(12-31-2016, 05:23 PM)Mike Brady Wrote: I found the "machining' process described to be quite informative.  I don't believe what is described would be termed as machining (surface grinding) today.  Back then they had a process known as "linishing", which is kind of a more robust belt sander that we use today.  When I look at the couple of NOS planes I have from Stanley, they look like they have been sanded, as opposed to ground.  The marks are not consistent with a precision truing of a surface and look as if the casting might have be held by hand during the process.  Either I am close to correct on this or the castings distorted with age, because most planes are far from flat and true when found today.  It's hard to believe that wear causes this, particularly when the rest of the tool shows no signs of wear.