mechanikul phenomena that annoy you - Page 1
Forum section: electronics / general

author: CopperCone
author_rank: Super Contributor
timestamp: May 04, 2018, 03:16:34 am
content: What mechanical phenomena is your pet peave?Corrosion?Personally I hate the 'walking' phenomenon that occurs with temperature cycling. It is just completely bizzare that things will end up moving for apparently no reason. This likes to happen with thermal paste. It is insidious.funny failure modes welcome.

author: GlennSprigg
author_rank: Super Contributor
timestamp: May 04, 2018, 03:17:56 pm
content: I'm a technician, and used to live in Darwin, (top of Australia & tropical)Extremely humid, and everything corroded !!!!

author: German_EE
author_rank: Super Contributor
timestamp: May 04, 2018, 04:33:17 pm
content: SqueaksWe can launch a space probe to Pluto but we can't make a car that doesn't have a squeak somewhere. In our case it's the plastic hood that covers the seatbelt roller at the top end, and both the passenger AND driver covers squeak as we move in the seats.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 04, 2018, 04:35:00 pm
content: The extremely small scale, exponential onset of physical contact.It makes simulating Newtonian physics devilishly hard to get right.Tim

author: Mr. Scram
author_rank: Super Contributor
timestamp: May 04, 2018, 04:59:48 pm
content: Quote from: German_EE on May 04, 2018, 04:33:17 pmThey can, but you wouldn't want to pay for it.

author: wraper
author_rank: Unknown
timestamp: May 04, 2018, 05:16:29 pm
content: Quote from: CopperCone on May 04, 2018, 03:16:34 amIt's chemical.

author: Mr. Scram
author_rank: Super Contributor
timestamp: May 04, 2018, 05:21:23 pm
content: If I'd have to pick one it'd be wear and erosion, but I'm actually quite happy with how the universe works. Pretty much every con has a pro. No corrosion, no life for instance.

author: BravoV
author_rank: Super Contributor
timestamp: May 04, 2018, 05:32:29 pm
content: Random image from Google.Busted screw head when unscrewing, made by myself.No, don't get me wrong, I have OCD when it comes to screw driving, ALWAYS use the "right" screw driver tip with the exact size at the screw head type. And always try really hard to maintain it straight and pressed down firmly to the screw head like I can feel the driver was gripping it hard, no loosey metal to metal contact.Still, at some bad conditions where the screw was secured/locked so hard that really difficult to turn, and busted as the driver tip won as its harder.

author: mdijkens
author_rank: Regular Contributor
timestamp: May 04, 2018, 05:39:04 pm
content: My own 'mechanics'I'm almost 50 and- need glasses to see/read anything- my hands are too imprecise to do small stuff- drill a hole very precisely only to find out it's a few mm off- dropping SMD and not able to find them back again- building a case that makes the whole project look clumsy- ....I can develop great projects in my mind and on paper/pc, but when my hands come into play....

author: metrologist
author_rank: Super Contributor
timestamp: May 04, 2018, 05:41:25 pm
content: Quote from: wraper on May 04, 2018, 05:16:29 pmIn that case, I guess mine would have been biological...

author: mdijkens
author_rank: Regular Contributor
timestamp: May 04, 2018, 05:43:04 pm
content: Quote from: BravoV on May 04, 2018, 05:32:29 pmTomorrow I go to my boat (almost 100 miles) for the second weekend just to try getting one bolt loose (I have prepared myself with lots of tools for different methods, but my experience and mechanical qualities are zero)

author: Nominal Animal
author_rank: Super Contributor
timestamp: May 04, 2018, 05:56:43 pm
content: Quote from: German_EE on May 04, 2018, 04:33:17 pmSeconded. I have a toiletry cabinet with metal-to-plastic contact that gets wet that screams like a small rodent everytime you open it, for example when grabbing toothpaste in the morning. And I don't know enough about lubricants to find one that silences it. (Also, cannot replace it, as I'm only a tenant.)

author: Mr. Scram
author_rank: Super Contributor
timestamp: May 04, 2018, 06:18:40 pm
content: Quote from: Nominal Animal on May 04, 2018, 05:56:43 pmAlmost anything should do. Proper oil or something with teflon in it. Thicker stuff is probably better, maybe even grease.You can't replace furniture because you rent?

author: GerryBags
author_rank: Frequent Contributor
timestamp: May 04, 2018, 06:24:57 pm
content: Quote from: mdijkens on May 04, 2018, 05:43:04 pmGet a blowtorch on the bolt. This will make both the bolt and the threads expand which should loosen it. The process is: Heat, hit with a hammer, try to loosen with your wrench. Rinse and repeat. You want the longest wrench you can find, then extend it with a metal pipe over the end or some such. The longer the lever is, the more torque you'll exert on the bolt head.

author: AlienRelics
author_rank: Unknown
timestamp: May 04, 2018, 06:32:45 pm
content: Some college or university did a test and found that a mix of acetone and vegetable oil made a phenomenal penetrating lubricant. Use 30% acetone and it is better than the best commercially available penetrating oil.https://www.engineeringforchange.org/news/how-to-make-penetrating-oil/

author: Mr. Scram
author_rank: Super Contributor
timestamp: May 04, 2018, 06:40:19 pm
content: Quote from: AlienRelics on May 04, 2018, 06:32:45 pmAcetone can mess up plastics and vegetable oil trends to degrade over time. It really depends on the application whether it's a suitable mix.

author: IanB
author_rank: Super Contributor
timestamp: May 04, 2018, 06:44:26 pm
content: Quote from: Mr. Scram on May 04, 2018, 06:40:19 pm...but the job of penetrating oil is usually to loosen up corroded metal to metal screws or bolts so they can be removed. So neither is an issue.

author: mdijkens
author_rank: Regular Contributor
timestamp: May 04, 2018, 06:45:06 pm
content: Quote from: GerryBags on May 04, 2018, 06:24:57 pmYep this time I have a heater and cold-spray with me as well as an impact driver

author: IanB
author_rank: Super Contributor
timestamp: May 04, 2018, 06:45:24 pm
content: Quote from: BravoV on May 04, 2018, 05:32:29 pmAn impact driver is your friend...

author: BravoV
author_rank: Super Contributor
timestamp: May 04, 2018, 06:47:27 pm
content: Quote from: IanB on May 04, 2018, 06:45:24 pmNot always ...

author: Mr. Scram
author_rank: Super Contributor
timestamp: May 04, 2018, 07:01:22 pm
content: Quote from: IanB on May 04, 2018, 06:44:26 pmI took the recipe to be related to the squeaky cabinet, but you're probably right that it wasn't. You can't do much damage to rusty bolts, other than through shear violence.

author: GerryBags
author_rank: Frequent Contributor
timestamp: May 04, 2018, 07:05:54 pm
content: Quote from: Mr. Scram on May 04, 2018, 07:01:22 pmYou should give a dry lubricant like graphite powder. The sell it as a lock lubricant, but it works for plastics too, and won't cause any adverse reactions as it's basically carbon.

author: nali
author_rank: Frequent Contributor
timestamp: May 04, 2018, 07:17:02 pm
content: Quote from: CopperCone on May 04, 2018, 03:16:34 am1. The ability of a small screw, washer or component to travel at least 6ft laterally after having been dropped from a height of about 3ft2. The distance of which is directly proportional to the availability of a replacement part.

author: Seph.b
author_rank: Regular Contributor
timestamp: May 04, 2018, 07:24:54 pm
content: Quote from: nali on May 04, 2018, 07:17:02 pm3. In the direction of the most poorly lite area.

author: BravoV
author_rank: Super Contributor
timestamp: May 04, 2018, 07:31:42 pm
content: Quote from: Seph.b on May 04, 2018, 07:24:54 pm4. And under a tight opening under a heavy & large furniture.

author: Vtile
author_rank: Super Contributor
timestamp: May 04, 2018, 07:53:48 pm
content: If you refer to that Philips type of screw head and bit, then the slip you are faced is the engineered feature of that particular head. The knowledge I recall reading in my journeys of the prehistoric industrial handbooks lalala world is that it was designed to slip out in certain torque to prevent snapped screws in early mass production environments.To be noted that I can not give a reference, it have been a years I did come by that information and I can't recall where (so I don't even not try to find it from thousands of pages of library and/or internet)Quote from: BravoV on May 04, 2018, 05:32:29 pm

author: Cyberdragon
author_rank: Super Contributor
timestamp: May 04, 2018, 07:57:58 pm
content: 1. Stuck fasteners, the smaller the worse EDIT: Yes, that kind of crap! ^2. Unexpected crumbly bits that you think are sturdy till they go crunch (or crumble randomly)3. Things that have come loose that are supposed to be rigid but have bizarre, hidden, or non-obvious means of attachmen

author: BravoV
author_rank: Super Contributor
timestamp: May 04, 2018, 08:08:17 pm
content: Quote from: Vtile on May 04, 2018, 07:53:48 pmSure, I understand what you mean, but that is in academical world, not in real world.Imagine you're tasked to remove that screw, that probably rusted inside too and the rust sort of bonded into the thread insert below, and at the plate like the example photo, and that rusted plate is secured at a really "fragile" old plastic as it aged enough.If you break or even alter that plastic like deforming it, you're screwed and say no paycheck for this month.Now, use heat ? The plastic is not high temp type, use the cool and slick "impact" driver... nah .. you can imagine the rest.

author: Cerebus
author_rank: Super Contributor
timestamp: May 04, 2018, 08:27:23 pm
content: Quote from: GerryBags on May 04, 2018, 07:05:54 pmThe easiest source for graphite is a nice soft pencil, given that most people have one somewhere around the house. Just scribble on the offending surface.One of my mother's cure-alls for sticking and squeaking around the house (especially wood on wood) was to lubricate with paraffin wax by rubbing with a simple white household candle.For plastic or rubber most auto parts stores sell aerosols of a lubricant specifically for rubber and plastic and I've had good results with these.

author: Cerebus
author_rank: Super Contributor
timestamp: May 04, 2018, 08:30:32 pm
content: Quote from: BravoV on May 04, 2018, 07:31:42 pm5. With the cat, dog, or a small child 'helping' you find it.

author: Nominal Animal
author_rank: Super Contributor
timestamp: May 04, 2018, 09:31:35 pm
content: Quote from: Mr. Scram on May 04, 2018, 06:18:40 pmIt's built in to the bathroom, above the sink. The squeaky part is at the bottom, in a recess, which also collects any water that drips down from the mirrored door. (It does have a hole, so it won't sit there.) There is no hinge per se, just a metallic flat bottom, a metallic flange with a hole short distance above, and a thick plastic pin that goes through; the bottom flat contact between the pin (about 10mm diameter) and the painted metallic surface is what squeaks. I could add a bit of grease (something like white vaseline) every week or so, but I just hate to think of a tiny cupboard as a device that needs weekly maintenance to function without annoying noises. I'd like to try Teflon tape, the very slick surface type, if I can find some.Replacing the cupboard is a big hassle, as the walls have a vapor barrier. So, no holes, and if any are made, they must be made to not allow water or vapor ingress into the wall. I also cannot drill any kind of holes to the outer walls, and this being a corner apartment, that's basically half of all walls here, for a roughly similar reason. This is in Finland, with a 50 degree Celsius outside temperature swing between the seasons.[Stupid new building methods with thin films and active air pumps keeping structures dry. The same or better energy efficiency could be had by just using say 500mm of concrete and stone. Not kidding: hundred-year old apartment buildings with high ceilings and thick walls outperform new buildings in their energy efficiency here. But no, we save money, because concrete is so expensive and passé, and use all these new methods that give the house an expected twenty-five-year lifespan. Oops, wrong thread. Sorry!]Quote from: GerryBags on May 04, 2018, 07:05:54 pmGood idea. For my wooden tables and surfaces, I use beeswax and mineral oil mix that I made myself. No, I'm not paranoid; I still eat canned stuff (their lining still contain BPA here). I just like the feel of wood, the ease of maintenance, and the easily repaired but tougher surface than just oiling would yield. And it is easy enough for a silly bugger like me to do.Quote from: Cerebus on May 04, 2018, 08:27:23 pmYup; the most annoying part of the problem is that I don't know exactly what the surfaces are. The paint could be enamel, or it could be acrylic. The plastic could be anything; it mostly feels like cheap ABS. Put the wrong stuff there that strips the paint off, or rusts the metal (whatever it is) underneath, and I need to go through the entire hassle of replacing the cupboard.Which reminds me: You know the old-style paper-backed painters tape? It's absolutely the worst you can use for surfaces, because if you forget it, the glue will leech off from the paper backing, and somehow fuse with the surface itself, and will never ever come off. Brown packing tape does the same. I don't know if the "new-fangled" blue more plasticky type is better in that regard.

author: schmitt trigger
author_rank: Super Contributor
timestamp: May 04, 2018, 09:44:54 pm
content: Quote from: Cerebus on May 04, 2018, 08:30:32 pm6 and to a difficult-to-sweep area, which of course will be filled with lint and dust.

author: Seph.b
author_rank: Regular Contributor
timestamp: May 04, 2018, 09:47:56 pm
content: At least the law of physics are consistent.

author: Cerebus
author_rank: Super Contributor
timestamp: May 04, 2018, 09:49:55 pm
content: Quote from: Seph.b on May 04, 2018, 09:47:56 pmFTFY

author: tautech
author_rank: Super Contributor
timestamp: May 04, 2018, 10:02:25 pm
content: Quote from: schmitt trigger on May 04, 2018, 09:44:54 pm0. Murpys Law !And he'salwayswatching for the most inopportune time to apply it !

author: tautech
author_rank: Super Contributor
timestamp: May 04, 2018, 10:19:29 pm
content: Quote from: BravoV on May 04, 2018, 05:32:29 pmThe good ol' Yankee spanner (hammer) will save you frommostfastener tangles you get into believe it or not.Knowing when and how to apply it is the trick/secret.Most fasteners that have been in place for a period of time form an electrolysis bond between the threads and/or the fastener head and these must broken for straightforward/easy removal.If dissimilar metals, thermal cycling or environmental conditions are likely to affect the fastening then anti-seize compounds need be applied at the time of assembly.Products like Coppercote or equivalent nickel based compounds are your friend.Heat can be of use but again knowing how and when to apply it is the trick/secret.The most useful source is TIG that can be applied very precisely and held on long enough to get good 'soakage' without affecting surrounding parts unduly.My #1 pet hate is flush snapped studs/bolts, especially when they're Grade 8 or harder.#2 broken conductors due to poor strain/bending relief.

author: Seph.b
author_rank: Regular Contributor
timestamp: May 04, 2018, 10:39:12 pm
content: Quote from: tautech on May 04, 2018, 10:19:29 pmI specify very explicitly in the install instructions I write things like "If you need to bend the ring terminal connections only do so once." Still happens, but at least I can feel better about myself for warning them.Related pet peeve is people who crimp connectors twice. I can't seem to convince them that they are bowing the metal away from the wire with the second crimp. I mean the connectors are like a cent each, if the first crimp doesn't seem good just grab a new connector and redo it.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 05, 2018, 12:30:44 am
content: Quote from: AlienRelics on May 04, 2018, 06:32:45 pmSounds like something for AvE to test and get further data on!

author: Cerebus
author_rank: Super Contributor
timestamp: May 05, 2018, 01:50:50 am
content: Quote from: NiHaoMike on May 05, 2018, 12:30:44 amYou've missed the boat (almost, he tried an acetone and ATF mixture):

author: vk6zgo
author_rank: Super Contributor
timestamp: May 05, 2018, 03:04:12 am
content: Why, oh why, do spectacle makers use screws as hinge pins?A moment's reflection would make it obvious that, over time, they will come unstuck, fall to the floor & skitter away, never to be found.Another "pet hate" is hinges & latches that rely upon the flexibility & resilience of plastic.They work for a little while, then all the "flex" disappears.

author: German_EE
author_rank: Super Contributor
timestamp: May 05, 2018, 07:49:01 am
content: We can also add manufacturers who use half a dozen different sizes of screw when assembling their product, I'm looking at you Elecraft and Apple. Find one or two useful screw sizes then design around them, please.

author: TerraHertz
author_rank: Super Contributor
timestamp: May 05, 2018, 08:29:16 am
content: I have a long beard. From the frequency with which the roller wheel axles of my chair get jammed up with beard hair, you'd think I was a Wookiee, or Yeti or something.The pain of clearing out small fractured pieces of 0.5mm lead from the clutch mechanism of engineer's pencils.Cleaning small drops of dried food liquids off keyboards and LCD screens.How so many varieties of range selection knobs and pots go stiff as the original grease ages.In any volume of space containing both test leads and pliers/cutters, pulling on the test leads will ALWAYS involve the pliers and leads getting in some kind of kinky sexual entanglement. Sometimes resulting in cut leads.Letting go of the loose end of wire on a reel. Resulting in many, many turns of the wire unwinding enough to be loose and entangled.The dust that accumulates behind desk monitors.Shifter spanners that do more shifting than spannering. Always too loose or too tight for the nut.Oil creep.Having to regularly clean up machining swarf off everything in the vicinity of the lathe/mill/drill press.Walking sharp bits of swarf into other rooms on your shoes, then treading on them in bare feet.PC case bits that start vibrating noisily in sync with the beat between different hard disk spin rates.Mains cord tangles.Trying to find the right allen key for some obscure size grub screw, in a big box of loose allen keys. (I'm actually pretty good at this.)Wanting to use metric thread bolts for a project, but finding you only have the right length in Imperial, and you want to use those buggers up and be done with them. But then having to buy more to match the ones you already used.The way workshops and storage space are always some small fraction of a desirable size.

author: Cyberdragon
author_rank: Super Contributor
timestamp: May 05, 2018, 12:55:47 pm
content: QuoteThen they jam and strip...

author: Cerebus
author_rank: Super Contributor
timestamp: May 05, 2018, 01:35:45 pm
content: Quote from: vk6zgo on May 05, 2018, 03:04:12 amKnown in the trade as a "living hinge". And, no, I don't know why.

author: Iwanushka
author_rank: Frequent Contributor
timestamp: May 05, 2018, 03:47:22 pm
content: Quote from: GerryBags on May 04, 2018, 07:05:54 pmBest option for hinges in humid environment or when in contact with water is so called Solidol grease you can even use that thing underwater, no idea if you can still buy it, I'm still using USSR stock.

author: Gregg
author_rank: Super Contributor
timestamp: May 05, 2018, 05:18:40 pm
content: Plastics that lose their plasticity prematurely that crack, break and crumble; usually at the most inopportune time.

author: ucanel
author_rank: Regular Contributor
timestamp: May 05, 2018, 05:54:26 pm
content: Quote from: wraper on May 04, 2018, 05:16:29 pmMaybe quantum mechanical?

author: Mr. Scram
author_rank: Super Contributor
timestamp: May 05, 2018, 05:58:39 pm
content: Chemistry is just mechanical physics on a tiny scale.

author: GreyWoolfe
author_rank: Unknown
timestamp: May 05, 2018, 09:52:33 pm
content: Quote from: nali on May 04, 2018, 07:17:02 pm6 ft? Not even close. I think they go out the door of the office, across the yard and into the neighbor's yard.

author: Cerebus
author_rank: Super Contributor
timestamp: May 06, 2018, 12:19:04 am
content: Quote from: blueskull on May 05, 2018, 11:47:59 pmNot exactly amechanical phenomenonthough, eh?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 06, 2018, 12:53:59 am
content: Alright, spring constant and mass.Both are consequences of the finiteness of our world!Tim

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: May 06, 2018, 12:56:16 am
content: High efficiency/low flush volume toilets that take 3 or more flushes to do what one flush of an "inefficient" toilet would do.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 06, 2018, 01:57:46 am
content: Quote from: JohnnyMalaria on May 06, 2018, 12:56:16 amYou just need a poop knife!Tim

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: May 06, 2018, 03:09:20 am
content: Well, I didn't want to go thereI used to have a poo-stick. The best fix is a large pan of water poured into the bowl from a great height - like the old style cisterns mounted near the ceiling. Lovely.

author: TerraHertz
author_rank: Super Contributor
timestamp: May 06, 2018, 08:12:26 am
content: Today: Daughter (26) + jackhammer + copper water pipe.She's digging a garden area in hard soil, to put down pavers. The neighbors lent her an electric jackhammer. I showed her where the pipe is, by carefully hand digging down to it at a couple of points in her excavation area. She still managed to hit it.I was in the kitchen making myself lunch, watching her when she hit it. Pretty comical, wish I'd been video recording.Didn't take long to fix, and the comedy made up for the nuisance.

author: TerraHertz
author_rank: Super Contributor
timestamp: May 08, 2018, 12:03:15 am
content: Glaring spelling errors, capitalization fails, apostrophe errors and grammatical goofs,in thread titles.Seriously, how hard is it to get one short line right?(It's mechanical, because someone typed it.)

author: Cerebus
author_rank: Super Contributor
timestamp: May 08, 2018, 01:07:27 am
content: Quote from: TerraHertz on May 08, 2018, 12:03:15 amIt's mechanical because you'll just be banging your head against the wall if you try and get people to fix it.I can tolerate the odd spelling mistake, the odd grammatical error, even the odd greengrocer's apostrophe (even though I have, on occasion, advocated for the death penalty for the same). What concerns me is the number of native English speakers who flout the most basic English syntactic and grammatical rules like capital letters for the start of sentences and proper nouns, a full stop at the end of a sentence, paragraphs, complete sentences and so on. How the heck can people like that be trusted with MHz, kHz, mHz, K, S*and s?*Personally I have always been a great fan of the mho, but I was never that fond of the ℧ notation for it - too hard to read and very dependent on having the right font.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 08, 2018, 03:20:59 am
content: One space or two after an end-of-sentence period?Tim

author: Cerebus
author_rank: Super Contributor
timestamp: May 08, 2018, 03:37:33 am
content: Quote from: T3sl4co1l on May 08, 2018, 03:20:59 amTyping, on an (electro-)mechanical typewriter - two. Manually stacking letterpress type in a forme - en space between words, em space between sentences. Anywhere else, let the layout software/people sort it out - what are we paying the art desk for anyway?

author: TerraHertz
author_rank: Super Contributor
timestamp: May 08, 2018, 04:29:11 am
content: Quote from: T3sl4co1l on May 08, 2018, 03:20:59 amYou forgot the Asian variant in English .One spacebeforethe period .Or just none like this(That was painful to type.)It's mystifying how anyone trying to pick up a language could fail to notice that difference. But then, I can't understand how anyone could recognize thousands of ideograms either. So what would I know?

author: Nominal Animal
author_rank: Super Contributor
timestamp: May 08, 2018, 04:55:01 am
content: shouldn't of

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 08, 2018, 06:17:32 am
content: There are a few people who consistently punctuate with space . Like this . Does anyone know what 's up with that ?Tim

author: BrianHG
author_rank: Super Contributor
timestamp: May 08, 2018, 07:14:23 am
content: That bloody 60hz/120hz hum permeating my entire apartment because every fan and air-conditioner/heat pump is audible through the frame of the building somehow perfectly focused in my bedroom right at the mattress into my ears driving me nuts every single night and I can never get a decent sleep unless there is a 12 hour blackout through the night.

author: Mr. Scram
author_rank: Super Contributor
timestamp: May 08, 2018, 07:20:44 am
content: Quote from: BrianHG on May 08, 2018, 07:14:23 amYou need a mechanically decoupled bed.

author: Mr. Scram
author_rank: Super Contributor
timestamp: May 08, 2018, 07:35:22 am
content: Quote from: T3sl4co1l on May 08, 2018, 06:17:32 amLook at TerraHertz's post.

author: bitwelder
author_rank: Super Contributor
timestamp: May 08, 2018, 09:06:40 am
content: Quote from: T3sl4co1l on May 08, 2018, 03:20:59 amA tab

author: Psi
author_rank: Super Contributor
timestamp: May 08, 2018, 09:35:56 am
content: I find that phenomena weird where you open up something really old that's made of plastic (usually white plastic) and you get those odd looking spider patterns in the plastic, hard to explain if you've not seen it before. But im guessing you know what i mean.You'd often see it on the inside walls of a white outdoor plastic industrial enclosure.It almost looks organic, but ive never found a reference to what it is.

author: Mr. Scram
author_rank: Super Contributor
timestamp: May 08, 2018, 10:07:05 am
content: Quote from: Psi on May 08, 2018, 09:35:56 amPlastic kraken. I mean cracking. It's basically what you see in porcelain too.

author: TerraHertz
author_rank: Super Contributor
timestamp: May 08, 2018, 10:29:01 am
content: Quote from: T3sl4co1l on May 08, 2018, 06:17:32 amAre they native Asian speakers?My best guess is that since written Chinese does not have the concept of punctuation AT ALL, they struggle with grasping how to use it.But I'd really like to hear an explanation from someone who does that.

author: TerraHertz
author_rank: Super Contributor
timestamp: May 08, 2018, 10:39:42 am
content: Quote from: Psi on May 08, 2018, 09:35:56 amYou mean the patterns of dark lines? The ones that rub off easily with a damp cloth?And they tend to radiate from the injection molding inlet points.I know what it is.Plastic is an electrical insulator. But that doesn't mean it can't contain electrostatic charges. You know it can, by observing what happens when you rub plastic surfaces. But there can be charge trapped in the bulk material too.When the plastic is molten, and going through in injection molding machine, the plastic surface can pick up charge, And then that material gets flowed into the interior, since it's molten. Areas of varying charge imbalance get carried into the mold with the molten plastic, which then freezes solid. Result - there are 'liquid flow lines' of static charges trapped inside the plastic.These produce electrostatic fields on the surface of the plastic object. Small dust particles in air near the plastic surface develop charge polarization due to that field, and are attracted to points on the plastic surface with the highest charge. Gradually building up that spider web of dark lines. You're looking at the charge pattern that was frozen into the plastic during manufacture.

author: Urs42
author_rank: Unknown
timestamp: May 08, 2018, 11:04:44 am
content: gravity.

author: Psi
author_rank: Super Contributor
timestamp: May 08, 2018, 12:19:13 pm
content: Quote from: TerraHertz on May 08, 2018, 10:39:42 amAWESOME++Great to get a solid answer on that, and it makes total sense.

author: BillB
author_rank: Unknown
timestamp: May 08, 2018, 12:59:19 pm
content: Since this has turned into a general annoyances thread, and while I can't top low-flow toilets, I'd like to nominate statically-charged Styrofoam packing peanuts.Does wanting to fill up a bag with those things and use it to bludgeon to death (albeit very slowly) the shipper who uses them make me a bad person?

author: Rerouter
author_rank: Super Contributor
timestamp: May 08, 2018, 01:16:59 pm
content: The ability that screws, washers and nuts can quickly become magnetised by the act of undoing them,So many times I have dropped a screw, and its vanished, taken the surrounding 3x3m area to mid level clean room standards with how far i am going to find it,finally give up, turn my head, and there it is stuck in some impossible location to the side or underside of a nearby device,And drilling through thick aluminium sheet, It just loves sticking to certain drill platings, so every hole you need to brush down the flutes to get off the semi-welded chunks, which blunts the drill more..

author: jolshefsky
author_rank: Regular Contributor
timestamp: May 08, 2018, 01:26:19 pm
content: Quote from: JohnnyMalaria on May 06, 2018, 12:56:16 amThe phrase you're looking for is "toilets of poor design." I replaced a horrid 5-liter-per-flush toilet that would only swirl things around in the bowl with an efficient one (1.6lpf) that has NEVER needed two flushes in 15 years.

author: b_force
author_rank: Super Contributor
timestamp: May 08, 2018, 01:37:15 pm
content: Which annoys me?Of course NON.Otherwise there wouldn't be a challenge for me as an engineer!Embrace your enemies!

author: GreyWoolfe
author_rank: Unknown
timestamp: May 08, 2018, 01:40:33 pm
content: Quote from: jolshefsky on May 08, 2018, 01:26:19 pmWe have a Kohler high efficiency toilet in the master bath, the one in the old commercials that could flush anything. On a good or bad day depending on perspective, I can solidly block it, needing a plunger. However, I was able to do the same to the old 'inefficient' toilet also.

author: Cerebus
author_rank: Super Contributor
timestamp: May 08, 2018, 02:08:16 pm
content: Quote from: BillB on May 08, 2018, 12:59:19 pmI'd like to un-nominate statically-charged Styrofoam packing peanuts because of the hilarity that ensues after the cat gets into them and goes crazy trying to get them off itself.

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: May 08, 2018, 02:45:03 pm
content: Quote from: Urs42 on May 08, 2018, 11:04:44 amDon't ask me why but this got me thinking. If we lived in space in zero g, what everyday phrases would become non-sensical?"WhyWhen I realized there was no gravity,I nearly fell off my chair."

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 08, 2018, 07:17:39 pm
content: Quote from: TerraHertz on May 08, 2018, 10:29:01 amMaybe. But I know a guy who's probably never been out of the country who does that. I forget what he said, something about line workers and clarity?? It's been a while...Tim

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 08, 2018, 07:24:24 pm
content: Quote from: JohnnyMalaria on May 08, 2018, 02:45:03 pmTim

author: jdraughn
author_rank: Regular Contributor
timestamp: May 08, 2018, 08:51:45 pm
content: Hitting my hand with a hammer, pinching a finger with pliers, ect..

author: chris_leyson
author_rank: Super Contributor
timestamp: May 08, 2018, 09:22:16 pm
content: Water hammer. I used to have a gas fired central heating boiler that would sometimes go over its 4 Bar pressure limit. The release valve would open letting some water out and then the pressure wave would travel down the main flow or return pipes bounce back and kick the release valve again. When it went over pressure the valve would oscillate at a few Hz. Because I live in a bungalow the heating flow and return pipes are installed in the roof space and when this all goes off at 4 o'clock in the morning it's better than any alarm clockAs toilets have been mentioned then it has to be the siphonic flush with a flapper-valve. They are a real pain to replace because sometimes you have to remove the entire cistern to get at the fittings and the cheap plastic flap valves sometimes only last a year. The newer designs with concentric valve mechanisms are much better.Compression joints on microbore pipes because they only seem to work only once because the pipe gets necked down.Runout on cheap Dremmel like tools...oops there go another expensive carbide drill !Last but not least, crossed threads.

author: Mr. Scram
author_rank: Super Contributor
timestamp: May 09, 2018, 12:26:36 am
content: Cross threads are the professional's Loctite.

author: TerraHertz
author_rank: Super Contributor
timestamp: May 09, 2018, 12:59:14 am
content: Quote from: Rerouter on May 08, 2018, 01:16:59 pmSo use a cutting fluid. Almost anything will do - oil, WD40, kerosene, actual commercial cutting fluid... They all will stop the aluminium sticking to the drill bit. Only a drop or two needed as you begin drilling. More as you go, for really deep holes.Also, when you do get swarf adhering in the drill flutes, don't use a steel wire brush. Just a sharp pointed scriber, running down the bottom of the flute to pry up the swarf. Works better, and doesn't touch the drill cutting edges.You shouldn't use a steel wire brush on ANY cutting tool. Definitely not on files. For those, use a brass wire brush.And btw, squirting a little kerosene on a file before using it on aluminium, will make an amazing improvement. The file doesn't clog. Loose metal dust can be easily brushed off with the brass wire brush. You get a smooth filed aluminium surface, no galling.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 09, 2018, 05:40:46 am
content: Quote from: chris_leyson on May 08, 2018, 09:22:16 pmIn my experience, compression fittings on copper tubing are no good because the copper transfers stress to the seal and causes it to leak. On PEX, it works well.

author: ikrase
author_rank: Regular Contributor
timestamp: May 09, 2018, 06:00:35 am
content: - Connectors that wear out.- Connectors (commonly D-sub) that end up being much less physically robust than they seem to be -- commonly, a D-sub connector is assembled with diecast metal shells, jack screws, and a hefty cable gland, but a bit too much side load easily ruins it. I think one of the VGA DB-15HD connectors at a conference room projector at my job was ruined by someone who doesn't even work here.- Vibration.- Bad strain reliefs.

author: G7PSK
author_rank: Super Contributor
timestamp: May 09, 2018, 03:34:50 pm
content: Plastic display packaging that requires industrial power tools to open.

author: Gyro
author_rank: Super Contributor
timestamp: May 09, 2018, 06:07:45 pm
content: Quote from: chris_leyson on May 08, 2018, 09:22:16 pmYou want the Dudley Duoflush!You can replace the diaphragm without having to remove it from bottom of the cistern, saves loads of effort. Flap valves are the spawn of the Devil - more expensive spares too.http://www.thomasdudley.co.uk/bathroom/cistern-components/turbo-88-syphon.html(No affiliation)

author: chris_leyson
author_rank: Super Contributor
timestamp: May 09, 2018, 06:24:58 pm
content: Thanks Gyro, it's nice to see some common sense design for a change. The one I have fitted was from Wickes and comes in two parts, the outlet valve and a concentric float, not sure if the outlet valve mechanism can be replaced without taking the cistern off the wall but it's been in service for nearly two years without a problem.

author: TerraHertz
author_rank: Super Contributor
timestamp: May 10, 2018, 10:31:39 am
content: Screw threads of different standards, that *almost* fit each other. Some examples I know to be wary of:* M5 vs UNF #10Same pitch, M5 dia very slightly bigger than #10.UNF #10 screw fits M5 nut.M5 screw NOT QUITE fits #10 nut.* M6 vs 0 BAAlmost perfect fit. 0BA screws very tight fit or won't go into M6 nuts.* 1/4" BSW nearly matches a UNC #??* What is the thread that is very close to an M3, but a tiny bit smaller? Not an M2.5.* 5/32"BSW vs UNF #8Same pitch, UNF #8 slightly bigger dia, but can force into 5/32" nut.(Australian cupboard handle screws are 5/32" BSW.)

author: Nominal Animal
author_rank: Super Contributor
timestamp: May 10, 2018, 12:53:14 pm
content: Quote from: TerraHertz on May 10, 2018, 10:31:39 am#4-48.M3 has 3mm major diameter and 0.5mm pitch, #4-48 (UNF #4) has 2.8448mm major diameter and 0.5292mm pitch.If there was such a thing as #4.47-50.8, it would match M3 exactly.

author: Cerebus
author_rank: Super Contributor
timestamp: May 10, 2018, 02:13:42 pm
content: Quote from: TerraHertz on May 10, 2018, 10:31:39 amOh lordy yes! One of the very few inanimate things that can, on a bad day, reduce me to a hissing, spitting rage. Hate, hate, hate, hate, hate, hate, hate, hate, hate, hate, ... (Cont'd page 72)Quote4-40 UNC???

author: German_EE
author_rank: Super Contributor
timestamp: May 10, 2018, 02:35:18 pm
content: Regarding the metric/imperial thing. All of my component drawers are red except the one holding non-metric hardware, that one is blue. All of the non-metric tools such as Allen keys and drills have some blue heatshrink on them somewhere.Apart from some controls such as ten-turn potentiometers that have quarter inch shafts I never EVER mix metric and non-metric hardware in the same project. Any non-metric fitting is marked with a dab of blue loctite.

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: May 10, 2018, 05:09:23 pm
content: I have a metric brain and live in a non-metric country.Actually, I consider myself bi-metric. For anything longer than an inch, I tend to use feet, miles. Rarely yards, though. Same with weights. Pounds, stone, ton(ne)s, grams, milligrams etc. Less than an inch, it's centimeters, millimeters, microns, nanometers. More frustrating is growing up with Imperial and then moving to the US with its screwed up version

author: BravoV
author_rank: Super Contributor
timestamp: May 10, 2018, 05:53:01 pm
content: Sorta mechanical, but when watching video, but better watch this to get my gripe.https://youtu.be/AqHZJe6306k

author: Cyberdragon
author_rank: Super Contributor
timestamp: May 10, 2018, 06:34:27 pm
content: Quote from: Cerebus on May 10, 2018, 02:13:42 pmImagine using one of those nonadjustable drivers and somehow having it cross thread all the way down straight. You'd never know it until you try to remove it later and have "fun times".EDIT: I spent like 20 minutes on a stupid wrong look-alike screw once. I was starting to think the above had happened and stripped it somehow. Luckily I figured it out before trying to use a driver or the above would have actually happened.EDIT2: In scenarios where you have a stuck grub screw that looks in perfect shape but strips when you try to remove it, is that caused by cross threading?

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: May 10, 2018, 06:55:35 pm
content: Quote from: BravoV on May 10, 2018, 05:53:01 pmOh yes. I didn't have to watch to know what it is but I did anyway. What are people thinking!!!!!!!!!!!!?

author: BravoV
author_rank: Super Contributor
timestamp: May 10, 2018, 06:59:49 pm
content: Quote from: JohnnyMalaria on May 10, 2018, 06:55:35 pmHave you watch thru the end ? Especially the ending.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 10, 2018, 07:12:16 pm
content: Quote from: Cyberdragon on May 10, 2018, 06:34:27 pmImagine if it were stainless steel, clean (degreased, no antiseize)!QuoteReminds me of sometimes finding a double-leaded screw in a box of screws from the hardware store. Fish around in the box, pick out a screw, try putting a nut on it... nope, cross threaded? Try again, hold it on there, back off the screw a bit, surely it'll line itself up...still no? What's wrong with this... oh.Tim

author: CopperCone
author_rank: Super Contributor
timestamp: May 11, 2018, 01:29:01 am
content: Quote from: JohnnyMalaria on May 06, 2018, 12:56:16 amExcalibur the turd smiter (coat hanger taped to stick )

author: TerraHertz
author_rank: Super Contributor
timestamp: May 14, 2018, 01:11:20 am
content: IDCs. Insulation Displacement Connectors. Most unreliable connectors in existence. (Closely followed by poor quality IC sockets, with tin-plated IC legs.) How many times prior to SATA did I have to replace bad IDE and floppy drive cables?The first pic is me finally getting around to sifting through two huge boxes of IDC cables from PC motherboard kits. In the early 2000s I worked at a place that used PC motherboards in a commercial product. They didn't use most of the cables that came with the motherboards, so accumulated a vast number of them. When they decided to throw them all in the dumpster, I intercepted. The boxes then sat around for many years, being a bulky, barely liftable nuisance. This year in a cleanup I moved them to a pile of stuff outside under a sheet, all to be sorted to keep vs toss.I kept about 10% of the cables, for future historical-PC maintenance. The rest are gone to the recyclers. About $70 worth, ha ha. Just glad to be rid of them.Among the 'keep' pile, a box of 10-pin connectors with cable. Useful for use with some USB flash chip programmers that just arrived in the mail. For laptop BIOS unlocking experiments.

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: May 14, 2018, 02:33:16 am
content: The thing about 'keep' boxes is that they ultimately become 'pointless crap' boxes. Looks like in your first photo that you are getting ready to bury them...

author: CopperCone
author_rank: Super Contributor
timestamp: May 16, 2018, 02:15:09 am
content: making a list of things to do with all your garbage helps, but holy shit you look at it and you go likeso much easier to accumulate shit then to use it. I am still on a 10 year backlog.Sometimes I feel that the practice causes intense mental stress, particularly when its not sorted right.But sometimes I think about it, and like the effort that goes into sorting one junk screw box, you feel completely wired afterwords, you spent 3 hours doing it, and you calculated you made around 5 dollars an hour............................Then you think, fuck, why not just buy stainless screws when I need them? Why do I have galvinized zinc??Whats worse is welding stock, like keeping pieces of angle iron, bits of sheet, studs, etc.It's kind of nice to have but its a complete cunt to maintain, because of rust. Is it even worth spraying with wd40? Is it worth the wire brush time, angle grinder accessories, etc to clean up?I almost feel like some of us can benefit from hiring fucking stockpile managers.I have a box of component cables that are making me downright psychotic.

author: TerraHertz
author_rank: Super Contributor
timestamp: May 16, 2018, 04:49:51 am
content: Quote from: CopperCone on May 16, 2018, 02:15:09 amI don't worry about it. Mostly don't bother sorting 'parts junk' much. But when I do, I treat it as a relaxing interval of 'basketweaving'.QuoteHa ha, made worse when like me you have an *amazing* wholesale warehouse of high quality fasteners very close by, and their stainless steel stuff is still cheaper even in bulk packs, than a few crappy iron bolts from the hardware store (that is further away.) I've often considered throwing out my entire stock of iron fasteners (various platings) and switching entirely to stainless. For some sizes and purposes I pretty much have. But ironically, it makes me feel guilty to use 'luxury' screws on plain projects. Weird huh? So I keep the boxes and boxes of old fasteners.At least I very rarely buy plain steel ones anymore.QuoteWrong approach. Keep an open top tin with some heavy oil, and a rag soaking in it. Run the rag over all bare steel surfaces. Nearly permanent rust prevention. WD40 evaporates, protects for less than a year.Also stack the bars end up in a vertical rack, helps keep dust off the surfaces.I have bar stock I bought 30 years ago, still not rusty.QuoteAt last, an actually worthy application for AI! Forget your self-driving cars, and Internet machine-learning censors. We wantjunkstockpile manager robots!Asimov's three laws of hoarding:1. A robot may not throw any potentially useful shit out, or through inaction allow those things to become lost/buried/inaccessible, or ruined by exposure to weather.2. A robot must obey orders given it by human beings except where such orders would conflict with the First Law.Robots must be trained in diplomacy, to deal with instances of wives instructing them to throw things out.3. A robot must protect its own existence as long as such protection does not conflict with the First or Second Law.Getting crushed under collapsed piles of junk is to be avoided if at all possible. Ditto getting dismantled by wives.Edit to add:Something else I hate.The very moment that you get your hands covered in filthy black grease, your nose starts to itch ferociously.I just replaced a broken gear change lever in my best power drill, and had that effect the whole time.