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Skipping sizes in Metric Sets?

GSMotorrad

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Mar 8, 2012
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I'm trying to figure out if I should get all congruent numbers, or opt for these sets that skip "useless" sizes.

Some wrench sets skip 20mm. Has anyone ever needed a 20mm? I can't say that I ever have. What about 23mm? I usually go from 32mm all the way to 36mm, so are all those sizes in between going to be a waste of money?

Do we get these "in-between" sizes, only to make our sets aesthetically pleasing - because that IS important, somewhat.

I'm looking at Hex Socket kits and trying to decide if I need the 7mm Hex, or the 9mm Hex. I've never needed those sizes, but if I ever do... :confused:

I don't think I've ever needed a 16mm or an 11mm either, none that I can recall.

I'm so confused trying to buy these sets; do I get larger sizes and skip the "never used" sizes, or do I get every single number in order?

I don't want to be "missing" any sizes, but I also don't want to get tools I'll never use in my entire life. What's the general consensus here?
 
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98TJ

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7mm hex is popular when working on interiors of vehicles. Ford specifically.

It bugs me to not have a size. I have 10-25mm in 1/2" drive but don't have a 26mm. Oddly enough, my Hansen socket tray doesn't have a 26mm slot.

I also don't buy sockets just to fill the empty spaces in the Hansen trays, but I'm a member of the "better to have it and not need it than need it and not have it" crowd.

Also, I'll usually have the size I need in another drive size.

Like right now - I need some good SAE flare nut wrenches. When I bought the metrics I didn't go ahead and get the SAE set like I normally do. Now that I need them, I can't find a USA set at Sears.
 
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KPSquared

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Wetaskiwin, Alberta, Canada
My set skipped 18mm. . .I had to go buy one. Skipped 20mm. . .had to go buy one. Now I have 2 of everything from 4 mm to 34mm. Even if I only use one once, it's worth it.
 

tbobbo

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May 19, 2011
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Bismarck, ND
I obviously use aome sizes more than others, but i dont have a unused socket in my sets. Maybe my 3/8 20 mm short. I have a 3/8 deep and 1/2 short and deep that are used. 23 mm is dodge 1/2 ton lugnuts. 7mm hex is some dodge break calipers. I used both yesterday. I think my 1/2 sets from gp only skip one number......33 or 29 i cant remember. I use my 23 wrench in place of 7/8 when i dont want to run to my box. (When using my ball joint press)
 

Outlawmws

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I bought basic sets (wrenches and sockets) and only buy what I need if it's missing. (Unless I happen to find it super cheap at a yard sale of something... )

Metric sockets jump from 22mm to 50mm with some other gaps in the smaller sizes.
 

pmohr

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Maryville, TN
By 'hex socket kit' are you referring to bit sockets? If so, 7mm is extremely common for Euro brake caliper bolts, and you'll find some Ford caliper bolts to be 9mm.

11mm (though it might be 7/16) is used on pretty much every GM for the intermediate shaft bolts, and 16mm is again back into the Euro territory (VW and BMW at the least).

I don't see the point of trying to get every single size socket or wrench 'just because', but I'll pick one up if I anticipate a need for it in the foreseeable future. The random things like a 24mm 3/8" deep socket, or a 22mm ratcheting wrench, or a 9mm 12pt 1/2" drive socket, or a 7/64" nut driver, you won't really know you'll need until one of those 'oh ****, wish I had that' moments.
 

ev2mopar

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woodbridge new jersey
I always used to laugh at the 5.5mm sockets. I find that I use it often on fords, along with my 7mm swivel, which is great for ignition coils on the Crown Vics in our police fleet.
I can't recall the size (6.7?) But I had to get the socket for a BMW fuel filter strap a few months back.
I don't forsee that little socket getting much use but, hey, at least I know I did it right.
 

geologist

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Dec 14, 2011
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19/32 and 25/32 - most people laugh, until you happen to need them for an older Ford. Nothing irritates me more than buying what should be a complete tool set only to have sizes skipped. It doesn't matter to me if a 20mm is only used on the ****** switch of a x-58 wadjet grinder, if it exists, I still want the wrench/socket/etc.
 
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greasemonkey44

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9mm are rare but exist
11mm is fairly common on fords iirc(doubles as a 7/16)
16mm is common(euro cars); mostly because it fits a 5/8
20mm is a gm fuel filter; most people use an adjustable

if i need it once i buy it; t60 torx bit, 27mm wrench, allen bit sockets(3/8, 7 and 9 ....all on brake calipers)
it is aggravating when you buy a big socket set and they leave out a 13 or 18......us and euro use 18s alot
 
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SMKS

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I never used my 16 and 18 wrenches until working on my girlfriend's VW. Lots of 16 and 18mm bolts in the suspension.
 

RAYJAY

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UNION DALE PA
I always used to laugh at the 5.5mm sockets. I find that I use it often on fords, along with my 7mm swivel, which is great for ignition coils on the Crown Vics in our police fleet.
I can't recall the size (6.7?) But I had to get the socket for a BMW fuel filter strap a few months back.
I don't forsee that little socket getting much use but, hey, at least I know I did it right.


the 5.5 is super important if working on fords a lot of the inside stuff dash work is 5.5
 

infinite97

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Vancouver, WA
in my industry, the extremely common sizes are 10, 12, 13, 14, 17, 19, 24, 27, 30, 32, 36, 41, 46, 50, 55.

I still bought a complete set, because why not? I know I will never use that 26mm socket, but oh well, it was only a few bucks, right?
 

MN Falcon

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Jan 31, 2010
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Minneapolis MN
Picture3800.jpg


I stole this pict from someone on GJ classifies. I just had to have it because it points out that I am missing all of the tenths of a mm between the even numbers :lol_hitti
 
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G1GRANDEUR

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If you are only working on one vehicle, you could skip some. But otherwise you will end up needing all sizes.
 

Knuckle Buster

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I never used my 16 and 18 wrenches until working on my girlfriend's VW. Lots of 16 and 18mm bolts in the suspension.

18mm is also common on gm rear control arms from late 70's through late 80's. Also found on alot of GM A/C pumps.
 
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Deception

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Jan 15, 2012
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New York
Ive had worm & t bolt clamps that used 7mm & 8mm. Honda rear diff uses a 24mm drain & 23mm fill. You can get away with skipping some sizes, but it ***** when you're in the middle of a job & have to run out to buy another socket.
 

Murphy4570

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West Deptford NJ
Wrench and socket sets that skip sizes are a reason why I loathe most toolsets aimed at the weekend warrior demographic. What use is a socket set that doesn't have 7, 11, 13, 18mm, etc?

I have used every socket size on things, yes there are 9mm bolt heads. As others have said, 5.5mm is used a LOT in Fords. You can substitute a 7/32" socket in a pinch though, as it is the same size (well, 5.55mm). Older Fords used a 7/32" bolt head for TFI modules on distributors, 5.5mm socket works just as well!

The only socket size I can say I have never used is 4mm. Came in my Snappy 1/4" drive sets, never used it.

You would also be surprised at how much fastener heads can "shrink" from rust up here in the rust belt northeast, and finding that a 15mm bolt head has become a 12 or 13mm!!! Knowing where standard sizes fall in relation to metrics comes in handy for this. For example, 1/2" is slightly smaller than 13mm.
 
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WHT

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Jan 17, 2009
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33mm - GM axle nut

To make it more confusing, some GM axle nuts have been revised to 34mm (new supplier) and you now need both sockets or have to replace all of the nuts (GM axle nuts are "use one time" deformed threading).
 

MN Falcon

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Minneapolis MN
I bought a 309pc Craftsman set last fall and the ratcheting wrenches skip several sizes, Oh well, I guess with that type of thing you can't expect a full set just the most common. I was surprised though to see it didn't come with a 20mm 12pt 3/8" drive socket but had both the 19mm and 21mm. I looked to see how much it would cost if I bought a single and could not find this socket as even being available as a Craftsman socket.
 
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dazcapri

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Mar 18, 2011
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durham uk
I never used my 16 and 18 wrenches until working on my girlfriend's VW. Lots of 16 and 18mm bolts in the suspension.

mine were first used on a SEAT (part of VW). My European ****** van has a bolt holding the bottom suspension wishbone on and that's 18mm one side 15mm the other.
 

hunterguy86

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Jan 22, 2012
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Central Texas
11 mm deep well is useful to remove intercooler boots on the duramax.

What I hate is I bought kobalt socket trays and started filling them with kobalt sockets. The 3/8's tray goes all the way to 1 inch but kobalt sockets stop at 7/8's. I figure if I need 15/16 or 1" I'll grab a 1/2" drive buy it just irritates me that they trays have empty holes that take up space in my box.
 

jjjrmx5

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Cincinnati, OH
Wrench and socket sets that skip sizes are a reason why I loathe most tool sets aimed at the weekend warrior demographic. What use is a socket set that doesn't have 7, 11, 13, 18mm, etc?

Thus the difference between professional aimed tool sets vs. the hobbyist or weekend warrior sets and it bugs the **** out of me too though. :)

If Sears offered a full and complete set of sockets like Snap-On does in each set, the price would rise to the point where sales would plummet.

Sears sells sets that covers 75% to80% of what the buyer needs adn then forces him to fill in the rest. Given their price of open stock sockets, Sears makes that sale price up very quickly.

It irritates me more when certain sizes are not even offered , even individually in open stock.

I think that only us ********* tool users or professional techs see the need for complete sizes tool sets and are willing to pay for such, but I'm guessing the common tool buyer is oblivious to it.


What I hate is I bought kobalt socket trays and started filling them with kobalt sockets. The 3/8's tray goes all the way to 1 inch but kobalt sockets stop at 7/8's. I figure if I need 15/16 or 1" I'll grab a 1/2" drive buy it just irritates me that they trays have empty holes that take up space in my box.

LOL.
You do know that there are other socket storage solutions out there don;t you?

That's like buying a house with a big closet that has a 6" long rod to hang clothes on and then has compartments for 200 pairs of shoes in the rest. Does that mean I toss out all of my clothes down to a few shirts and pants and then go but another 175 pairs of shoes to fill things up?
I don't think so.
Storage of anything should be customizable to fit YOUR needs, and not what someone THINKS you need. :)
 
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wafrederick

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15mm is left out sometimes.The mostly used Metric sizes I use are 8mm,10mm,13mm,15mm and 18mm since GM,Chrysler and Ford use these sizes a lot.I have one 20mm wrench just for GM fuel filters and some a/c lines and ran into this for Chrysler powersteeing lines lately on a 2002 Dodge Ram.
36mm is also a commonly used for axle nuts including 30mm and 32mm.
 

RRmech

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Santa Fe, NM
Variation on Murphy's Law..............................................................

The one size they skip, is the one size you need.

Steve
 

Jim C.

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Jan 8, 2010
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20mm is the equivalent of 25/32". I've found original 25/32" nuts and bolt heads on some old Delta woodworking machinery from the 1950s. Initially, I used the 20mm wrench when I came across them. Eventually, I tracked down some wrenches and sockets that were sized on 32nd increments. I personally like to have consecutively sized sockets and wrenches without any gaps if possible. Admittedly there are some sizes that don't see much use. Most of what I like to tinker with is older cars and machines from the 1950s and 1960s, so a lot of my metric tools don't see much use to begin with.

Jim C.
 

Andy Griffith

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33mm - GM axle nut
Great, something else to buy. Don't suppose you can use a big crescent on it either, probably requires a socket?

Edit: just saw the post that says 36mm for 3/4 ton. Hell, why stop there, I might as well buy a set up to 50mm. :)

Had to use the 18mm the other day to get the back seat out of my GM truck.
 
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expfcwintergreen

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Oct 16, 2011
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Of the sizes mentioned by the original poster, 7mm fits the coils on recent 4.6L Ford engines; 16 and 20mm fit the fittings on Chevrolet Astro fuel filters. I can recall what on, but I have used 9 and 11mm wrenches on cars (11mm might fit the bolts on the pan of late model Impala transmissions). After you become familiar with your car, you become familiar with what wrenches you need to work on it specifically, but even then you get surprised on occasion. If you have to work on whatever comes in the door of a shop, I sure wouldn't want to skip sizes in between 6 and 20mm and probably not until I got to about 26mm. I know I don't want to be in the middle of a job and have to stop and get cleaned up to go to Sears to get a wrench I don't have, or even worse, have to wait until the next day because Sears has closed or is out of that size.

I always wished those service manuals like Haynes etc. would have a list of every size you need to work on the cars covered in the manual and the tools you would need for the work done in every section. I have had Helms factory service manuals (which were mostly over my head), and they didn't tell you what sizes or tools you need either. I know I can figure it out, but it would let me know what sizes to keep in a tool bag in the car and what sizes to take with me when I get under a car so I wouldn't have to stop work and go back to the tool box.
 
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j.c.whitney

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Omaha, Ne
Good to know I'm not the only one to obsess over missed sizes in my socket trays.:scared: Knowing full well that I'll never come across or need an oddball size, when you open the drawer it looks like you've lost a socket so all slots must be filled. Otherwise it's just not right.
 

plinker

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From 7mm to 32mm and the only sizes I have not used (or have seen a use for yet) are 23, 25 & 26.

I used a 9mm once, had a Dakota at work with a bad brake line.
7mm is also used on 4mm bolts. 5.5mm is also found in GM's under the dash (Buick heater fan motor), so not just for Ford's anymore.

17 & 19 got replaced with 16 & 18, due to a change in Euro "DIN" standard's.
Some older set's had say 10 to 15 + 17 & 19. And that was mostly all you'd need for your avreage project from what I heard.
 

wafrederick

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I usually use a 5/8'' on a 16mm,fits.Chrysler does use 6mm and 7mm on their smaller factory hose clamps.At work,I have at least 3 18mm,15mm,13mm and 10mm combo wrenches since I use them a lot.I have a 21mm combo wrench too,it gets used sometimes.21mm and 24mm are used on most GM and Chrysler front suspensions when replacing the front struts including rear rear struts on GMs.22mm,I use on lugnuts on 1988 and current GM full size trucks.
 

JMcFly

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If you are only working on one vehicle, you could skip some. But otherwise you will end up needing all sizes.

I stick to Mercedes Benz so I know what sizes I need most. But now with my parents and others asking me to help them out and do routine maintenance on their cars I am needing to get other sizes as well as branch out to SAE. I only have the SAE sizes that came with my 300 piece craftsman set. I think one day I'll invest in more SAE.
 

blackedv

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Jan 20, 2010
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i think i have all of one sae socket set and the only reason i bought it was because i needed a 12 pt 9/16 socket for 2 headbolts on a jeep cherokee lol. Everything i use is metric nowadays but i dont really work on anything older than 1990 and if i do i just use the equivalent metric size and get by most of the time
 

Outlawmws

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Great, something else to buy. Don't suppose you can use a big crescent on it either, probably requires a socket?

Edit: just saw the post that says 36mm for 3/4 ton. Hell, why stop there, I might as well buy a set up to 50mm. :)

Had to use the 18mm the other day to get the back seat out of my GM truck.

yep, Suzuki Samurai front spindle nuts :D
 
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