John, you always have known that I think you are pretty sharp, but I have to warn you that you are playing with fire with this one, although I am firmly in your corner. I have found that you can tell a smith he is full of @##$ in just about any area but this one and still be friends. I have been able to get folks to listen to a whole lot of points just by pointing out facts and logic, but the one thing that has made more enemies for me in this business is to have the nerve to ask "why were
quench oilsdeveloped" or that perhaps a product called "quench oil" just may be the one best suited for quenching
.
I must admit that I really enjoy this forum these days because here is one of the few places one may be able to address this topic without getting flamed to a crisp. Here I have seen many folks who have actually at least tried actual quenching oils and were pleasantly surprised to find that they work really well for
quenching.
The problem is that too many of the writings that folks go to for information includes recipes for all kinds of eclectic home made quenches, and trying to overcome this is tough, after all Mr. X wrote it and Mr. X is published so he must know what the is talking about.
If there is one part of this whole game that
is an exact science, it is the heat treatment. There isn't a knifemaker alive that could argue that heat treating is the soul of the knife, so to me this is the one place where we should cut no corners, "good enough" should never be reachable in heat treating. I do not approach this from an industrial standpoint as mete has the advantage of, I approach this from a lifetime of bladesmithing. enough time to look much deeper than skating a file, cutting rope or bending blades.
I write this through blood shot eyes that were up late last night looking through that damned microscope again. And once again my whole world view got rearranged on heat treatment. I now have to reconsider my pre-heat treatments, soak times and tempering schedules (and this is on blades that are performing better than any previous ones). But I do not have to reconsider my quenchants. They have allowed me to get consistent results for many years, consistent enough to allow to do all of my more accurate analysis and testing.
This is the way I put it to those who immediatley assume I am knocking their blades when I ask "why were quenching oils debveloped"- you can successfuly pound a nail with a rock or a pipe wrench, but they do make hammers, and if you plan on driving nails for a living wouldn't a hammer be a wise investment.
I used to feel guilty that I may come off as anti-alternative quenchant, until I saw how violently anti-proper quenchant so many folks are. I have seen all of the arguments for not using this wonderful tool (too expensive, too hard to get, uncessesarry, too messy, too stinky etc...), I have checked them all out and found almost universally the opposite. I am having a lot of fun with my satirical articles on my web page, but the one that I had almost finished and then shelved it dealt with thic topic, I realized that I just wasn't prepared to be that unpopular yet.
One thing that we all need to remember when considering this, and we do tend to forget it often, we don't charge loyal customers $1000 a pop for making tea, pencils, bread, umbrellas etc...
I can't speak for knives in gerneral but I can most certainly say that the quality of my knives, and more improtantly my life, has greatly improved with the introduction of quench oil.
I used vegtable oil many years ago with good results but the real stuff work much better.
. My favorite is Parks AAA for O1 but Parks products does indeed fall into that category of hard to get, but there are plenty of other oils readily available on the market. 
. No cracking at all (which would have been a sure thing had the pieces been 1/2" or thicker), so one may get away with faster oils in the thin cross sections knifemakers work with, but distortion would probably be an issue.
