Size matters, Andrew
adam Cherubini, NJ
>Take it from a yank.
Let's start by cleaning up your history a little. Blacksmiths didn't make woodworking tools generally. Edge tools were made by Cutlers, men who made nothing but blades. And they generally "mass produced" tools, starting from the time in which England became industrialized (after the Fire of London). Before that time, fine furniture was rarer and difficult to build. The styles were technically cruder to my eyes. Dovetailed cases for example, were not common (or existant).
It would be likely that all of most of one's tools came, if not from a single Cutler, than from a single town- like London or Paris or Sheffield or Solingen. So the variability of absolute units wasn't an issue.
But you are correct that 18th c tools varied in sizes. Because my personal tools came from a variety of regions and times, I'm a bit worse off- my tools being less reflective of earlier kits. So I "corrected" my plow irons to perfectly match my mortisers for example.
And actually, as Derek mentioned, this was my idea that lead to my post here. That the dubbed edges issue, raised a while ago by David Charlesworth, might be solved by dressing down the edges instead of doing all that back flattening and that the edge work might also "correct" the widths to more useful sizes. Since I've done this work before, I was comfortable withthis recommendation. There is very much less material to remove on the edges than on the back.
Now to the meat of your comment: You're right, if all my tools were metric I'd be better off. But one problem I'd still face would be that I'd be missing a chisel equal to or a little greater than 1/3 my standard stock thickness. 6mm to 10mm is a pretty big jump in a range of sizes oft used. So its not just the tools matching, but the tools matching the stock and the structural requirements of joints in that stock.
Just for comparison sake, 18th c mortisers were available from 1/8"-1/2" or 5/8" in 1/16" increments. Firmers were availkable in at most 1/8" increments. So there were plenty of tools in the small sizes. So I guess to make me happy, I'd want Hirsch to make 5, 7 ,9 and 13mm chisels. Make sense?
Adam