Metric nut sizes

[Jim.ME]

Do all 10 in. adjustable end wrenches open to the same amount?

No, there is no standard opening based on length.

 

[BarnyardEngineering]

19mm is so close to 3/4" they interchange.

LOTS of GM suspension and disc break fasteners ore 18mm.

...and of course, 18mm isn't always included in the set.

First time I went to do the brakes on my 2003 Chevy, none of my socket sets had 18mm. All I had was an 18mm 12-point combination wrench, which wasn't cutting it because the bolts were all Loctited. Of course I had the truck jacked up, the first tire removed, and the caliper off... AND it was my only means of transportation.

 

[bc]

Do all 10 in. adjustable end wrenches open to the same amount?

And do they all adjust? I have a few stuck ones and some with quirky acting gears that wd40 doesn't fix.

 

[Watthour]

They might have called it a spanner. About every country in the world that were settled or contacted by England early on were ruined by the King's English. Worked all over the Middle East. When I yelled for a wrench, they would bring me a spanner.

The Shibaura engine in my Ford tractor uses metric and also a British pipe thread for oil lines in the block.

Some of the gear reducers I use come from Italy. The oil ports in those are all BSPP. It's not quite as easy to find fittings in North America as one might think. I've even got a local shop to crank out special bronze/neodymium drain plugs for the application in two sizes, and they had a little difficulty in finding the 55° thread tools to machine them.

 

[bc]

Some of the gear reducers I use come from Italy. The oil ports in those are all BSPP. It's not quite as easy to find fittings in North America as one might think. I've even got a local shop to crank out special bronze/neodymium drain plugs for the application in two sizes, and they had a little difficulty in finding the 55° thread tools to machine them.

I've found the British adapters on Amazon. I've replaced some sae cross threaded fittings someone else put in that leaked. Then I finally just retapped the block for sae.

 

[will-max dairy]

I find myself needing more metric combination wrenches than I already have. I guess I'm looking for sizes that will not likely ever be used like the 25/32 socket in a set. I have a pretty complete set of metric combination wrenches from about 13MM to 20MM then the 24,30and32 MM want to fill in the gaps just not waste money on ones not used only once in a decade or less.

(Edit: for posterity's sake... the table below was created thinking about wrenches. It is next to impossible for the average human to smear a very large nut or bolt with a wrench that is 20mils oversize. If we were talking sockets, your 1 inch drive impact wrench will have no problem at all smearing a nut with that difference, if the nut is tight. As a matter of fact, on old, rusty bolts/nuts, if I'm using the impact to remove... I'll purposely try to pound the undersize on for a tighter than factory grip)

As you get into the bigger sizes, the difference between metric and english matters less and less.

If you already have every 1/16th covered above 3/4 inch to the maximum size that you need, then the utility of also having all of the metric wrenches of similar size is very little.

I had a moment of ADHD and wanted to fiddle... so... enjoy.

20mils was arbitrary... just over half a millimeter, which is ~39.4 mils

a "mil" is a thousandth of an inch...

And... in a pinch, you could always try the "SAE over," even for the yellow values; you'll always be less than a mm off. But... the risk of rounding grows with the mismatch...

 

[will-max dairy]

I'm gonna be in the minority here on this I think, but in my opinion adjustable wrenches are only useful when there is nothing else available or for bending/straightening stuff.

I can't recall the last time I used one for turning or holding a nut or bolt.

I have several collecting dust.

I have two big adjustable wrenches... I use them on plumbing fittings like unions and such.

I don't like to use them on any bolt or nut that I would regret smearing...

 

[bc]

I have two big adjustable wrenches... I use them on plumbing fittings like unions and such.

I don't like to use them on any bolt or nut that I would regret smearing...

And I have a couple of those large channel locks that come in handy for gripping big things.

 

[will-max dairy]

...and of course, 18mm isn't always included in the set.

First time I went to do the brakes on my 2003 Chevy, none of my socket sets had 18mm. All I had was an 18mm 12-point combination wrench, which wasn't cutting it because the bolts were all Loctited. Of course I had the truck jacked up, the first tire removed, and the caliper off... AND it was my only means of transportation.

Ahhhhhh GM...

Let me tell ya about the time I had my only car, a Pontiac 6000 all jacked up to work on the brakes... and the caliper bolts were Torx...

I borrow my brother's truck for an hour round trip to town and return with a set of torx sockets in hand... everything from, like T-10 to T-50 in increments of 5

I try the T-45... too small... I try the T-50... too big

I borrow his truck again... go to the Advance Auto... another one hour round trip; where I find that Pontiac used a T-47 that isn't in the set, but they were sold as individual sockets...

They just HAD to have that T-47... I'm sure that the exact torque calculation done by some engineer required it...

*sarcasm alert*

 

[bc]

Ahhhhhh GM...

Let me tell ya about the time I had my only car, a Pontiac 6000 all jacked up to work on the brakes... and the caliper bolts were Torx...

I borrow my brother's truck for an hour round trip to town and return with a set of torx sockets in hand... everything from, like T-10 to T-50 in increments of 5

I try the T-45... too small... I try the T-50... too big

I borrow his truck again... go to the Advance Auto... another one hour round trip; where I find that Pontiac used a T-47 that isn't in the set, but they were sold as individual sockets...

They just HAD to have that T-47... I'm sure that the exact torque calculation done by some engineer required it...

*sarcasm alert*

Everything is made requiring special tools that only the stealership service department knows about and has. Now you have to buy their scan software, Toyota comes to mind. Everything is snap together plastic parts and you have to know how that was done so you can take something apart without breaking it.

 

[farmersamm]

(Edit: for posterity's sake... the table below was created thinking about wrenches. It is next to impossible for the average human to smear a very large nut or bolt with a wrench that is 20mils oversize. If we were talking sockets, your 1 inch drive impact wrench will have no problem at all smearing a nut with that difference, if the nut is tight. As a matter of fact, on old, rusty bolts/nuts, if I'm using the impact to remove... I'll purposely try to pound the undersize on for a tighter than factory grip)

As you get into the bigger sizes, the difference between metric and english matters less and less.

If you already have every 1/16th covered above 3/4 inch to the maximum size that you need, then the utility of also having all of the metric wrenches of similar size is very little.

I had a moment of ADHD and wanted to fiddle... so... enjoy.

20mils was arbitrary... just over half a millimeter, which is ~39.4 mils

a "mil" is a thousandth of an inch...

And... in a pinch, you could always try the "SAE over," even for the yellow values; you'll always be less than a mm off. But... the risk of rounding grows with the mismatch...

Your chart, and I've seen others like it, is the reason that you receive, what you think, is an incomplete set of Metric wrenches when you buy one. The imported stuff omits sizes that roughly correspond to Imperial sizes.........assuming you already own a set of Imperial wrenches.

The Metric fans like to tell you how simple Metric is. No fractions. YOU EVER TRY TO FIND THE PROPER SIZE DRILL BIT FOR TAPPING A METRIC HOLE...................I had to special order a 10.2MM bit for some M12 holes. So, it ain't as simple as the idiots like to make out.

 

[BarnyardEngineering]

Your chart, and I've seen others like it, is the reason that you receive, what you think, is an incomplete set of Metric wrenches when you buy one. The imported stuff omits sizes that roughly correspond to Imperial sizes.........assuming you already own a set of Imperial wrenches.

The Metric fans like to tell you how simple Metric is. No fractions. YOU EVER TRY TO FIND THE PROPER SIZE DRILL BIT FOR TAPPING A METRIC HOLE...................I had to special order a 10.2MM bit for some M12 holes. So, it ain't as simple as the idiots like to make out.

Some guys... you suggest using a metric wrench on an SAE fastener or vice versa... "You can't use an inch wrench on a metric bolt!" No reason why, just, you can't. Show 'em the 3/4" / 19mm trick, and they'll accuse you of WITCHCRAFT!

Dealing with fractions exercises your mind. Makes you smarter. Being able to "conjugate" fractions in their most reduced forms (i.e. 3/32,1/8, 5/32, 3/16, 7/32, 1/4) is a skill that your mind will subconsciously use in countless applications. Pretty sure it's the same part of the brain that you use to say the alphabet backwards, so you won't fail that sobriety test even though you haven't had anything to drink!

Oh, and the world uses BOTH to varying degrees everywhere, and it's not just because of "lazy Americans." There is just so much old stuff out there that was built using feet and inches, that it will never go away no matter how much poo people fling at each other.

 

[GChief]

lazy Americans."

I work all over the world...QFT

 

[will-max dairy]

Your chart, and I've seen others like it, is the reason that you receive, what you think, is an incomplete set of Metric wrenches when you buy one. The imported stuff omits sizes that roughly correspond to Imperial sizes.........assuming you already own a set of Imperial wrenches.

The Metric fans like to tell you how simple Metric is. No fractions. YOU EVER TRY TO FIND THE PROPER SIZE DRILL BIT FOR TAPPING A METRIC HOLE...................I had to special order a 10.2MM bit for some M12 holes. So, it ain't as simple as the idiots like to make out.

English drills and taps are just as complex. Generally, it's a matter of... how deep is the thread? And ...how hard is the material...

Once I see that an M12 thread of a certain type needs a 10.2mm, I would tend to remember the 1.8mm difference and they apply it to fasteners close to that size...

Your chart, and I've seen others like it, is the reason that you receive, what you think, is an incomplete set of Metric wrenches when you buy one. The imported stuff omits sizes that roughly correspond to Imperial sizes.........assuming you already own a set of Imperial wrenches.

The Metric fans like to tell you how simple Metric is. No fractions. YOU EVER TRY TO FIND THE PROPER SIZE DRILL BIT FOR TAPPING A METRIC HOLE...................I had to special order a 10.2MM bit for some M12 holes. So, it ain't as simple as the idiots like to make out.

13/32 would only be about 5mils too big to drill for that tap...

I mean... is a 10.2mm drill harder to find than a 27/64 to drill for a 1/2-20UNF?

drill sizes for taps are funny... either metric or imperial...

 

[will-max dairy]

If it grabs the bolt and turns it without slipping... or drills the hole for the tap... I couldn't care less if the units are imperial, metric, Klingon... whatever... I know my conversion factors; and I'm not afraid to use them, lol. Before I order anything special of either type... I'll punch a few numbers on my calculator and look at what I have around that might do the trick.

 

[stdsch40]

English drills and taps are just as complex. Generally, it's a matter of... how deep is the thread? And ...how hard is the material...

Once I see that an M12 thread of a certain type needs a 10.2mm, I would tend to remember the 1.8mm difference and they apply it to fasteners close to that size...

13/32 would only be about 5mils too big to drill for that tap...

I mean... is a 10.2mm drill harder to find than a 27/64 to drill for a 1/2-20UNF?

drill sizes for taps are funny... either metric or imperial...

That is why there are several sets of twist drill sizes, letter series, number series, and fractional series. Earlier I mentioned it would be nice to have a full metric series too, I just don't have the money for them now.

 

[tom upton]

Just a bit of trivia from an old retired Millwright who still likes rules of thumb. I think I have mentioned on here before that a good way to determine tap drill size when you are no were near a tap drill chart and your memory has you wondering if you have the onset of dementia is the following which applys to imperial and metric. Actually a little easier in metric than imperial as the tap you are about to use will have the pitch allready figured out for you whereas in imperial you have to do a little math to figure it out.
It is simply size of thread minus one pitch.
for example 3/8-16. First divide 1 by 16 to give you the pitch of 1/16 ( .062) Then 3/8 minus 1/16 is 5/16
Like said metric almost has it figured out for you. example: 10mm minus the pitch of 1.5 is 8.5
Some diehard perfectionist machinist will say thats not exact but like they say in horseshoes and hand grenades its close enough.

 

[BarnyardEngineering]

If it grabs the bolt and turns it without slipping... or drills the hole for the tap... I couldn't care less if the units are imperial, metric, Klingon... whatever... I know my conversion factors; and I'm not afraid to use them, lol. Before I order anything special of either type... I'll punch a few numbers on my calculator and look at what I have around that might do the trick.

https://ukonic.com/products/star-trek-klingon-batleth-6-in-1-multitool-kit

 

[will-max dairy]

https://ukonic.com/products/star-trek-klingon-batleth-6-in-1-multitool-kit

I would buy one for myself... except I would keep it in my pocket and then get it confiscated and lose it going through security at a hockey game, or whatever...