The way Gramps sharpened his plane irons
Seventy-five years ago most handtool woodworkers were professional carpenters, joiners, millwrights and millmen. They depended on their tools to make a living. They were paid on the basis of their productivity. They knew how to sharpen their tools to maximize their productivity and they knew how to do it fast.
Now, most handtool afficinados are very dedicated amateurs (or recognized artisans with clienteles that are willing to pay for “toolmarks”). This group of handtool users has the luxury of time, time to fettle their tools “in absurdia”.
Matt Sullenbrand, frequent visitor to this site and provider of wise observation, sent this recent comment;
“I have purchased lots of old planes over the years, and started out flattening the backs on all of them. Then I realized, if none of the craftsman who owned these planes worried about flat backs, why should I? I am not convinced that flat backs on plane irons were ever necessary. It seems more likely and more expedient that it was the norm to use a back bevel on almost all irons, save maybe profiled plane irons which would have been very difficult to back bevel. Just a thought.”
After reading Matt’s comments, I began to think about how my Grandfather taught me to sharpen a plane iron. First, you have to remember that not all planes are used for “polishing”. Most, are used for sizing and truing. So, fifty-four years ago, Gramps taught me to sharpen plane irons like this.
First, make sure that the iron is ground to the purpose it was intended. Here’s a number 6 iron that’s ground with a substantial crown. Remember that a 6 is a foreplane. It’s the plane that “strikes” the first datum or register, from which all other dimensions are taken. So we get the “grind” right:
Then we “run” the iron in a “figure eight” motion on a hard arkansas stone. Just as soon as we raise a “wire”, we strike it off by moving the iron laterally, while just raising the heel of the iron “ever so slightly” off the hone.
Then we move to a hard black arkansas stone. We repeat the same “figure eight” motion, raise the wire, and, again, strike it away. We don’t go to the strop. The iron is razor sharp at this point. The honed, secondary bevel in very small, which means we’re not wasting valuable tool steel.
We reassemble the iron and the chipbreaker and begin to work. I mean, how many angels can sit on the head of a pin?