Metric system

[32coupe]

We have been using metric for years

17mm is about 3/4 inch, at least a 3/4 inch wrench will work on a 17mm nut or bolt head.  

HHmm not quite, 19mm is closer to 3/4, 17mm is more like 11/16  

Easy really

[OldSub]

My uncle used to say after 3/4 inch it didn't matter any more...  Use what fits.

[Rrumbler]

HHmm not quite, 19mm is closer to 3/4, 17mm is more like 11/16 Very Happy Very Happy

Yeah, that's it, 19mm, or was it 18?  I dunno, it was something in that general neighborhood.  Besides, if one thing does not work, I'll try something else.     In truth, I do have a set of metric tools, and as time goes by, I am getting a bit better at sorting the things out in their own format; not much, but better.  

[Jbird]

I've been doing the "in head" conversions for so long it's just second nature. I can usually identify a threaded bolt, dia and pitch, inch/metric just by looking at it. The only problem I have is when I look at a 1/4-20 bolt and it has a 10mm hex head. I bought a bag of 1/4-20 oil pan bolts from ACE once, some had 10mm and some 7/16" hex heads. I think we should convert all of em over to clutch head screws.   Jbird

[enjenjo]

The only problem I have is when I look at a 1/4-20 bolt and it has a 10mm hex head.

Have you run into any of the studs on GM cars that are metric on one end, and fractional on the other?

[Jbird]

The only problem I have is when I look at a 1/4-20 bolt and it has a 10mm hex head.

Have you run into any of the studs on GM cars that are metric on one end, and fractional on the other?

Yup, the end that screws into the engine is merican and the end that the nut goes on is ferrin. Used to get out my fraction wrenches to work on an american car and my millimeter wrenches for them foreign cars. Now it seems like I have * near my whole tool box out to work on an american car.

[jaybee]

Yes, that bugs me more than anything.  Metric or SAE, either is fine with me.  Mixing both on the same job bugs me.

[Gilles]

I'm in the exact opposite situation as most of you! I use metric system every days for as long as I was able to turn a wrench!  There are these strange SAE bolts that we find in american cars  that are a problem!   Usually to find them I have to go to a tractor shop or industrial supplier, as some tractors and machine tools are american made. On my 32 roadster there are SAE on the 350 engine, the TH700 is metric  but bolted to the engine by non metrics! SAE on the front-end, but metrics on the rear due to the home-made four-bars. Metrics also on the body and everywhere it was possible. I couldn't find the long bolts for the starter. I had to make them, welding a too short SAE bolt to a 10 milimeter long bolt. Two years ago during a trip in USA I bought two "starter bolt kit" in a Autozone and a wallet of assortment bolts.

So the convertion to metric is not a problem as you.  

But I had to try another big conversion. First january 2002 we stop to use or 700 years old money, the franc, and started to pay with Euros. One Euro is 6.55957 franc! Do te maths!  Even 7 years later is not evident for some old persons to know how much they are paying. And even younger people have to convert to old francs when speaking about big sums, houses prices for exemple. I decided to think in Euros and to forget the francs. It works surprinsingly easily.  
I think the difficulty is to run in parallel two differents systems and try to convert every time. But after some time is automaticall thing. When I read on Street-rodder magazine "two inch top-chop" I think "5 cm top-chop"  55mph is 88 km/h.   70 mph is 112 km/h. And I don't have to calculate, It's in my brain. During a trip to the Engish street rod Nat's a friend said, reading the map "we can go there this night, it's only 100 km" I replied "No, it's 100 miles, 160 km!"

Gilles

[phat46]

Before i retired i worked for a Candian company in the U.S.  Most of the supplies we used were from Europe. We went back and forth pretty easliy, but most guys used the inch and foot measurements even when dealing with metric stuff. the steel rule we used was 50mm, but was always referred to as 2"  I did the Q.C. there for many years and dealt with the customers who came to inspect dies so I was able to "speak" metric with them fairly well, all tolerences were metric, so not only did I used metric measuring devices, I had to "calibrate" my eye to metric.
I just changed the front wheel bearing and hub on my '02 Dodge and it was a hodgepodge of American and metric, I just bring all the sockets and wrenches to the job anymore....

[enjenjo]

I just changed a idler pulley that was held on by 4 bolts, three metric, and one SAE

[GPster]

When I slid back the S10 motor in the chassis to be nearer the Jeepster's firewall I made plates of 1/2" steel that bolted to the holes in the crossmember. I drilled  the plates to to use Chevy V8 motor mounts upside down to fasten to the mount stands on the 2.5L four. The truck's crossmember had numerous extra holes in it for different engine configurations but I used them all so the plates would be mounted securly. Now the original mounts were bolted to the crossmember with bolts with shoulders on them. They were some metric size and somewhere in the de-construction of the S10 I had secured a collection of self-locking nuts with shoulders that were the same metric size. The metric nuts and bolts made a nice choice for use on the plate to crossmember mate and they were the same size as the factory holes but I didn't have enough to fill all the holes. So the 1/2" plate is bolted to the crossmember with metric and SEA nuts and bolts (and some of them are hidden and can only be accessed with a box end wrench that holds the shoulder of the nuts). The other end of the plates are drilled/tapped in SAE for bolts to hold the up-side down motor mounts (I didn't have the correct size metric tap and the bolts with shoulders wouldn't fit in the mounts). The bottom of the mounts point up and the long through bolt is SAE to go through the mount and through the metric hole in the bottom of the mount stands that is fastened with metric bolts to the side of the engine. This is the first time I have written all this down and I'll have to copy it and tape (Metric/SAE ?) it to the crossmember so I'll know what wrenches I'll need to take it apart. This is only half of it. Because the engine is further to the back the stock crossmember wouldn't work. I had to make a new crossmember so I made a "K" member (what language?). I used what I had available and could bend easily. I used 1" sch. 40 gas pipe. Try measuring it and finding 1" anywhere. The threads are supposed to be Int. but it's hard to find a nut to fit them and after three turns you think you cross-threaded it. My tool box still has open-end wrenches in it with file marks in them from when I had a BSA motorcycle. I have a 4", a 5" three 6" two 10". two 12" and one BIG crescant wrench. For the realy tough jobs I have abrasive discs for my 4 1/2" side grinder and a cutting torch. GPster

[Carnut]

I've always considered the size conversion to be similar to speaking a different language.

I've always envied anyone who is multilingual and can speak more than one language fluently.

I had two years of Spanish in high school and 2 years of German in college and can still only speak English. Flunked last semester of Spanish and barely made it thru German with the lowest grades of my college career.

Languages just ain't my bag.

I just can't speak metric.

What's really funny is that I am quite capable of 'speaking' various computer languages I've had to pickup in my activities. Heh, heh, right now I am quite fluent in HTML.

[Rrumbler]

I'm a lot like Phat46: before I moved from construction and maintenance back into operations, the company was sourcing more and more new equipment from Europe and Japan.  We were getting large high voltage power circuit breakers and transformers from both sides, and they were always a mish-mash of SAE/Metric.  In my tool box, I painted a red stripe on all of my metric tools, along with my own personal color.  I'm not quite as inept as I might let on; I did manage to muck through it all pretty well.  What struck me most was the engineering specs that some of the stuff had: SAE on the exterior fasteners and hardware, with the insides all remaining metric, as built in Sweden or wherever; why did they do that?   :?   I do think that it is a sort of "bilingual" thing, though; my grandkids speak both without any problem.