Some of you may be aware that I am a stone hound, a tool builder and sometimes I test things. I noticed that what I say tends to be least well received when I've actually tested it (recently caused some posts to be deleted).
One of the things that comes around over and over and over is the boast from various folks that they will only sharpen the minimum needed to complete a task. This boast is sort of the "climbing the hill of nobility with both legs tied at the ankles" to let you know when you're reading it that the person making the claim is absolutely dedicated to results and they aren't wasting their time like you are.
This discussion is going around again on another forum as it does sometimes here, and having tested actual results of this, I changed what I used to do because I realize that the amount of effort that I expend is largely dependent on sharpening. There are two questions to answer:
* what level leads to a positive return but is tolerable (as in, I can't tolerate stopping work for 5 minutes to sharpen, or even 4 or 3, let alone some of the long routines where folks will state that stop to start with a plane is 7 or 8 minutes)?
* why don't we notice the difference in effort day to day, and if you don't notice it does it count?
The simple answer to #1 is that you get almost the entire possible return for your efforts by following your sharpening process (whatever you've developed that's fastest) and taking a very fine stone and working the smallest amount of the edge that you can manage to work. This doesn't have to be an expensive stone. It can be a $9 vial of 1 micron diamonds that will last you a decade. I hate to say it, but using a single medium stone and replacing the strop with a very fine abrasive is a positive yield. I'm a big fan of strops, but results show otherwise (as in, don't skip the fine abrasive). My cycle time sharpening is 1:20 or so for a plane iron, and 2 minutes total if I have to take apart a completely dull double iron and reset it for actual double iron use. Less for chisels.
Why don't we notice the difference? #2? Because we can compensate all kinds of ways. We can sharpen more often (more total time), lean on a plane, push the shaving thickness past where we want, etc, and then assure ourselves that we're making less effort.
What did I find in testing? Something 5 micron size in abrasive lasts about 65% as long as something finishing at 1 micron (so if I sharpen with 5 microns and then strop, which has to be fairly brisk), I'll get 65% of the footage planed before sharpening is a necessity. If I replace the strop with a 1 micron abrasive, spend the same amount of time on the very iron tip and back quickly (as in - 10 or 15 seconds), I will get, for example, 1000 feet of planing instead of 650.
But looking closer at the results, you might think that the planing is the same, just fewer feet with the coarser abrasive. It isn't, in fact. The last 650 feet of planing with the fine abrasive are actually smoother and with less effort than the first 650 feet with the coarser abrasive, and the surface result is better. The first 350 feet with the fine abrasive aren't to be seen anywhere during the planing of the latter.
I'm not the only person who has ever tested this and generated a data set. At least one other person has done a much more extensive study and found the same thing, but as a huge fan of natural stones, I thought I could find a way that they would buck this one way or another. They do not. I also wanted to find the laziest way possible to get the results so that I didn't end up with a 4 or 5 minute sharpening process, because in a typical session of shop work, I could sharpen 2 or 6 times, or something like that, depending on what I'm doing.
This isn't a matter of buying expensive gear or adding a lot of time, it's just improving results. There actually isn't any expensive sharpening gear that improves results further beyond the cheap loose abrasives.
What else is impacted?
* surface quality (uniformity and brightness)
* the occurrence of skips, etc, on pieces you're finish planing (or more specifically, the sharper a plane is, the easier it will start a cut, the fewer skips and humps you'll develop at the edges of work and then subsequently need to remove with abrasives, etc)
* the amount of effort you expend planing both downward and forward in general
One of the things that comes around over and over and over is the boast from various folks that they will only sharpen the minimum needed to complete a task. This boast is sort of the "climbing the hill of nobility with both legs tied at the ankles" to let you know when you're reading it that the person making the claim is absolutely dedicated to results and they aren't wasting their time like you are.
This discussion is going around again on another forum as it does sometimes here, and having tested actual results of this, I changed what I used to do because I realize that the amount of effort that I expend is largely dependent on sharpening. There are two questions to answer:
* what level leads to a positive return but is tolerable (as in, I can't tolerate stopping work for 5 minutes to sharpen, or even 4 or 3, let alone some of the long routines where folks will state that stop to start with a plane is 7 or 8 minutes)?
* why don't we notice the difference in effort day to day, and if you don't notice it does it count?
The simple answer to #1 is that you get almost the entire possible return for your efforts by following your sharpening process (whatever you've developed that's fastest) and taking a very fine stone and working the smallest amount of the edge that you can manage to work. This doesn't have to be an expensive stone. It can be a $9 vial of 1 micron diamonds that will last you a decade. I hate to say it, but using a single medium stone and replacing the strop with a very fine abrasive is a positive yield. I'm a big fan of strops, but results show otherwise (as in, don't skip the fine abrasive). My cycle time sharpening is 1:20 or so for a plane iron, and 2 minutes total if I have to take apart a completely dull double iron and reset it for actual double iron use. Less for chisels.
Why don't we notice the difference? #2? Because we can compensate all kinds of ways. We can sharpen more often (more total time), lean on a plane, push the shaving thickness past where we want, etc, and then assure ourselves that we're making less effort.
What did I find in testing? Something 5 micron size in abrasive lasts about 65% as long as something finishing at 1 micron (so if I sharpen with 5 microns and then strop, which has to be fairly brisk), I'll get 65% of the footage planed before sharpening is a necessity. If I replace the strop with a 1 micron abrasive, spend the same amount of time on the very iron tip and back quickly (as in - 10 or 15 seconds), I will get, for example, 1000 feet of planing instead of 650.
But looking closer at the results, you might think that the planing is the same, just fewer feet with the coarser abrasive. It isn't, in fact. The last 650 feet of planing with the fine abrasive are actually smoother and with less effort than the first 650 feet with the coarser abrasive, and the surface result is better. The first 350 feet with the fine abrasive aren't to be seen anywhere during the planing of the latter.
I'm not the only person who has ever tested this and generated a data set. At least one other person has done a much more extensive study and found the same thing, but as a huge fan of natural stones, I thought I could find a way that they would buck this one way or another. They do not. I also wanted to find the laziest way possible to get the results so that I didn't end up with a 4 or 5 minute sharpening process, because in a typical session of shop work, I could sharpen 2 or 6 times, or something like that, depending on what I'm doing.
This isn't a matter of buying expensive gear or adding a lot of time, it's just improving results. There actually isn't any expensive sharpening gear that improves results further beyond the cheap loose abrasives.
What else is impacted?
* surface quality (uniformity and brightness)
* the occurrence of skips, etc, on pieces you're finish planing (or more specifically, the sharper a plane is, the easier it will start a cut, the fewer skips and humps you'll develop at the edges of work and then subsequently need to remove with abrasives, etc)
* the amount of effort you expend planing both downward and forward in general
