I don't know if I would call it "missing the boat". I think it's a matter of time and experience. By that I mean...I worked for about 15 years without any means of actually knowing the temps inside my forges..doing it all "by eye". As I became hungry for answers as to why certain things were, or were not happening for me in relationship to forging temps, I chose to put a pyrometers on my forges. The first one I purchase was a complete unit with a digital readout and thermocouple that I purchased from a pottery supply outfit......and it was SPENDY. With help from folks who knew more about electronics than I do, I learned that one of the PID controllers and a type K thermocouple makes a very economical and effective pyrometer.
After installing pyrometers in all my forges, and learning to pay attention to them as I worked, I was quickly able to relate that certain things occur with the steels at specific temps and durations....which only made things easier for me, and gave me new insights.
The magnet is a good tool, but in reality, most steels will go non-magnetic aprrox. 150F or so BELOW critical temp. Where that really becomes important is that you have to realize that in order for steels to fully harden, they must be at critical temp when they hit the quench....not when the steel is 3-4 ft. away from the quench tank. If that situation occurs, then by the time you're at the quench with the steel, you've lost a couple hundred degrees. All kinds of outside factors come into play.....what's the ambient temp in your shop at the time? Are there any drafts or breezes? How far away from the heat source is the quench tank? All too often I get calls or emails from individuals who don't understand or realize why they are not getting full hardening on their blades...I've learned to have them walk me through their process in a very detailed manner. You'd be surprised at how often their problems boil down to the steel not being at critical temp when they hit the quench. Everything from trying to harden outdoors with the wind blowing, to having to walk a dozen steps to the quench tank (and by then they are WAY below the heat required.)
Back to the issue of a pyrometer....Do I think it's a necessity? No. But I do think that once an individual's knowledge level reaches a certain point, there's no better way to acquire answers you seek, than using one.
Without the pyrometer I might not have ever been able to successfully weld 416/San Mai billets. I failed several times because I did not know the correct temp to soak the billet(s). With the pyrometer, it took me far less attempts before I discovered the correct temp, and now I know exactly what the temps have to be to get it right. So, although it was a long time coming for me, having a pyrometer on my forge has certainly helped me be "better" at what I do.
