I feel like I've been missing out on something (thanks, Festool!)

[Jon Endres]

Not necessarily the tools, I still can't afford most of them, but the metric system. I bought a Domino DF700 XL a year ago and I simply cannot wrap my head around SAE measurements when dealing with Domino tenons and getting the right depth, thickness and spacing correct. I picked up a cheap Starrett metric tape measure and all of a sudden my accuracy on everything is improving. It's so much easier to do the math, no matter how your project is laid out. 1/2 mm is easy to read on a tape and that gives me nearly 1/64" accuracy. I feel like I should be doing everything in metric, at least for cabinetry and furniture. Even for non-Domino stuff I find myself reaching for the metric tape more often than not. Any of you American woodworkers switched over to metric in your woodworking shops?

[Mike Henderson]

I go back and forth. I have a fill set of metric measuring tools and sometimes I do metric and sometimes Imperial. I agree that metric is easier to work with.

Mike

[ChrisA Edwards]

My 2020 New Years resolution was to go Metric. I swapped out my Tablesaw rulers and my J/P depth gauge and bought some new hand measuring tools.

Never going back.

I printed out a cheat sheet of conversion of inches to mm. I still struggle to guesstimate distance, say like 28" in mm. That's where I go to the chart.

[Michael Fink]

Metric makes so much more sense. Most people can't work easily in fractions; I can do it, but it takes some thinking, particularly if we're trying to add really precise measurements together. Metric would make my life a lot easier, no question. Problem is, like I'm sure many others, I have a whole shop of tools in imperial measurements. Planer, sander, table saw, band saw, miter station. The list goes on. And, IDK, about 100 measuring devices of various types that are all in/ft. Of course I could do it, but I'd have to spend a lot of money and throw away a bunch of tools to make the transition.

No denying, at least in my mind, it's a better system. But the "sunk cost" for me is too high.

[Jon Endres]

My 2020 New Years resolution was to go Metric. I swapped out my Tablesaw rulers and my J/P depth gauge and bought some new hand measuring tools.

Never going back.

I printed out a cheat sheet of conversion of inches to mm. I still struggle to guesstimate distance, say like 28" in mm. That's where I go to the chart.

I figured that one out quickly - "Alexa, convert 28 inches to metric".

[Dave Roock]

When I was in elementary school, we were forced to learn the metric system because the USA was going to switch over to use it - since the rest of the planet used the metric system, it sure made sense to a child. But the huge corporations who run/own some of our politicians with lobbyists, blocked a switchover because they did not want to pay to switch equipment over. Absolutely ridiculous we are still using pounds, feet, inches - if you travel to any other nations, you will be at a disadvantage as everything is in metric measurements. Would not be very hard to use our imperial tools for metric measurements - planers, jointers, table saws, band saws, etc could all be used with no difficulties.

[mike stenson]

I prefer not to measure, but when I do.. it's typically metric.

[John TenEyck]

I spent most of my engineering career working with metric including designing all kinds of machines and fixtures, but I just can't think spatially very well in metric, so I continue to use imperial units for my woodworking. Most tools and parts sold in the US are imperial based, too, so there's that inertia. And when I talk to a customer we always talk in feet and inches; they would look at me like a deer in the headlights if I tried talking metric.

I agree that the math is much simpler in metric, however.

John

[ChrisA Edwards]

I figured that one out quickly - "Alexa, convert 28 inches to metric".

Ha, just tried that, Alexa replied "About 711 mm"

Siri said "711.2 m".

[Justin Pfenning]

John TenEyck, I agree 100%.

[George Yetka]

https://www.senecawoodworking.com/products/imperial-thickness-gauge-domishim-for-festool-domino-xl-df700

This will help keep it to one system for you. That being said it is appealing going to the other side but it would cost quite a bit to swap.

[Ralph Okonieski]

In the last 2years, my approach has been switching to metric units. As John mentioned, I also have not been able to easily think spatially in metric. I tend to measure twice, first in metric, then inches followed by a conversion on the calculator just to confirm. Yes, a little OCD but a process with which I am comfortable.

[Prashun Patel]

Metric is so much better in every way.

I still use imperial…. Just unfortunately more intuitive for me.

[Bill Cuthbertson]

i tend to use metric when dealing with European hardware, would like to go all metric but just not willing to take the plunge.

I am not a professional cabinet maker any longer but every tradesman, coworker, contractor etc... I talk to deals in feet inches, makes the witch difficult.

[Frank Pratt]

Even though I live in Canada, I've only recently switched to metric in the shop. It hasn't changed my life, but it's made it easier and I make fewer mistakes.

[Allan Dozier]

With me it's like exercise. I make a resolution and use it then find myself slipping back into old habits without thinking.

[Carl Beckett]

I still think in miles for longer distances.
Then yards. Unless its track and field (or swimming) which are now all meters so the times are calibrated to those distances. Although american football are yards.
Then feet.
Then a combination of inches and mm. Cm is off for me. Although chemistry I do in liters and mL, cooking is done in oz.
Once I get below an inch about 10mm and less is almost always mm
If machining, its inches when dealing with 'thousands' (most machine shop equipment is still in inches)
Going below this is almost all metric. Microns. Sub micron in the nanoparticle is all nanometers. Down to angstroms. I dont work much below about 100nm

So.... its a mess. The mm range is pretty nice though, even increments that in that size range are nice uniform numbers with decent resolution.

[Derek Cohen]

Until I was 10 years, we had Imperial measurements and £ shillings and pence. Thereafter all was Metric. I was reasonably comfortable using both, but a few items, such as height and weight, were easier in Imperial.

It was not until I purchased a Hammer A3-31 that Metric in the workshop became the default. The A3-31 is Metric, and all flows from the thicknesses one is using.

Regards from Perth

Derek

[Jared Sankovich]

I just convert everything (fractions and metric measurements)to decimal inches in my head.

[Rich Engelhardt]

I just convert everything (fractions and metric measurements)to decimal inches in my head.I cheat and use a fractional digital caliper.

[Brian Holcombe]

Much prefer SAE.

[George Yetka]

476016
Came across this and thought it applies

[mike stenson]

Until I was 10 years, we had Imperial measurements and £ shillings and pence. Thereafter all was Metric. I was reasonably comfortable using both, but a few items, such as height and weight, were easier in Imperial.

It was not until I purchased a Hammer A3-31 that Metric in the workshop became the default. The A3-31 is Metric, and all flows from the thicknesses one is using.

Regards from Perth

Derek

Old money? That makes my head hurt.

[Jim Dwight]

I also prefer SAE. I also do not think that there is a better and worse when we're talking about systems of measurement. They are arbitrary. Just a way to define things. But I do not understand metric like I understand SAE. The barrel of my favorite air rifle is 450 mm long. But I have no understanding of that until I convert 450mm to 18 inches. I know an inch is 25.4 mm. I know a kilogram is 2.2 lbs. But if you tell me your height in mm or cm, I will not understand it until I convert it. If you tell me your weight in kilograms, I also need to convert it to understand what you said. It is not that SAE is better (or worse), I understand one, I have to convert the other to it to understand it.

I also have a domino XL and I use metric when I am using it. Some of my steel rulers have metric scales and that helps. But the project is done in feet and inches and fractional inches. Always been the way I work and always going to be. No real reason to change.

[mike stenson]

It is, IMO, not much different than speaking in multiple languages. You either think in the language you're speaking in, or you're translating. The difference, is generally the amount of usage. I grew up with metric, and the US is obviously imperial... so I can think in both.

[Jim Becker]

I largely switched to metric for my own builds a few years ago and prefer it. I only do inches for home improvement tasks because that's how a lot of materials are focused. I've found it a lot easier to work with metric than with fractional inches or inch-decimal for the kinds of things I like to make. All my measuring tools and machinery support both systems so I'm good to go for whatever task I'm doing. The single most important thing is to try to not mix systems in the same projects outside of fasteners where you need to choose what is available to you.

There have been a number of "passionate" discussions about this here at SMC over the years. There are folks who love metric and there are folks who are "over my dead body". It's just a measuring system. Use what you prefer.

[Frank Pratt]

I bet I could really stir this pot with just a couple of sentences :) I'll refrain.

[al ladd]

CNC made me convert to decimal inches. Easy enough in the CAD program, and easy enough on a digital caliper. For finding those weird decimal inch CAD dimensions on a ruler I've discovered 16R graduations, and have several 6-24" steel rulers in that system. 32nd and 64th on one side, and 100ths and 50ths on the other. 100's aren't friendly to my eyesight, but the 50th's scale is really useful for locating things like .86". Working in decimal inches is sort of a hybrid between metric and inches.

[Bill Dufour]

I became a semi convert when I installed fog lights and different seats in my Datsun. First I tired to make sense of bolt spacing in English units. Once I switched to mm It was easy to center things up. Turns out there are only two Japanese car seat makers so most stuff above the mounts can interchange regardless of brand.
Bill D

[Alan Lightstone]

I try to use metric as much as I can, and have almost all my measuring equipment set to readout in Metric.

The math is so much simpler.

But, even after a career in medicine, metric weights make perfect intuitive sense to me, but metric heights scramble my brain. Probably because metric height was largely irrelevant to drug dosages, but weight/mass was extremely important.

I used to talk to one of my Irish surgeons about how many stone his patient weighed. He instantly knew the meaning.

[Rod Sheridan]

I went metric in woodworking a couple decades ago, one of my better decisions.

I just treated myself to a new metric Starrett machinist square, really nice…..Reqards, Rod

[Grant Wilkinson]

Canada "went metric" many years ago, but not really. Officially, we measure air temp in celsius and baloney in grams. However, we also by 2 x 4's (which really aren't 2" x 4", of course), we buy sheet goods in 4 x 8 sheets and the car tires for our 18" wheels. Rough sawn lumber is still 6/4 and 8/4, but baltic birch plywood is 6mm and 18mm. MDF is sold as 3/4", but really isn't. It is 19mm or maybe not depending on the manufacturer. My car is sold as having 250HP, not 186.425KW, even though it's made in Canada.

One thing that I've never been able to determine or understand about using metric is what unit to use. Why, for example, does one say that something measures 9835mm, instead of 983.5 cm or 9.84 m? Where does it stop using the smallest unit and move up to the next larger unit? I'm not being argumentative. I really don't know or understand. As an example, I am said to be 5'11" tall - not 71" tall. However, in metric, I am not said to be 1.8 metres tall. My doctor lists me as 180cm. Why am I not 1803mm? It would boost my ego being that tall. :)

[Ronald Blue]

One thing regardless of what you prefer is there are still many many pieces of equipment/machinery that are Imperial and that will be true for many more years to come. There are a lot of things made today that do use all metric fasteners such as engines. Then there are some that use a mixture on other parts. I'm okay with both but still do my measuring in Imperial and that likely won't change. I know the decimal equivalents for most fractions and convert back and forth as needed.

[Rod Sheridan]

Hi Grant, your doctor uses a form that requires centimetres, just like your license.

The only odd issue is that your weight is often stated in Kilograms, yet that’s not a unit of weight, it’s a unit of mass.

As for the choice of units, I base it upon the accuracy and scale requirements, millimetres are great for furniture, while metres are great for barns….Regards, Rod

[mike stenson]

Since we're constantly at 1g... It's fine for weight, on earth

Besides, we have enough of a problem with kilograms in the US.. I can't imagine having to explain newtons... So I'm good with accepting that 1kg is ~ 9.81 newtons.

[mark mcfarlane]

I started replacing tools and measuring devices when I retired 5 years ago. I decided to not go metric. I regret that decision. 5 years later I am slowly replacing measurement tools with metric versions.

For me, building in metric is simpler. I wish I had used that logic when I started buying measurement tools.

Pre-retirement I worked in oil exploration around the world and we mixed units on everything, e.g. it was not uncommon to see meters used for horizontal measurements and feet for depth. Velocities were always ft/sec but resistivity was ohm-meters, and on and on....

I also find Alexa very helpful in the shop for music and unit conversions.

[Gordon Stump]

I do both. Most woodwind instruments were made in Europe. So my woodwind pegs are turned in metric. Everything else is Imperial. Most of my digital devices can switch back and forth.

[Allan Dozier]

Someone mentioned temperature. While I agree that metric is probably the best for measurement of length, I think Fahrenheit is more useful than Celsius. First off it is significantly more accurate. Plus it covers the natural range of environmental temperature on a nice 100 point range. The degree that water boils is not all that significant when you consider all the other temperatures that we are interested in like cooking, metallurgy, etc.

[Jim Becker]

I started replacing tools and measuring devices when I retired 5 years ago. I decided to not go metric. I regret that decision. 5 years later I am slowly replacing measurement tools with metric versions.
Dual scale measuring tools have been really helpful in my journey. With my combo squares, however, I did have to acquire alternative scales due to their nature, but it takes about three seconds to swap should the need occur. All of the big machine tools were already dual scale with the exception of the drum sander and a DRO "fixed" that. I don't use Alexa for conversions because her main job in my shop is to stream WXPN.org, but since I have the computer for the CNC in the shop, if I need to do any conversions, I just use my browser.

[Rod Sheridan]

Someone mentioned temperature. While I agree that metric is probably the best for measurement of length, I think Fahrenheit is more useful than Celsius. First off it is significantly more accurate. Plus it covers the natural range of environmental temperature on a nice 100 point range. The degree that water boils is not all that significant when you consider all the other temperatures that we are interested in like cooking, metallurgy, etc.

Accuracy is determined by the measuring device, not the system.

Above and below freezing seem more intuitive to me than than having water freeze at 32 degrees, and I switched systems when Canada did in 1974……Regards, Rod.

[Rod Sheridan]

Since we're constantly at 1g... It's fine for weight, on earth

Besides, we have enough of a problem with kilograms in the US.. I can't imagine having to explain newtons... So I'm good with accepting that 1kg is ~ 9.81 newtons.

I’m not arguing, however having a bathroom scale in Newtons wouldn’t make any practical difference in my life, in fact as we get older we should prefer metric in Kg as the numbers are smaller…Rod

[Mike Kees]

I find that driving in the States takes so much longer to get anywhere, miles are so looong. Stupid but 600 kms whips by and 388 miles takes forever. Temperature completely screws me up, I find Farenheit completely illogical and the only thing I remember is -40C is the same as -40 F. Canada is supposed to be officially Metric but reality is we are stuck halfway between systems. I do not know anyone who will tell you their weight in KG's . At the same time gas is purchased in liters, this is so normal that only someone over 50 with a sharp mind could even tell you the conversion to a Canadian gallon. (4.54 L) Lumber and plywood will be imperial forever because the US is by far our largest trade partner and buy most of our lumber. In the shop I use both systems, Metric wins in thickness situations, my default is 20mm for solid stock. Imperial gets used because I am a Carpenter with 40 some years of experience measuring in this system. When I was apprenticing we worked on a large Church , on this job the plans were Metric. All the dimensions are in mm. Very interesting building in Metric with imperial plywood, basically measured plate lengths in Metric and layed out on 16'' centers after. Metric is so much easier to do all the math in your head.

[Allan Dozier]

"Accuracy is determined by the measuring device, not the system."


I see your point Rod and agree. A better term would have been sensitivity. I could have two tape measures with identical accuracy but if one only has marks at 1/4" and the other has marks at 1/16" I would find the latter to more useful. If the digital readout on my planer only showed 1/8" increments that would be unacceptable even if very accurate.

In another hobby of mine I find the metric system used much more in mechanical things like autos, trucks, tractors. I use my metric wrenches more frequently than SAE.

[Alan Lightstone]

Though having "normal" body temperature at 37 degrees Celsius is an odd number. And let's skip the discussion of "normal" body temperature. I could speak for hours about that. But we always measured patient's temperatures in Celsius also in the OR, yet on the hospital floors you would hear that a patient had a 102F fever. So, I guess, location matters. So odd...

I agree that water's freezing and boiling points at 0C and 100C makes lots of sense. 32F and 212F are just such strange numbers.

[Charles Coolidge]

I have no use for the metric system when measuring distances. Weights sure.

[Allan Dozier]

Yeah, 37, 32, and 212 are all odd numbers. So are flash points and melting points of different materials. My oddball thinking is that the boiling point of water is not important to most professions and when the average citizen brings up temperatures it doesn't involve boiling water. Heck, the boiling point of water is not even a constant, it varies significantly with the pressure. If I were king of a new country and had to come up with a temp measuring system I would say, Hmm what is the normal and natural temperature range of the environment and make that a 100 point scale. I know I am in the minority though.

[Brian Holcombe]

Kelvin makes sense, both Celsius and Fahrenheit use water as their standard. The metric system is great for the fact that the standards can be tested as opposed to needing to be stored somewhere. Beyond that I don’t see where it’s better than SAE. I find base 10 annoying for joinery work where I’m dividing into thirds and human proportion is helpful in planning things around human proportions.

[Mel Fulks]

The lines are too close , metric “yard -sticks” look like a kid painted over them. What good is a slightly longer yard-stick that requires
magnification ? Okay, if a sock gets kicked way under the bed you might have an easier time getting it out with metric .

[Rod Sheridan]

I have no use for the metric system when measuring distances. Weights sure.

Interesting Charles, why is that?

Regards, Rod

[Jay Rasmussen]

Some countries use Metric system others have put Men on the Moon – HA. Old toolmaker told me that years ago.

Metric is much easier than Imperial I think. Going back and forth takes a little time but not that difficult but I still think in inches.

As a side note, the Imperial system of measurement has been around a lot longer than the Society of Automotive Engineers (SAE)

[andrew whicker]

In engineering school, the professors would make us do imperial / English units from time to time.. collective groan from all the students.

lbm vs lbf? Btu, HP, etc. 12" = 1 ft? Water boils at 212 F, but 100 C? 4 Quarts in 1 Gal?

It feels like EVERY time the imperial / English people had a chance to simplify, they chose to complicate.


I do think, w/ time and use, that fractions get easy to use. And, of course, you have to memorize things like 7/8 = .875 or 3/16 = .1875 when you have to convert to decimal. The whole construction world is riddled with a few seconds or minutes lost with overworking our brains. I'm not sure what it's like in Metric countries, but 16" on center, 48" x 96" wide sheets, 8 ft (96") 2 x 4's, 18" drawer slides, etc. It works pretty well because we've fast tracked / processed the construction world so much, but when you DO have to calculate something...

How many times do you have stop and look at your ceiling while you think: "5 7/8 + 5/16".. it's easy, but you aren't always primed for it. Best to use story sticks, etc and just not calculate.


It has to be an absolutely HUGE number of collective extra time spent every day in the construction / building world of America due to the Imperial system.

[Rod Sheridan]

Some countries use Metric system others have put Men on the Moon – HA. Old toolmaker told me that years ago.

Metric is much easier than Imperial I think. Going back and forth takes a little time but not that difficult but I still think in inches.

As a side note, the Imperial system of measurement has been around a lot longer than the Society of Automotive Engineers (SAE)

True, however the US doesn’t really use the Imperial system, look at your gallon……Rod