Why are we still not using the metric system in the USA?

We did convert to metric. ALMOST. Now we get to deal with metric and Imperial measurments. Then when I drive acrooss the St. Claire river I can buy fuel in US gallons.
Use a tape measure with USA markings.Biggest mistakes are conversions.
I once watched an old carpenter measure a wall, walk to the lumber he needed to cut, he never rolled up his tape measure, he marked the piece he needed and started cutting. When I walked over to watch him cut, I noticed his tape measure was so worn out it had no numbers anymore,, all he did was transfer the distance he needed. He could have used a string and it would have given him the size he needed.

-- "My mission in life - make everyone smile !"

I use Fastcap tape measures that have both scales on it.

-- I don't make mistakes, only design changes....www.dgmwoodworks.com

I wonder if anyone makes a decimal imperial ruler or measuring tape? It seems this would address your not wanting to work in both SI and imperial and resolve the fractions issue…I know you can get decimal inch digital calipers.

-- "Checking for square? what madness is this! The cabinet is square because I will it to be so!" Jeremy Greiner LJ Topic#20953 2011 Feb 2

The Starrett Digitape converts imperial to metric and vise versa. It also
does inches in 100s, which goes well with dial caliper measurements.

In guitar making I’ve learned to think in metric in small increments and
10ths of an inch.

It may seem ridiculous, but I basically think in three systems when I do
woodworking, but I work to “relative accuracy” which mean when you
make a mortise you measure it with a caliper or whatever, but you
ignore the measurement and use the measuring tool to make the tenon
to fit. This is the way they did it in biblical times too, with story sticks
and “thumb widths” (which I use too, in rougher work). When you
work to relative accuracy more you learn to make parts to fit together
regardless of the math – it’s about relationships and proportions and what
looks good to your design sensibilities.

Problem is that have have talked to other woodworkers from other countries who ask the exact question as use, only in reverse. I don’t think it is an issue of which system is used. I think it boils down to an issue of not having a universal system worldwide when some of us get plans from sources all over the world. I just had a bear of a time with measurement conversion on the flip flop of what you have had problems with. I had plans with metric measurement, all the way down to the 2mm and 4mm slots in parts that had to go inside of each other. Well, it throws you a curve ball when you cut those patterns with 4mm slots and 1/4” plywood (or 1/8” if I’d been able to even get that) has to go into that slot.
I have no preference one way or the other. I can use both. I just wish that the world would get on the same page and use one or the other.
Dangit!
I just remembered. If they choose the American system, the project I just finished would have still given me problems. It was drawn from a seventeenth century plan that used metric. If they’d choose metric, I have plans that were drawn in the nineteenth century using inches.
Looks like the great measurement compromise still wouldn’t solve all my problems. So I guess I’ll stay out of this discussion like I usually do every time it pops up (and it does from time to time).

-- http://wddsrfinewoodworks.blogspot.com/

I’m a Canadian, and was born late enough last century to have grown up using the metric system. However, I use the Imperial system for all my woodworking. For rough measurements, I find the imperial system a lot easier. It is simpler to look at a tape measure and see the fractions, rather than to have to count out the millimeters. I can see 7/8” a lot quicker than squinting to see if something is 7mm or 8mm. I agree though, for accuracy, the metric system is superior, really, anything less than 1/8” I start having to scratch my head. When I measure stuff with my digital caliper, I often get strange fractions eg. 17/64 which is really frustrating because I can’t quickly “see” the measurement in my head.

-- Rob, Sault Ste. Marie, Ontario

The other thing I want to add is a big “amen” after reading William’s post. Well put. Sure gets tiring having to have 2 sets of wrenches, allen keys, sockets etc.

-- Rob, Sault Ste. Marie, Ontario

I have been around scientific types all my life, so both systems of measurement are pretty natural to me. I tend to convert fractional sizes to decimal in my head, now converting those SAE decimals to metric is a bit more calculation intensive, but not a big deal…

I know that most manufacturing industries that are still in the U.S. have for the most part converted. Now I have had to deal with both U.S. manufactured machines, as well as foreign manufactured machines that have had fasteners and threads in both systems of measurement…

I think due to the history, and the LARGE amounts of existing structures and systems, things like dimensional lumber, and plumbing fittings are going to be the inch system for years to come…

-- Manufacturer of fine quality sawdust since 1984. Comments and advice on my shop welcome. Check it out at http://lumberjocks.com/dbhost/workshop. Gladly accepting shop build donations!

Wow, don’t get me started. lol
Of course the Metric System is a far more superior measurement system. It’s linear and other measurements can be used in the appropriate large units, small units and micro units – all of which are translatable up and down.
Working in 2 systems is not the way to go, “there can be only one”. The US and Liberia are committed to be the last hold outs using a very antiquated system whose measurement origins are from noses, fingers, feet – all without any relationship to each other. When Liberia goes modern, the US will become a large island using a non world standard measuring system.
But it is strange that even though the US public decries being asked to use the metric system, they allow for it to be used in Airplane and Space engineering, medicine, electronics, new autos etc. —the list goes on. Do you know of anyone who over the past 4 decades that has ever purchased an 1-3/8 (1.779”) roll of camera film? – me neither, it’s 35mm.

-- Roger-R, Republic of Texas. "Always look on the Bright Side of Life" - An eyeball to eyeball confrontation with a blind person is as complete waste of Time.

Well said Rob, those are exactly my headaches. I know how big 7/8 or 1/4 is but I need a calulator to figure out that 17/64 is just a hair over 1/4. But a number like 0.26 is really easy to tell that it’s a hair over .25. And having to own 2 sets of tools and then trying to figure out which set I need depending on which machine I’m trying to work on drives me up a fricken wall…

-- Don - I wood work if I could. Redmond WA.

As for the “two sets of tools” problem, you are a lucky dog if all you have to do is figure out which set to use on which machine. I done mechanic work for thirteen years. On cars and truck from american companies made after about the mid-eighties, it was easy to tell which set your needed to work on them, BOTH!
Seriously, it was always a major frustration. It even got to the ridiculous point that us mechanics just had to learn which metric sizes were close to the SAE measurements and hope the bolt wasn’t so tight that you stripped it out by using the wrong tool. For example, 1/2” and 13mm bolts can usually be take out with either size tool. I’ve replaced alternators for example. The long pivot bolt through the top of the part was a 1/2” bolt with a 13mm nut on the backside. Who would even make a 13mm nut to fit a 1/2” bolt? WHY?! The bolt on the bottom that held the tension would be a 15mm. There were four wires held on the back by smaller nuts, 5/16”, 8mm, and two 10mms. Can you say ridiculous?
By the way, my example isn’t a joke. That is a perfect, real world example of an alternator on a vehicle. It drives mechanics crazy.
On another note you may find interesting though about tools, guys, the tools confusion technique of automakers went way beyond SAE vs. metric. In the nineties they really started using torx fasteners in odd places, and in very odd sizes. Then on top of that they added some with the “safety” feature of the little round tip in the middle that made mechanics have to rush out and buy a whole new set of tools for. Then (Ford especially) got bad about using what I call reverse torx. This was nuts and bolt heads that had twelve point sides instead of the typical six. This required you to use twelve point sockets or twelve point box end wrenches. To make it more difficult, they installed some of those (somehow) in places that you couldn’t fit a typical box end wrench withougt first grinding some “meat” off of them to fit between the top of the fastener and whatevever else was in the way. Of course, every time they done this, FoMoCo sold their “special tool” for getting to that exact accessory. The special tool cost so much though that you came out cheaper buying several extra sets of tools just so that you could modifiy them for specific tasks. I still have tools that have been grinded on, heated and bent to funny shapes, hacked off real short, and extended by welding pipe in between two cut end of the same wrench, all for special purpose wrenches that usually served the purpose of doing one single job on one single make and model of vehicle.
Don, you brought it up, the two sets of tools thing, but before I climb down off my soapbox, I’ll throw in one more for you just for fun.
In 1962, International made a 152 slant four engine for their scout trucks. Every bolt on it was allen head.

-- http://wddsrfinewoodworks.blogspot.com/

William; I’ve done a lot of work on cars as well, and the lack of standardization in the auto industry, or as you put it even in one car is frustrating. I’ve rounded my share of bolt heads using metric because the other bolts were metric, except in one… Torx…another excuse to have to buy another set of sockets, and screwdrivers.

-- Rob, Sault Ste. Marie, Ontario

Listening to all those mechanical stories ! Now I understand why the mechanics used to scream when I drove my VW beetle into the shop back in the 70’s. He sold me the used car, threw in a set of open end Metric wrenches and metric sockets.
TODAY I joke about my “Cresent wrench” being Metric, or the “pipe wrench” being left handed . No joking about the “Vise Grips” ! lol
Luckily our 4×8 sheets of plywood are still around. Metric thickness tough, messes up the dado set.

-- "My mission in life - make everyone smile !"

ahh conservative americans, don’t like change hehe.
change is never easy, but sometimes you better just bite the nail.
lucky for me we switched to metric in europe 200 years ago, at least the whole usa has the same outdated system. before metric every country or even city had it’s own silly system.

guess you could compare it to when we switched to the euro 9 years ago, givng up your own currency and it’s history is not easy. you need to learn the value of money again, but now that we adapted life is so much more easy. especially for me because half my customers are dutch.
can you imagine 15 countries getting together and agreeing to change their monetary system, while 1 country has been trying to change it’s measuring system since the 19th century!

I don’t care if it’s metric or imperial, I just wish we were working with one system worldwide. Since the metric system appears to be the future for the US and it is well established in the rest of the world – let’s get there faster.

I have 2 complete sets of wrenches and 2 sets of drill bits. I recently had to get an adaptor to handle router bits with an 8 mm shaft. I thought the post supporting the tool rest on my lathe was 1” in diameter and I ordered a new one. Only after I got it did I realize that the post is 25 mm. You cannot put a 1” post in a 25 mm hole.

Compared to most other industries, I think carpentry and woodworking are two of the slowest to make the transition.

-- Rich, Cedar Rapids, IA - I'm a woodworker. I don't create beauty, I reveal it.