- Joined
- Sep 9, 2003
- Messages
- 2,361
I think the test is good for anybody to whom it will give confidence and comfort in their work. There are folks who thought one famous bladesmith must know what he was doing and all started using silver wire inlay in curly maple, it made them feel good about themselves and their work to do what the big guy did and in the end they sold knives! How can I argue with that? The maker, the customer, if those two people are happy, our objectives have been met.
On the other issue of KSA, I think they are an abomination spawned by an eagerness to appeal to the mall ninja types. I like specialization to do the task at hand very well, axes are axes and knives are knives, when you make a tool do too many more jobs than its original function it will do them all equally bad.
I have found an edge thickness and geometry that works very well for me (when I did the cutting competitions I always enjoyed comparing the edges in the final lineup) and I never used a flexing test to find it. The question was just re-asked about my testing. I have been asked in this thread about other tests I would use, but I was under the restriction of what tests I would use in the shop of the inquirer; under these limitations the rod thing doesn’t look so bad.
But this is my actual testing regimen:
I break the testing down into two categories- materials/processes and general practical application. The first consists of testing just the O1, L6 and 10XX I work with for its properties under the processes I have subjected it to. This consists of Rockwell hardness testing, Charpy impact testing, checking abrasion resistance and how the metal itself reacts to wear, and extensive metallographic analysis. From this I can fine tune my heat treating and forging methods to get the material alone to do what I want it to do, based upon precise and quantifiable data. The next step is practical application on the material after it is in the shape of a knife, this is for determining things like the best edge geometry, the type of edge put in, the weight and balance of the blade and any other functional aspects of the overall knife. For this the best thing to do is just use the damn knife and observe the results. But use it in a manner that resembles knife use.
The largest difference between this type of testing and the more down home approach is repeatability. If you can heat a blade to 1500F exactly and be able to hold it there indefinitely, then quench exactly the same way into the same medium again and again, and keep all of your previous treatments the same, you can then start confidently analyzing individual properties like this. To be honest the guy with a forge fire, a magnet and a bucket of oil needs to test whole lot more to insure quality control, probably every single blade should be tested to insure nothing has gone awry. If one slightest thing is off for him the only way to know is to test each blade. I know each O1/L6 blade will be 64.5HRC as-quenched and then will level off at 61.5HRC from an initial 30 minute temper of 420F. * My final long term tempers will be according to blade function and I know the increments required to calibrate the desired final hardness. I know what this steel looks like on the inside and how many foot pounds of sudden load it can handle.
Now it is up to me to shape that steel into a tool that is effective and pleasant to use. This is where Tai’s method and approach comes into play and will always be an integral part of my process as well. Once I have maximized the material itself, now it is up to my hands and “intuition” to make it into a knife that feels right, looks right and is a pleasure to use.
* The common argument of “what if your gauges are off, then you are screwed if you don’t know how to do it the old fashioned way” is a straw man! This only applies if you are fool that doesn’t use the methods correctly, or never learned heat treatment but had enough money to buy gadgets to do it for you. You keep and continually check the calibration of your equipment, you watch the HRC numbers and other tests results and the slightest deviation tells you something is up. You don’t just turn on the machines and walk out of the shop for the day for Pete’s sake. And to those who think that I need thermocouples as crutch because I can’t heat treat the old fashioned way…just try me. Or ask any of the folks who have been to my demos at Ashokan where all we have is a forge and a bucket of oil- if we are lucky. In fact now that I have worked with salts and have seen the exact color of 1500F I am even better with the forge and bucket.
On the other issue of KSA, I think they are an abomination spawned by an eagerness to appeal to the mall ninja types. I like specialization to do the task at hand very well, axes are axes and knives are knives, when you make a tool do too many more jobs than its original function it will do them all equally bad.
I have found an edge thickness and geometry that works very well for me (when I did the cutting competitions I always enjoyed comparing the edges in the final lineup) and I never used a flexing test to find it. The question was just re-asked about my testing. I have been asked in this thread about other tests I would use, but I was under the restriction of what tests I would use in the shop of the inquirer; under these limitations the rod thing doesn’t look so bad.
But this is my actual testing regimen:
I break the testing down into two categories- materials/processes and general practical application. The first consists of testing just the O1, L6 and 10XX I work with for its properties under the processes I have subjected it to. This consists of Rockwell hardness testing, Charpy impact testing, checking abrasion resistance and how the metal itself reacts to wear, and extensive metallographic analysis. From this I can fine tune my heat treating and forging methods to get the material alone to do what I want it to do, based upon precise and quantifiable data. The next step is practical application on the material after it is in the shape of a knife, this is for determining things like the best edge geometry, the type of edge put in, the weight and balance of the blade and any other functional aspects of the overall knife. For this the best thing to do is just use the damn knife and observe the results. But use it in a manner that resembles knife use.
The largest difference between this type of testing and the more down home approach is repeatability. If you can heat a blade to 1500F exactly and be able to hold it there indefinitely, then quench exactly the same way into the same medium again and again, and keep all of your previous treatments the same, you can then start confidently analyzing individual properties like this. To be honest the guy with a forge fire, a magnet and a bucket of oil needs to test whole lot more to insure quality control, probably every single blade should be tested to insure nothing has gone awry. If one slightest thing is off for him the only way to know is to test each blade. I know each O1/L6 blade will be 64.5HRC as-quenched and then will level off at 61.5HRC from an initial 30 minute temper of 420F. * My final long term tempers will be according to blade function and I know the increments required to calibrate the desired final hardness. I know what this steel looks like on the inside and how many foot pounds of sudden load it can handle.
Now it is up to me to shape that steel into a tool that is effective and pleasant to use. This is where Tai’s method and approach comes into play and will always be an integral part of my process as well. Once I have maximized the material itself, now it is up to my hands and “intuition” to make it into a knife that feels right, looks right and is a pleasure to use.
* The common argument of “what if your gauges are off, then you are screwed if you don’t know how to do it the old fashioned way” is a straw man! This only applies if you are fool that doesn’t use the methods correctly, or never learned heat treatment but had enough money to buy gadgets to do it for you. You keep and continually check the calibration of your equipment, you watch the HRC numbers and other tests results and the slightest deviation tells you something is up. You don’t just turn on the machines and walk out of the shop for the day for Pete’s sake. And to those who think that I need thermocouples as crutch because I can’t heat treat the old fashioned way…just try me. Or ask any of the folks who have been to my demos at Ashokan where all we have is a forge and a bucket of oil- if we are lucky. In fact now that I have worked with salts and have seen the exact color of 1500F I am even better with the forge and bucket.
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A broad side of a barn comes to mind.