I have worked in Inches for so long it's just easier for me, but could work metric if needed. For woodworking I will stick with inches until I find a real advantage to metric. They are all just numbers in the end.
I have worked in Inches for so long it's just easier for me, but could work metric if needed. For woodworking I will stick with inches until I find a real advantage to metric. They are all just numbers in the end.
As I've noted in other thread, I've switched to metric for CNC work, but use Imperial for all hand work --- esp. if it involves dividing by thirds / sixths / twelfths, &c. If need be, I break out a desktop publishing points ruler to get 72 points per inch which pretty much always guarantees that distances will be some nice even number as opposed to the irrational values which dividing into thirds using metric usually results in.
As I may (well, certainly) have mentioned some time back, the country that put men on the moon did not do it alone. That county's eyes and ears for half the time were on the other side of the globe. So please don't trot out irrelevant excuses.
More to the point, use whatever system you want. Australia changed systems as a nation when I was in school. We all got over the shock, and the sky didn't fall on our heads. I learnt both systems and understand both systems but use metric because that is the official system. It's like I speak English because that is our official language but it doesn't stop me understanding Polish (especially the curses....!).
I believe the key to the change in Australia was that there was clear leadership with the issue. Also, Australia adopted units in multiples of 1000 ie microns, millimetres, metres and kilometres. Centimetres are not official and never appear on technical drawings. That way everything has up to 3 decimal places for each unit. If you want to go smaller than microns, be my guest.
We have an extensive range of CNC machining centres here. Most of our operators are in the 55-70 age bracket. They all learnt machining in imperial and much prefer working in metric.
I do recall my boss back in about '74 commenting how measurement errors dropped markedly when metric was introduced. That was in residential construction.Cheers
Every construction obeys the laws of physics. Whether we like or understand the result is of no interest to the universe.
I work with Russian plywood all the time and it's definitely metric. 18 mmish by 1220 mm by 2440 mm. Says so right on the label. Now grab your calculator and see if it's the supplier or the consumer that's determining the size of the "metric" plywood.
I've run into all kinds of stuff in construction that's "metric" but when you convert you find that it's based on an imperial standard. Not just construction either. If you know anything about firearms you've heard of the AK47 round which is 7.62x39. That's a bullet diameter of 7.62 mm. Guess what that converts to. 0.300", which is "30 caliber".
Since base 10 is so much better when are we all going to change our method of telling time?
For woodworking measurements, which are almost all about length, I am pretty indifferent - either works equally well for me. Sometime the binary fractions are handier, sometimes the decimal. If, for example, I am working a Golden Ratio in a design, or need to subdivide a length by anything that isn't a power of 2, I use metric for ease of calculation. For most woodworking measurements, though, decimal has no particular advantage. As a result, I sometimes use both on the same project. For everything else, the SI measurements make so much more sense because of the overall logic of how the different measurements relate. I of course use the Imperial measurements for volume and weight to buy food and gasoline, because that's how stuff is packaged and sold for the most part. But I'd prefer metric, and I do everything involving any physics more complicated than volume in SI.
I agree it does not matter which system but choose one for the job and stick to it. The problems start with "what's metric for 15/32?"
I recently did a construction job (about a year worth of work) that had metric plans. The only place we really measured in metric was for the block walls. 40cm per course, couldn't do the conversion on my head for more than one course. Then we switched over immediately to a job with imperial measurements on the plan. I'm not going to lie, it took some focus to mentally switch gears.
When doing cabinets, I use metric almost exclusively. Decimal inches are a close second, but I've given up on fractions for anything where I need to add and subtract a bunch of numbers (overlays, reveals, etc.). Too much time and too many errors.
I do find mm a little easier and little more intuitive than decimal inches. Maybe because it's a completely different system whereas with inches I keep reverting to trying to think in terms of fractions.
For furniture, I'll use either system. Sometimes it's inches for the conceptual stuff and then mm and story sticks when it comes time to build, or sometimes all inches.
My $19.99 Harbor Freight Imperial/metric/decimal/fractional caliper makes switching back and forth just a simple matter of touching a button ......plus...it measures things too!
"Life is what happens to you while you're busy making other plans." - John Lennon
I use both systems, and often use them alongside one another ... that can be confusing for some who read my notes!
Metric is definitely easier when one has to add together what otherwise would involve fractions. For example, 2.5mm + 2.75mm vs 2 1/2" + 2 3/4".
Metric is easier when working from my European machines, especially the thicknesser (planer), which is Metric. It does not make any difference with the Festool Domino machine, since an exact position (in numbers) is not important.
Imperial raises its head because I must allow for the fact that all my hand tool joinery planes and chisel blades are in Imperial (e.g. plough plane, router plane, mortice chisels, dado plane).
Also, it is easier to visualise 6 feet than 1828.8mm or 1.828m!
My tape measures contain both sets of numbers.
Much of the time tape measures are for rough work anyway. Most of my measuring is done with a cutting gauge or from parts.
Regards from Perth
Derek