In the old days

I hope this is in the right spot, if not please move it. In the old days they knew a thing or two about centering a blade in a set of scales. Decided to clean up an old pre 1891 Joseph Rodgers a little better and discovered that it had only one washer at the pivot. I thought that was strange until it dawned on me that I needed to hone it with a rolling X stroke. Same method for centering a blade with a bent spine as recommended and used today in this forum. Everything old is new again or some things never change. First time I had seen it on an oldie.

Bob