Metric, SAE or Both?

[ed_v]

Like others said, it depends on what you're working on. I have both SAE and metric. I did not buy all my tools at once. They were purchased as needed.

It's not really a big deal. Go buy yourself a good 1/4", 3/8", and 1/2" ratchet to start. Then order a craftsman 176 piece socket set (under $200) and a small SAE and metric wrench set. Perhaps get yourself a torx bit and hex key set and you have the basics to get started.

Ed

 

[0.511MeV]

I buy metric, as all my vehicles use that.

Barely anything is SAE that I own or use, and if it is, I have a Craftsman Dogbone wrench to handle it.

 

[royce71]

I buy both, but the metrics are well used and the SAE look brand new.

 

[Swan]

Both, and British Standard Whitworth (the first thread standard). Metric for modern cars and Japanese bikes, SAE for my later British motorcycles and old Schwinns and Whitworth for my pre-1968 British motorcycles.

 

[bwringer]

Metric. I won't buy a set of anything if it's fluffed up with SAE stuff that's useless to me. I have a junk drawer that I toss the SAE stuff into that only gets opened when I have to work on a lawn mower.

American cars have been metric for 30+ years, but they still use all sorts of oddball sizes. For example, 13, 15, 16, 18, 21, 22, and 23mm were all found on the last Ford I had the displeasure of working on, with a random assortment of Torx fasteners precisely where it's the least convenient... aargh.

99% of the the stuff I work on is Japanese (mostly Suzuki and Kawasaki motorcycles and Toyota cars), so the JIS sizes needed are pretty predictable.

 

[Arne73]

I have both fractional and SAE at work. Most of our machines are european but there's a lot of fractional equipment around too. Some operators bring in their own tools and make minor adjustments. Most don't know or can't tell the difference between metric and fractional. Rounded off fasteners make me crazy.

 

[ihateminimumwage]

I'm buying both, since I barely have (or use) any Metric. I've mostly only had SAE in all sizes since I first turned a wrench (I think I had a 10mm mixed in there too), didn't even buy a real set of metric sockets & wrenches until after I bought an 80 Toyota 4x4 (and that was maybe 5 years ago ).

Now I'm going to school for Diesel Tech, so I started buying up some Metric stuff, but it is barely used. Most of the equipment we're being taught on is older and American, and everything so far brought in by customers is SAE as well (CAT, Deere, Case, etc). Besides working on an old Deutz engine and rebuilding some hydraulic pumps, I haven't touched my metric tools in the shop.

 

[#1SomeGuy]

I guess I should mention that I have up until this point bought both so I have a fairly decent collection of sockets from both in 1/4, 3/8, and 1/2 drive and have wrenches from little up to the inch or so size. It's the 3/4 drive I'm debating at the moment

It's also interesting that I almost always find myself reaching for metric these days, my SAE stuff hardly gets used and yet I have a drawer full of the wrenches.

Good replies here though.

 

[wornoutoldman]

SAE will be less expensive initially and in those sizes of fasteners they will be close enough for government work. But get both if money is not a concern.

 

[purpurite]

Metric is 99% of what I use on all of my cars or anything else. But you can't have a toolbox without at least basic SAE sockets.

The poll responses that confuse me are the only SAE answers. What the heck are those guys working on where they never see any metric tools?

 

[AZ_Catskinner]

In ¾" drive, I've always found more call for SAE than metric. That said, I only own two metric ¾" drive sockets, and have only used one (36mm) with any regularity.

It really depends on what you are doing with it. In most cases, I'd recommend spending the money on an SLX80A (25" long ½" drive ratchet) and the smattering of larger sized sockets you may need than a ¾" drive set that mainly serves to gather dust.

 

[AZ_Catskinner]

Metric is 99% of what I use on all of my cars or anything else. But you can't have a toolbox without at least basic SAE sockets.

The poll responses that confuse me are the only SAE answers. What the heck are those guys working on where they never see any metric tools?

Old cars, construction, BIG industrial equipment. If it weren't for my OCD, I could throw away my 36mm and just use an 1-7/16" at work, eliminating any need for metric tools at all.

Out of my (thankfully downsized) fleet, only the XJ and the Dodge have succumbed to the metric system, while the "real Jeeps" (1944 MB and 1980 CJ7) make snide comments toward them. The CJ7 had better watch it's attitude though, as it is currently loaded with metric fasteners, in the form of the Ikea Raskog sitting on the tailgate awaiting me to drag myself out into the garage and put it together.

 

[purpurite]

Old cars, construction, BIG industrial equipment.

Interesting. Dinosaurs, essentially. Makes sense, though.



Here's a piece of trivia for you guys... what do these three countries have in common—Liberia, Myanmar and the United States?






















A: They are the ONLY three countries in the world that have failed to adapt to the Metric system.

Go figure. Us Yanks have issues with change and apparently, common sense.

 

[mailpup]

To some of us, having SAE and metric system fasteners is not necessarily a negative thing. We can look upon it as an opportunity to buy more tools.

 

[AZ_Catskinner]

Interesting. Dinosaurs, essentially. Makes sense, though.

Even European sourced equipment will have SAE fasteners or a mix of both (the mix is especially prevalent in smaller stuff). Sometimes the European manufacturers bought the patents and rights to machinery that originated in the US, or they will follow US standards to design replacement equipment to drop into facilities that were originally built with US sourced equipment.

Rarely will you see a metric bolt over 24mm. At that point in size, SAE usually takes over. IIRC DIN grading ends at 36mm.

 

[NHBandit]

NHBANDIT! the flexible tool i had one once! never knew what it was for so i gave it to a friend. wish i knew that before i gave it away, i could use from time to time.

now i know! haha great.

Yep and the well prepared mechanic should have an old section of heater hose slid over the handle as an insulator to prevent getting "bit" when adjusting the points on a running engine. Now I have every tech on here under the age of 40 scratching their heads and thinking WTF is this guy talking about....

 

[Outline]

I hate it when you find a nicely priced set and they have those stupid sizes in there. Who the hell uses a 23 and 25mm? 7-19, 21, 22, 24, 30, and 32mm has been all I've ever needed personally. I also have never NEEDED a swivel socket or crows foot.

You forgot the 27mm...

Usually those strange sizes are used to get a higher number of tools into a set. Most Dutch companies & consumers that buy tools look at the price vs. the number of tools they get first. If that ratio is good, a lot of consumers won't look further at quality and so on.

An example of a toolbrand which is good in getting their tool count numbers up: http://www.sonic-equipment.com/ Look at their online catalogue: http://www.sonic-equipment.com/en/content/10/Catalogue.html and my comment in the 'Tools from the old World'-topic.

I've used a 25 for something. I can't remember what though. It was either a BMW or Mercedes. A really useless size is a 20mm...and yet I bought one to complete a set that didn't come with one just in case.

20mm is really useless but it's the only one I'll except if there's a 19mm and 21mm in the set. The other 'strangers' are a real no-go for me!

American cars have been metric for 30+ years, but they still use all sorts of oddball sizes. For example, 13, 15, 16, 18, 21, 22, and 23mm were all found on the last Ford I had the displeasure of working on

It's news to me that US cars have been Metric for 30 years! I never worked on them and they are quite scares here so I never had the chance to find that out for myself.

For those sizes: http://www.gedore.nl/Prijsbestand/gpk_2012_NL/pdf/2688808_Kat_GPK_12_TEC_NL.pdf on page 654. It's Dutch and the PDF is 90MB big but the fastest I could find! Let me know if you need help with the diagram!

Also good to know: 17mm (M10) and 19mm (M12) are the old sizes (officially up to 1985). Example: Westfalia Automotive (my preferred towbar supplier) uses the 'new' sizes 16mm & 18mm. A lot people do not know that and wreck their bolts using 17mm & 19mm....

Rarely will you see a metric bolt over 24mm. At that point in size, SAE usually takes over. IIRC DIN grading ends at 36mm.

Not true: When I was working for King Tony I regulary sold bigger sizes, up to socket 150mm. Not much and sure specialty but nonetheless sold them. Used with 1-1/2" impact driver.

 

[pipsters]

Pretty much any work done around the house will use SAE stuff. Great example is lag bolts.

 

[marlinspike]

You forgot the 27mm...

27mm is common on Mercedes.

 

[kc-steve]

Even European sourced equipment will have SAE fasteners or a mix of both (the mix is especially prevalent in smaller stuff). Sometimes the European manufacturers bought the patents and rights to machinery that originated in the US, or they will follow US standards to design replacement equipment to drop into facilities that were originally built with US sourced equipment.

Rarely will you see a metric bolt over 24mm. At that point in size, SAE usually takes over. IIRC DIN grading ends at 36mm.

So true about SAE mixed with metric.

Steve

 

[kc-steve]

Interesting. Dinosaurs, essentially. Makes sense, though.

Even European sourced equipment will have SAE fasteners or a mix of both (the mix is especially prevalent in smaller stuff). Sometimes the European manufacturers bought the patents and rights to machinery that originated in the US, or they will follow US standards to design replacement equipment to drop into facilities that were originally built with US sourced equipment.

Rarely will you see a metric bolt over 24mm. At that point in size, SAE usually takes over. IIRC DIN grading ends at 36mm.

So true about SAE mixed with metric. When I check prices for bolts and nuts at the hardware store, I've found metric to be costlier. So any manufacturer will likely be considering those costs as well when they produce something.

Like I said earlier as a seller, I sell more SAE tools than metric but not by much.

Steve

 

[AZ_Catskinner]

So true about SAE mixed with metric.

Steve

We got a pump a while back that had a "normal" NEMA face for mounting the motor, with SAE (5/8-11) tapped holes for mounting, and @&*#ing metric holes (M20) tapped for the lifting eyes. There never seems to be any rhyme or reason behind the mixture - just totally random.

 

[Rickster]

I voted both but I'm not a tech, just work in the garage on my old Mustang and family vehicles. I can tell you that when selling the metric move faster and for more money than the SAE.

I've been trying to beef up the metric sockets in the toolbox, what sizes do you find are the most used in metric??

 

[byoungblood]

I said metric because that's really the only thing I buy new any longer.

My SAE sockets, for example, have become a bit of a hodgepodge because I've just bought whatever I've run across that was in good condition at yard sales, pawn shops, classifieds here, etc., to fill in the gaps and replace missing sockets from the Craftsman set I got 19-20 years ago.

But I use both fairly regularly. Usually the SAE on household stuff, metric on the cars, and increasingly more often on power yard equipment too. I suspect we'll probably never get away from SAE entirely, at least not in my lifetime. Threaded fittings of all types will probably be the last SAE holdouts simply because unlike a car, structures tend to hang around for quite a while longer, and the cost of retrofitting would just boggle the mind.

 

[Hotz]

24 mm is standard for oil pressure sensor for most engines of European origin, here in Brazil GM, Ford, Fiat, VW .. All use ..
The Japanese now use measures 7/9/11 mm, for threads or keys (Question of space for tools).

 

[rocco]

everything i work on around the house is SAE, the Camaro and Plymouth coupe are SAE, the rest though like the new cars, the RV and Scirocco and tractor are all Metric, so it's really a mix. I buy everything in both when i get something new.

 

[AZ_Catskinner]

Structures tend to hang around for quite a while longer, and the cost of retrofitting would just boggle the mind.

Bingo! Sometimes you've just got to stick with what was originally there.

 

[topdog849]

so I'm a new tech fresh out of school. I have both in sockets and wrenches but I have yet to touch the sae so far. I'm still unsure when to expect them. as far as I know from what I have gathered here only domestic cars lug nuts, old carbureted domestics, USA built machinery, and engines on domestics yet everything else on the chassis metric. what am I missing?

 

[celticbhoy]

I just buy metric. Working on the vehicles that I do, all I need is Metric.

 

[chevy302dz]

Actually SAE fastners still make it onto many newer cars even forigen models. They just don't come on from the factory nearly as often as they did even a few years ago. The aftermarket still makes many of their products in SAE and will continue to do so for many years to come.

 

[Rico.]

It's the 3/4 drive I'm debating at the moment

I think once we get into the 3/4" drive sizes.... over 32mm or 1-1/4"
as long as the fasteners are in ok condition you can get away with just having
a full set of metric sockets, especially if you use only 6 point sockets, and you
can use them quite happily on metric or SAE nuts and bolts.

One caviat.... If the fastener you are accessing is very mission critical, then I would
always advise using the correct tool no matter how big the fastener is, just to make
sure. But for household or DIY automotive use, you can happily use metric sockets
on SAE fasteners over 1-1/4", like I said, as long the fasteners are in good condition.

Anything below that size is a judgment call based on condition of fastener and torque
involved, but in those cases I would advise using the correct SAE socket or spanner.

 

[Dave455]

Well, only you really know what you work on, and what you need, but unless you work for a franchised dealer, work on exclusively BMW's or somesuch, and never touch anything away from work, you need both!

If you are looking to reduce costs, just buy the common sizes!

Here in the U.K. I find myself needing Metric (of 3 different standards, ISO, SI and JIS, all of which use a different range of nut sizes) SAE (we call them A/F) Whitworth/BS and BA! Then you've got hex bits, torx bits and so on, and just when you reckon you are sorted you find a Ribe screw or a Torx plus!

Ain't standardisation great!!

 

[Toolman12]

What i do for a living requires both sets the vehicles are metric but the hardware that comes with the equipment i install is SAE so i am stuck between a rock and a hard place.

 

[BK13]

I always wonder why people ask what they should get... How are we supposed to know what you work on?

 

[Outlawmws]

Resurrecting an 18 MO thread?

 

[neuralsnafu]

****, i just voted on an 18 month old post...

 

[M6erfan]

I HAVE both but generally only USE metric. I take care of a fleet of my families' cars/trucks: BMW, Toyota, Nissan, Jeep (new), and a 40 year old Yamaha 2 stroke bike. I haven't used my SAE sets in quite a while so when I BUY, its metric all the way.

SAE does come in handy for household chores though...

 

[neuralsnafu]

SAE does come in handy for household chores though...

My friend just bought a house, so I know this all too well... had to go through and dig up all my SAE to fix stuff...

 

[Drake9]

I use SAE the most but have both. In the process of upgrading my tools to nice USA made stuff and going with both

 

[wild cowboy]

20mm is really useless but it's the only one I'll except if there's a 19mm and 21mm in the set.

20mm is required for many GM air conditioning nuts - such as C/K/Silverado truck