Imperial or metric?

[Steve Voigt]

I use Imperial, but convert everything to the closest thousandth of an inch. Most of my tape measures are Imperial. I usually buy rulers with a scale for 10ths, 100ths on one side and 1/16ths, 1/64ths on the other side. Imperial calipers read in thousandths.

So in effect, I am using Imperial in a metric fashion. I would have preferred to make the switch to metric in the 70s.

Steve

I do the exact same thing. I bet you are a machinist. I used to be one, and thousandths are permanently imprinted on my brain. Intellectually I can certainly agree that the metric system has advantages, but I think in Imperial and that's not going to change.

[Steve Voigt]

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.

[Derek Cohen]

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.

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

[Steve Voigt]

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.

It obviously depends on what you're doing…if you're just roughing out a slot that will be pared with a chisel, one's as good as the other.

[lowell holmes]

This thread in interesting in that it's had some staying power.

I just use whatever is convient. Matching is important, for instance I have a 6mm mortise chisel that actually measures .250" and so I use it in conjunction with my .250" grooving plane.

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.

[Brian Holcombe]

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".