional front-back method where the bevel face will want to roll.
· Rock the blade until it is flat on the surface.
· Use short strokes to the end of the stone to maintain registration (the temptation is to immediately take long strokes, ala a traditional guide.
The other argument for preferring the side sharpening method involves the removal of the burr that is raised when honing the bevel face. Harrelson views the burr as too fragile to remove with a front-to-back motion as this is likely to cause it to break off with a jagged edge. By polishing it off sideways for the length of the stone, the burr is encouraged to shear off cleanly. It is recommended that this take place between each stone and not only at the end.
What effect does Side Sharpening have on the bevel edge?
The question is whether striations parallel to an edge will weaken the edge compared to those that run front-to-back? Basically, how do the two methods compare?
I raised this issue with Brent Beach who, armed with his microscope, set out to obtain the necessary evidence. It is relevant to note that Brent arrived at the following conclusion using a sandpaper system and with his own honing guide, a design different from the Skate Sharp:
· Using a Stanley plane blade, the difference in edge durability with the two methods was very similar, with insignificant differences present.
From Brent’s research I am happy to conclude that both methods produced equivalent results in regard to durability of edge.
Impressions of Harrelson’s method
The DVD is well worth viewing. As expected the information Harrelson presents is more than just holding a blade and moving it sideways across a waterstone. Harrelson also provides insightful advice about using a waterstone and dealing with the burr created by the sharpening process.
Harrelson recommends working the blade along the inside face of the ‘stone, as opposed to down the center. This will wear a minute camber rather than a hollow. The reasoning here is that the blade is more easily kept flat this way.
Harrelson also recommends removing the burr on the final polishing stone after each successive stone (rather than only doing so at the end). I found that this does provide a better ability to keep track of where the edge is being honed.
He also extols the importance of maintaining flat stones, which he does after each blade. This, and the large amount of water he used, was a surprise since I was doing less of each with the same Shaptons. In following his advice I found that previous “sticktion” (stickiness) was now almost completely absent.
The bottom line about freehand side sharpening, compared to freehand front-and-back sharpening, is that it really makes the task so much easier – greater control, and a flatter bevel face.
What I will point out is that “side sharpening” is not fully side sharpening but really also diagonal sharpening. I suspect that this is one of the reasons for my flat bevel; faces – moving sideways only is likely to lead to some rounding, but less that the rounding with front-and-back since the latter has less registration. Moving the bevel face diagonally enables a flattening effect to take place. Now the question is, can one do the same with the Sharp Skate?
Assessing the Sharp Skate
The Sharp Skate was used to hone a variety of blades. These ranged in width from 1/16” to 2 ¼”, in shape from parallel plane irons to tapered chisel blades, and straight as well as skews.
Here are a few of the many:
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/7.jpg
The media used was a set of Shapton waterstones comprising 1000/5000/8000/12000 grit. These were maintained with a 10” DMT Extra Coarse diamond stone.
http://i13.photobucket.com/albums/a262/Derek50/Articles/Sharp%20Skate/8.jpg