Have you EVER needed a 16 or 18mm wrench? (Do these hex sizes really exist?)

[myway]

Yes on both sizes can't remember where I needed them now but I have both now. what about 9mm an 11mm another size I have used maybe once. Dan

[Aaron D.]

9 and 11 are VERY common. Not like 13 or 10 though.

[JoeW]

In my early days as an import car mechanic, 9, 16 and 18 mm wrenches were not included in Snap-On sets. In the 80s when the American car companies switched from inches to metric, 16, 18 and 20 mm became more common. It's funny how, depending on country of origin, hex sizes differ on the same size bolts. For example, an 8 mm bolt on a European vehicle has a 13 mm head, while the Japanese use a 12 mm. On a 10 mm bolt, most Europeans have a 17 mm head while the Japs use a 14 but, and the Americans use a 16mm. I've found a lot of use for an 11 mm on Swedish cars but, they use 7 mm bolts instead of 6 mm. 
My question was, when I bought my first Craftsman tool kit upon entering trade school, why was there a 25/64" open end wrench included? Probably so 20 years later I could cut it up, weld a 1 1/16" socket to it and make a Guzzi 5 speed special tool. I'm sure that's what Sears had in mind.

[RANDM]

Yes, Peugeot uses odd sizes.  I guess it's a French thing.  I worked on my dad's growing up.  Frustrating.

Yep - 9's & 11's too. Still - you didn't have to do that much
that often, the 504/5's were tough buggers.

Maurie.

[Kentktk]

Just used 18mm on a 2000 Volvo suspension last week

[Bob Wegman]

VW uses a lot of 16 and 18mm sizes.

[redrider90]

I use my 16 mm when I cannot find my 5/8" socket and use my 18mm when I cannot find my 11/16" socket although 18 to 11/16 is just a little loose.
Same for 13 mm to 1/2" and 10mm to 3/8".  My tool box is hit or miss when looking for something.

[Sasquatch Jim]

  Years ago I bought a set of wrenches that had a 6 point socket on one end while the other was an open end wrench.  They were beautiful and strong and very handy.  However, even though the had both 16mm and 18mm sizes, there was no 14mm wrench in the set.  Thinking this was an omission, I went to the store and looked at those wrenches again.  None of them had a 14mm wrench in them.  I think the people who made them hated Japanese machinery as 14m is extermely common on Japanese stuff, whereas many European machines go from 13 to 15 with no use of 14mm fasteners.  I found it impossible to obtain a 14mm wrench with the socket open end style.

[Moto]

Well, live and learn. I'll look at my 16 and 18mm's with new respect from now on. Sears too.

Thanks for the replies.

Moto

[rodekyll]

Germany, heavily endowed with mineral resources, used 10, 13, 15, and 17mm bolt heads because iron ore and smelting was cheap.

Japan does not have their own mineral resources.  They have to import.  They save millions of pounds of iron and significant weight per vechicle by reducing the head sizes from 13-> 12, 15->14, etc. 

11mm is hugely common on small hydraulics like brakes and fuel.  It's also a very direct fit to 7/16.  So it's one place you can carry a single wrench for two fits.

[pikipiki]

Yes on both sizes can't remember where I needed them now but I have both now. what about 9mm an 11mm another size I have used maybe once. Dan

Ever adjusted your Guzzi foot brake for height? From memory, V7 foot brake is a 9mm.

[Scott DeRoss]

I remember 11 mm and 16 mm not being in the set and not that common. I believe 11 mm was equal to 7/16" and 16 mm was equal to 5/8" so years I never had them in my set. But I do now!

[Sheepdog]

If I'm not mistaken, my '87 XL600 required a deep 18mm socket for the spark plug...

[leroysch]

Used 2 18mm sockets on the nuts used by the OEM centerstand to get the rear end of my V11 up.

Was a lot easier to get them captured.

[Lesman]

Spark plugs in the "C" range are 16mm or 5/8

[jazzamoto]

Used 2 18mm sockets on the nuts used by the OEM centerstand to get the rear end of my V11 up.

Was a lot easier to get them captured.

I do exactly the same on my V11 Cafe Sport. Even built a little fixture on my stand to hold the sockets on place.