06-25-2018, 03:54 PM
Just a little update. We are about half way through the testing process with our A2 samples. One interesting piece of information that has already popped out was our ability to pre-sharpen and then heat treat A2 steel samples. For what it's worth to bladesmiths and knife makers this seems to be a viable option with, at least, A2 steels.
It does not appear that one needs to do a particularly complete job of deburring edges prior to heat treat. That's good news because deburring non-hardened steels is a real pain. Edges that tested 350-450 prior to heat treat due to inadequate deburring could be easily finished up post heat treat into the sub 200 range. Edges that were tempered at temperatures that yielded higher HRC numbers seemed to deburr more quickly and yield better final sharpness numbers in general but it's still too early to say so categorically. It may be true that deburring prior to heat treat may not be necessary at all and that question will be answered because we made provision to test for that element with this set of samples.
We are leaning toward releasing the bulk of this report in two jags; first the pre-sharpened edges and then another round of those same edges but post sharpened.
On another matter, here's a picture of a pre-sharpened and post heat treated edge (It's our #11 that measured 180 BESS at the point in our picture);
Do you scratch mark experts see anything unusual here that may have resulted from heat treating the edge after sharpening? The edge was ground with a 180 grit ceramic and then a Sharp Pad for burr removal and that's it. We hesitate to share our microscopic photography and sharpening numbers publicly like this because it makes Grepper (microscopy) and KG (sharpening) jealous but perhaps this post will slip by their notice.
Doesn't feel to the thumb nor appear to the eye from the picture that there is much tooth left here and that may be one interesting result of the post heat treat process.
It does not appear that one needs to do a particularly complete job of deburring edges prior to heat treat. That's good news because deburring non-hardened steels is a real pain. Edges that tested 350-450 prior to heat treat due to inadequate deburring could be easily finished up post heat treat into the sub 200 range. Edges that were tempered at temperatures that yielded higher HRC numbers seemed to deburr more quickly and yield better final sharpness numbers in general but it's still too early to say so categorically. It may be true that deburring prior to heat treat may not be necessary at all and that question will be answered because we made provision to test for that element with this set of samples.
We are leaning toward releasing the bulk of this report in two jags; first the pre-sharpened edges and then another round of those same edges but post sharpened.
On another matter, here's a picture of a pre-sharpened and post heat treated edge (It's our #11 that measured 180 BESS at the point in our picture);
Do you scratch mark experts see anything unusual here that may have resulted from heat treating the edge after sharpening? The edge was ground with a 180 grit ceramic and then a Sharp Pad for burr removal and that's it. We hesitate to share our microscopic photography and sharpening numbers publicly like this because it makes Grepper (microscopy) and KG (sharpening) jealous but perhaps this post will slip by their notice.
Doesn't feel to the thumb nor appear to the eye from the picture that there is much tooth left here and that may be one interesting result of the post heat treat process.