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paulddraper

IDK if 2.40625 + 5.6875 is any easier :)

Inches using base 2 for the fractions is useful.

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> Inches using base 2 for the fractions is useful.

Why? You can't just say that without a reason.

(The numbers you cited above don't count, because you'd instead use 6.1 and 14.4 (or maybe 14.45) centimeters)

Certainly.

Let's say you are centering a 2 1/4" board on a 22" frame.

The edges need to be 8 3/8" apart.

It's a lot more common to divide lengths in halves (and quarters, etc) than tenths.

But say you have to divide a 8 3/8” board into 5 parts. That turns into an ugly 771/40. What do you even do with that using an imperial measuring tape?

I have never needed to divide a board into 5 parts.

But if I did that would indeed be difficult.

I regularly need to divide to build bookshelves out of 4x8 plywood sheets.

Are you visually or mentally impaired? I don't mean it in any condescending way. I can add those on the spot by just looking at the numbers and tell you result immediately, that's primary school level math in Europe.

Yes I'm mentally impaired.

That's why I like to do things that are easier.

2405.25 + 5687.5 is easily 8092.75. But in both cases not using a calculator and not doing an operation on it at least twice (if it has no log) is a recipe for wtf, imo. An expensive mistake requires only one miscalculation.

It isn't easier, but 6.112cm + 14.446cm is fairly easy. Especially if you drop thousandths, which you can only maybe get when measuring with a caliper...

Inches only use base-2 fractions down to 1/64", then they switch to thousandths of an inch (thou), with base-10.

Easier to type into any general purpose calculator. It’s also so much more accurate when trying to enter into any CAD/CAM software.

It’s also easier to add up 10 different decimal numbers than the same number of mixed numbers.

Yeah, I don’t think woodworking is the best example for arguing that metric is better than imperial. In fact, it’s one of the few disciplines where the imperial system as a decent argument for superiority.

Metric woodworking just uses integer millimeters for everything.

Woodworking measurement has two forms: lumber, which is notional, pre drying, shrinkage and rough handling, and cut, which is required to be beautiful. Sometimes, it isn't about feet and inches as much as "the same"

Plumbing is another example where imperial works and is even used in Europe. It doesn't matter that a pipe is 3", it may as well be called "type B", since all you care about is if it's big enough for the purpose (you look that up in building code) and if the parts match together. The moment you need to perform calculations is when imperial becomes a total PITA to use.

Minimum radius is much more important in plumbing I think than metric/Imperial. And screw-thread.

WDYM by minimum radius? Are you referring to the part of my post where I wrote that you just look it up in the building code (as opposed to trying to calculate it), or when actually designing where the pipe runs?

The intersection of both. I did a very bad job of plumbing an electric shower into my flat in York back in the 80s and working out how to route the pipe to meet both ends requirement of where I could connect it into supply, and where it had to be to deliver water to the heater, was massively confusing. I am sure a plumber would understand this innately, but I wasted 2+ m of copper pipe trying to "route" it, without understanding the limits of how I could bend it, or cut and use a fitting.

The building code(s) only get you so far. There's also aesthetics.

Ah, well, I only did PEX and ABS for my reno, very idiot-proof so I managed. ; )

I made the mistake of watching (as a kid) a plumber use his own body to form the curves, and assumed "it's that easy" without taking in that he was 25 years past his apprenticeship and had bent thousands of pipes, and used a former almost all the time. It's a different game when its you, the pipe, and twenty needle-jets of water streaming out of the badly fitted olives, lack of PTFE (or too much) tools which don't fit, pipe with ugly crinkles in them, splits along the length...

Sorry, I dabble with woodworking and disagree heavily. I usually don't care for bigger precision than 1mm (so between 1/16" and 1/32"), and adding things up is a nightmare ("umm... 7 3/16" + 2 1/8" + 5 1/4" is... where's a goddamn pen & paper..."). Same with figuring out which line is which fraction of an inch on measuring tools. Things became tolerable once I got metric measuring tape.

Once you get past the dabbling stage it starts to get pretty natural. I don't think either system is better, the value is mostly tied up with what's on the shelves at the local home center and how your measuring tools are marked.

The stuff on the shelves is rarely sized precisely enough for the units to matter. I've bought 1/4" ply that measured much closer to 6.0 mm than to 1/4".

It's already natural when using metric, so I'll stick to it.

Sure, if tools are dirt cheap you can just sacrifice to Benford's Law and use base 10. If tools are not cheap, you'll learn to use base 2, one way or another.

I doubt I'll ever be able to quickly add fractions in base-2 (it doesn't happen often enough to train this), so pen+paper will always be a necessity if I wanted to stick to imperial. I could see getting the intuition for "which line is the eights vs sixteenths" over time though, but if the one-off calculations are going to be such a pain, I don't really see a point.

My FIL is a fine art woodworker (makes stupidly nice furniture, canoes that are functional art, etc.), and he uses both. He’s done it so long that he can work with fractions instantly in his head, but he also fully admits that metric is way easier for a lot of it, and so uses both as needed.

About the only example of imperial being easier I can think of is that the thin-kerf saw blades he buys are American, and thus are measured in inches - 1/16” to be precise. It’d be tremendously annoying to deal with 1.588 mm. If he had a 1.5 mm blade, of course, it would be the other way around.

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