Metric Tool Question - Page 1
Forum section: electronics / general

author: Dawn
author_rank: Regular Contributor
timestamp: August 14, 2012, 06:49:20 am
content: Those of you on the other side of the pond might be able to give me an answer to a question that I've had for years and I wonder if it's the same over there.Why do metric sets often skip some combination of 5.5,9,6,12,15, and 18 mm?Maybe there are larger, but in electronics, I've never encountered anything over 14MM. I've heard several explanations as follows:Caps/nuts in those sizes don't exist to ISO or DIN standards.Some of those sizes are duplicated by a very close SAE/Imperial tool and don't need to be included.From experience, this is complete bullshit. Maybe this is true in general mechanics or automotive applications, but I can certainly attest to 9mm and 12mm nuts on Japanese switches and pots. I have even seen Japanese specs call for a 9.5mm which in reality is a near perfect SAE 3/8". Tool companies that cater to the electronics technician crowd here in the states do offer (or used to) continuous sets in 1mm increments with a 5.5mm such as Xcelite,Vaco,and Klein. Some even in full fractional .5mm steps like Xcelite's midget and interchangeable blade sets. I don't buy some of the SAE interchangablility explanations. I've had plenty of 12mm control shaft nuts of that size that a half inch nut driver wouldn't grab on to. Most 3/8" will handle a 9mm switch dress nut. If there's any question on no such thing as a 15mm, somebody hasn't worked on any bicycles. It's rare that a size is skipped in a SAE/Imperial set, even if there's no practical use for a few in most applications. They still include them.Those that sell general automotive/mechanical tool brands usually skip some though in their metric sets. There is no rhyme or reason. Some sets skip a 6mm and 9mm, some only/or 12mm, I have a full spanner set from 4mm-19mm by Proto that just omits 18mm. Many omit the full list above. Some may offer the missing ones independently from their kit or sets, but most do not. Does this only happen here in the states by our manufactuers or does this occur using the same reasoning in metric countries?

author: G7PSK
author_rank: Super Contributor
timestamp: August 14, 2012, 07:21:36 am
content: It is to do with preferred sizes, which seem to differ from one country to another and also one industry to another. In the car industry an 8mm bolt will often have a nut that is12mm across the faces (AF I will use this term but it's not be confused with American fine) In the engineering world virtually all 8mm bolts and nuts will have 13mm AF. The same goes for 10 and 12 mm bolts and nut respectively the car industry will use 16 & 18mm and general engineering 17 & 19 mm The french are particularly fond of unusual size nuts on their cars very often having one size on the bolt and a smaller or bigger size on the nut. The only thing to do is chose a spanner set that runs in 1 mm increments with flank drive rather than edge drive Yuou can tell a flank drive spanner as they have a slight curve on the faces of the sockets and rings and on one face of the open ended.

author: flolic
author_rank: Frequent Contributor
timestamp: August 14, 2012, 07:52:40 am
content: Quote from: Dawn on August 14, 2012, 06:49:20 amBecause over here we try to use standardized nuts and bolts of the first order.Take a look at the table here:http://en.wikipedia.org/wiki/Screw#ISO_metric_screw_threadThat mean that standard and most common wrench sizes are for example: 5.5mm (M3), 7mm (M4), 8mm (M5), 10mm (M6), 13 (M8), 17mm (M10), 19mm (M12), etc.Fine pitch thread nuts and bolts, especially in auto industry often use "intermediate" wrench sizes, 9mm, 11mm, 12mm, 14mm, 15mm, 16mm, 18mm and so on.My French made car has many bolts in 16 and 18mm wrench size...

author: vk6zgo
author_rank: Super Contributor
timestamp: August 14, 2012, 08:02:36 am
content: You can get pretty much all the sizes in Oz--you just have to shop around.There are very cheap Indian sets of spanners which include the very large sizes.1/2" is very near 13mm,9/16" will fit 14mm,and there are quite a few other which are very near equivalents.By the way,I think that "AF" always did mean "across the flats",rather than "American Fine"I'm pretty sure the American fine thread ,at least for cars & the like,is "SAE",& is the same as "UNF.The small US thread which is used in Tektronix & similar equipment is,like BA,an orphan,with no other equivalent.

author: EEMarc
author_rank: Regular Contributor
timestamp: August 14, 2012, 08:29:17 am
content: For some applications, reducing weight is very important. In automotive and especially aviation, reducing weight improves the efficiency. In aviation in particular, weight removed means more capacity for passengers, cargo, and fuel which increase the useful payload and range. They'll choose the fastener that most closely meets or exceeds the specifications required instead of far exceeds by choosing several times larger. Anywhere that weight can be reduced, it is.For non-weight sensitive applications, it is less expensive to buy fewer part numbers each at higher quantities. Bolt length is another factor. It's much easier to deal with one length. It is kind of annoying when you have a part with 3 or more length bolts or screws of the same size and thread pitch but different lengths. It gets really annoying when an application mixes imperial, metric, bolt size, bolt pitch, length. and bolt types all together. This can be found in some automotive applications where parts are designed and manufactured in numerous locations.

author: G7PSK
author_rank: Super Contributor
timestamp: August 14, 2012, 10:28:58 am
content: Quote from: vk6zgo on August 14, 2012, 08:02:36 amI dont know what the quality of spanners from India is like nowadays but some years ago I saw a film where they were srapping old ships on the beach hauling the plate away to cut into strips and then stamping into spanners, which kind of explained why the Indian spanner set that I had bought the year before just folded up on me or the jaws sprung open.

author: Unknown
author_rank: Unknown
timestamp: August 14, 2012, 10:30:48 am
content: Quote from: GK on August 14, 2012, 06:53:52 amAnd they don't even label them so you can avoid getting the left handed ones.

author: flolic
author_rank: Frequent Contributor
timestamp: August 14, 2012, 10:37:21 am
content: Quote from: Uncle Vernon on August 14, 2012, 10:30:48 amWTF!?

author: M. András
author_rank: Super Contributor
timestamp: August 14, 2012, 12:44:24 pm
content: wtf? if you flip that thing it will be the same...

author: mazza85
author_rank: Newbie
timestamp: August 14, 2012, 01:09:02 pm
content: It was an april fools from IKEA...Sent from my phone with Tapatalk

author: robrenz
author_rank: Super Contributor
timestamp: August 14, 2012, 01:48:04 pm
content: Can someone explain the British Whitworth wrench size markings that have nothing to do with actual acros flats dimension?

author: IanB
author_rank: Super Contributor
timestamp: August 14, 2012, 02:21:34 pm
content: Quote from: robrenz on August 14, 2012, 01:48:04 pmI guess it's because the spanner size refers to the screw diameter rather than the across flats dimension. Which is a curious thing. If you are designing and building something the screw diameter would seem to be the much more interesting dimension. On the other hand if you are maintaining something and trying to select the correct tool then the across flats diameter would be more useful. So I guess the preference would depend on whether you are an engineer or a mechanic?

author: icon
author_rank: Regular Contributor
timestamp: August 14, 2012, 05:54:38 pm
content: Quote from: robrenz on August 14, 2012, 01:48:04 pmIt's more complicated than that - the same jaw size does two different jobs, one BSW and the other BSF! Admire my King Dick BSF/BSW socket set; drool over my Imperial spanners! (Made in Germany...)John

author: bingo600
author_rank: Super Contributor
timestamp: August 14, 2012, 06:49:23 pm
content: Get a Bacho Set , Expensive but lasts for a lifetime87+7 - mm & incheshttp://www.justtools.com.au/prod2342.htmS910 Metrichttp://www.justtools.com.au/prod2860.htmS910AF Inches (New) - Seen in PDF catalogCataloghttp://www.euroimpex.com.mk/application/views/media/bahco/Bahco_S_Line_socket_sets.pdf/Bingo

author: SeanB
author_rank: Super Contributor
timestamp: August 14, 2012, 06:58:49 pm
content: I have pretty much every size between 5mm and 32mm, with the biggest being a 65mmAF socket ( one nut uses this) and a whole lot of metric and imperial hex keys. A lot of the hex sizes will accept a Torx driver bit, useful at times, especially for those that are worn a little.Most useful items are a near complete recoil set from M3 to M16, and around a half dozen imperial sizes. With this goes a few tap extractors ( oops.......)along with the metric and imperial taps to break, and a nice bolt extractor set ( actually 2 and one has broken bits) for those bolts that I break off in the tapped hole.

author: nanofrog
author_rank: Super Contributor
timestamp: August 14, 2012, 10:25:24 pm
content: Quote from: bingo600 on August 14, 2012, 06:49:23 pmCOO = Spain?

author: Unknown
author_rank: Unknown
timestamp: August 14, 2012, 11:44:39 pm
content: Handy Workshop Tool referenceDrill PressA tall upright machine useful for suddenly snatching flat metal bar stock out of your hands so that it smacks you in the chest and flings your beer across the room, splattering it against that freshly painted airoplane part you were drying.Wire WheelCleans paint off bolts and then throws them somewhere under the workbench with the speed of light. Also removes fingerprint whole and hard-earned guitar calluses in about the time it takes you to say, “Ouch....”Electric Hand DrillNormally used for spinning pop rivets in their holes until you die of old age.Skil SawPortable cutting device used to make studs too short.PliersUsed to round off bolt heads.Belt SanderAn electric sanding tool commonly used to convert minor touch-up jobs into major refinishing jobs.HacksawOne of a family of cutting tools built on the Ouija board principle. It transforms human energy into a crooked, unpredictable motion, and the more you attempt to influence its course, the more dismal your future becomes.Vise-GripsUsed to round off bolt heads. If nothing else is available, they can also be used to transfer intense welding heat to the palm of your hand.[/td'Oxy-acetylene TorchUsed almost entirely for lighting various flammable objects in your shop on fire. Also handy for igniting the grease inside the wheel hub you want the bearing race out of.Table SawA large stationary power tool commonly used to launch wood projectiles for testing wall integrity.Whitworth SpannersOnce used for working on older British cars and motorcycles, they are now used mainly for impersonating that 9/16" or 1/2" spanner you’ve been searching for, for the last 15 minutes.Hydraulic Floor JackUsed for lowering an automobile to the ground after you have installed your new disk brake pads, trapping the jack handle firmly under the bumper.Band SawA large stationary power saw primarily used to cut good wood into smaller pieces that more easily fit into the trash can after you cut on the inside of the line instead of along the outside.2 by 4Used for levering an automobile upward off a hydraulic jack handle.TweezersA tool for removing wood splinters caused by exceeding the load limits of a 2 by 4PhoneTool for calling your neighbour to see if he has another hydraulic floor jack.Snap-On Gasket ScraperA tool for getting dog**** off your boot after walking cross your neighbours lawn to loan a hydraulic jackE-Z Out Bolt and Stud ExtractorA tool ten times harder than any known drill bit that snaps off in bolt holes you couldn’t use anyway.Two-Ton Engine HoistA tool for testing the tensile strength of fuel lines, earth straps and everything else you forgot to disconnect.Craftsman ½"x16" ScrewdriverA large prybar that inexplicably has an accurately machined screwdriver tip on the end opposite the handle.Phillips ScrewdriverNormally used to stab the lids of old-style paper-and-tin oil cans and splash oil on your shirt; but can also be used, as the name implies, to strip out Phillips screw heads.Straight ScrewdriverA tool for opening paint cans; sometimes used to convert slotted screws into non-removable screws and for butchering your palms.Aviation SnipsSee hacksaw.Trouble LightThe home mechanic’s own tanning booth. Sometimes called a drop light, it is a good source of vitamin D, “the sunshine vitamin,” which is not otherwise found under cars at night. Health benefits aside, its main purpose is to consume 40-watt light bulbs at about the same rate that 105-mm Howitzer shells were used during the first few hours of the Battle of the Bulge. More often in dark than light, so its name is somewhat misleading.Air CompressorA machine that takes energy produced in a coal-burning power plant 200 miles away and transforms it into compressed air that travels by hose to a Chicago Pneumatic impact wrench that grips and rounds of the heads of rusty bolts last over-tightened 58 years ago by someone at ERCO. Also used as a sleep limiting and exercise device when left powered overnight.Pry BarA tool used to crumple the metal surrounding that clip or bracket you needed to remove in order to replace a 50-cent part.Hose CutterA tool used to cut hoses too short.HammerOriginally employed as a weapon of war, the hammer nowadays is used as a kind of divining rod to locate the most expensive parts not far from the object we are trying to hit.Utility KnifeUsed to open and slice through the contents of cardboard cartons delivered to your front door; works particularly well on contents such as seats, human flesh, painted finishes, refund checks, and rubber or plastic parts.Dammit ToolAny handy tool that you grab and throw across the garage while yelling “Damn it!” at the top of your lungs. It is also the next tool that you will need.Prikova ThingRussian term now in common usage for any device requiring tools you do not have available for assembly or disassembly.ExpletiveA balm, usually applied verbally in hindsight, which somehow eases those pains and indignities following our every deficiency in foresight.

author: Unknown
author_rank: Unknown
timestamp: August 14, 2012, 11:47:53 pm
content: Quote from: icon on August 14, 2012, 05:54:38 pmNot just rust and corrosion, but Finest British Rust & Corrosion!!

author: nanofrog
author_rank: Super Contributor
timestamp: August 14, 2012, 11:49:53 pm
content: Got a good laugh out of thatUncle Vernon, thanks.

author: Unknown
author_rank: Unknown
timestamp: August 15, 2012, 12:35:46 am
content: Quote from: nanofrog on August 14, 2012, 10:25:24 pmIt'sBahcoand no COO = Sweden.

author: vk6zgo
author_rank: Super Contributor
timestamp: August 15, 2012, 04:34:22 am
content: Quote from: G7PSK on August 14, 2012, 10:28:58 amThe Indian stuff they sell in Oz is pretty good,except for the occasional one in which the jaws are a bit wide for what size they are supposed to be.I've only noticed it with individual ones,though,the sets are pretty good.Of course,it can happen in the best of families!Many years back,I was very taken with a centre punch I saw at a big machinery place in the city.Made in the UK,it was very" high tech,"complete with a Teflon cover which was supposed to reduce shock to your fingers,or something like that.The shrink pack was emblazoned with the "Duke of Edinburgh's Export Award",& it was about four times the price of the lesser ones.Knowing how tough some of the old Brit stuff was,I bought it,& proudly carried it home.The first time I used it,the tip broke off,& skittered across the floor,never to be seen again!Slightly upset,I went to the local Hardware store,& picked up an El Cheapo Aussie one,rough looking as hell,no Teflon,no shrink wrap no "Jookemburra",in fact no wrapping at all.It looked like they made it,roughly brushed off the metal shavings & chucked it in a box!It lasted me for years,till it went to hide somewhere in the shed with all the 1/2" & 9/16" AF set spanners!

author: ju1ce
author_rank: Regular Contributor
timestamp: August 15, 2012, 06:03:50 am
content: Quote from: Uncle Vernon on August 15, 2012, 12:35:46 amA lot of the new Bahco stuff is made in Spain. The packaging often claims "made in Spain, quality of Sweden". In my opinion they are not of good quality anymore.

author: nanofrog
author_rank: Super Contributor
timestamp: August 15, 2012, 08:27:44 am
content: Quote from: ju1ce on August 15, 2012, 06:03:50 amI wasn't sure if all of Bahco's line (and others) was all made in Spain now after Snap-on Europe bought them up or not.Lindstrom isn't garbage by any means, but the quality has diminished vs. the Swedish made products, and value even more so IMHO, due to shifting the COO from Sweden to Spain. So it seems reasonable to me that this would also be the case with other European brands Snap-on did this with.