Friday, July 8, 2016

Rockwell Rating

Today two customers came into the showroom asking about the knives and hardness. The knifemaker's lady friend ran through the spiel about the source of metal, carbon percentages, blah, blah, blah to which the customers said "But what is the Rockwell Rating?"

What to say? What is this person talking about?  Even the knifemaker's lady friend hadn't come across this to date.


The knifemaker's aunt zipped into the shop for reinforcement. The knifemaker's dad came into the showroom and answered all the questions. Know what the Rockwell Rating is? It turns out the Rockwell Rating is a system of measuring relative hardness of items based on the depth of an indentation an heavy object makes when dropped onto the thing being measured. The actual rating he difference between the indentation a ball makes on an object upon impact and the indentation it makes again after a period of time. [There's more of course, but as a base piece of knowledge it works.] There is a bunch of math involved with the system, which made the knifemaker's aunt go Yikes! 

This is algebra in motion for everyday work! Now she has a valuable reason for why those middle school kiddos need to learn how to calculate differences. Good lesson to learn! Basically, the Rockwell Rating is the difference 

Wow, Rockwell.