Thread: The Great Razor Analysis Project

Originally Posted by Slant-Fan

I have wondered about the temper and content of various razors myself. In the book Hatcher's Notebook a longtime ordinance officer General Julian Hatcher compiled notes on his observations made over the years. Among the topics was the heat treating of '03 Springfields. Some of them below serial # 800,000 were prone to failure and had in some cases caused serious injury to the shooter.

It was found that the workers responsible for the heat treatment relied on the color of the metal as it was being heated and cooled to determine when the correct temper had been reached. After further analysis it was found that depending on whether it was a sunny or an overcast day the temperatures of the metal being heat treated could vary up to 300 degrees using the eyeball method. Afterwards the Armory began using pyrometers and the problem was solved.

I bring this up because I am assuming that the razorsmiths in the 1800s probably tempered by eye so the results will probably vary whereas once pyrometers were introduced tempering would have been more consistent.

This is a great point. I hadn't even thought about how companies judged the heat treating temperature. I do know from personal experience that even 100 degrees or so makes a huge difference. My forge has a hot spot in it that's not an issue for razors but does make it difficult to evenly heat blades longer than 3 inches or so. I've found that overheating part of the blade by even 100 degrees means it doesn't get as hard.

Trying to judge 100 degrees by eye would be very difficult. I have a hard time judging temperature by color, and I have a dark garage to work in. I can only imagine how the temperature would vary with different lighting conditions, not to mention multiple workers doing the eyeballing... Wow. Does anyone know when pyrometers were invented?

Edit: I'm seeing references to pyrometers as far back as 1775, so they probably were using them to treat razors. But I'm sure they varied in their accuracy.

Josh