Last edited by Steve Voigt; 12-06-2015 at 11:52 PM.
"For me, chairs and chairmaking are a means to an end. My real goal is to spend my days in a quiet, dustless shop doing hand work on an object that is beautiful, useful and fun to make." --Peter Galbert
Jim K. and Brian raise a good point, which is that there are benefits to being conversant in both systems, even if you prefer one. I just bought some 5 mm end mills today because they were the closest thing to the ideal size, and the price was better than 3/16ths. And like Jim, I've used metric sockets forever, because my first 2 cars (and first 4 engines ) were Volkwagens. I never had to buy a whole set of SAE sockets--just filled in the missing gaps in my metric set.
"For me, chairs and chairmaking are a means to an end. My real goal is to spend my days in a quiet, dustless shop doing hand work on an object that is beautiful, useful and fun to make." --Peter Galbert
I mentioned early in this thread that I use both systems, often at the same time. Sometimes it is forced upon me - my Hammer jointer/thickernesser-planer uses metric, and all the screws/bolts available are imperial (this is in metric country).
I would not replace 5mm with 3/16" since 3/16" is 4.75mm. I have been making drawer slips and grooving with a plough with a 3/16" iron. This has to run into the front groove (behind the drawer front). The drawer front is bowed and I cannot use the plough plane. If I use a router, it needs a 3/16" and not a 5mm bit otherwise the grooves will not match.
I have restored cars for many years and the socket set I have is interchangeable between metric and imperial.
Regards from Perth
Derek
"For me, chairs and chairmaking are a means to an end. My real goal is to spend my days in a quiet, dustless shop doing hand work on an object that is beautiful, useful and fun to make." --Peter Galbert
My first set of good chisels was a four chisel Marples Blue Chips from Lowes. I learned to match the metric chisels to the nearest imperial widths. I tired of that and started buying antique Stanley chisels. I started getting some good chisels and some inferior chisels as far as metallurgy was concerned.
That's when I bought some Lie Nielsen chisels. They are good in every way, fit,finish, accuracy, and sharpness.
At the risk of being pulled into this thread It has not been an issue for me, in Cases such as through tenons I appreciate the room, it allows me to pare the sides.
So there are benefits to both sides of things, but in the places where I need a match, I have them predetermined. In the case mentioned with the '6mm' mortise chisel, it arrived at something like .260" and I ground it down to .250".
Bumbling forward into the unknown.