OT: Science of dropping things

On Sat, 9 Apr 2016 02:49:03 -0400, bitrex Gave us:

Ah... the twilight zone episode. That must have been what happened to Donald Trump's brain. And his followers are even worse.

On Sat, 9 Apr 2016 02:49:03 -0400, bitrex Gave us:

Yes. If you kept looking for them after you found them, you would be recommended for the loony bin.

I am in the same school as yourself, with the advent of SMD I don't look anymore......just reach for the part bin.

Maybe go through the Ignobel prizes? I know they gave a prize to some researchers that studied why and how socks fall of peoples feet, maybe there was a prize for studying things falling to the floor and disappearing into the other corner of the room.

It's called an "apport" and is more common than you might think. Certainly around my workshop it is, anyway.

I think it's covered under some corollary to to Murphy's Law. (And ~1/2 the time you find it right away and forget.)

George H.

Sure.

1. You hear the first hit, but less likely the subsequent bounce and scattering.
2. If you don't follow it quickly by eye, you won't see which way it's bounced. Eye-ear coordination and ambiguity of hearing (your ears are considerably less spacially accurate than you give them credit for).
3. On the bounce, vertical kinetic energy is converted to a random amount of horizontal. Irregular shapes bounce in random directions. Thinking that "it sounded like it bounced over there" is somewhat irrelevant. It also continues rolling or sliding, depending on the surface.
4. You're older, I think? So probably your eyesight alone isn't too great, and even if you can get a clear scan of the floor, spotting small objects is probably difficult (especially if you have no idea where they are, let alone a faulty idea of where they are!).

Idunno... seems likely to me. We generally put way too much confidence in the performance of our senses. This subject alone doesn't seem like something worthy of a paper ... but then, I'm no academic. They are the pros are stretching things out to whole papers. A small-scale controlled study, perhaps?

Tim

--
Seven Transistor Labs, LLC 
Electrical Engineering Consultation and Contract Design 
Website: http://seventransistorlabs.com

If you get a broom and a dustpan, and sweep up around the bench, 99 times out of 100, you'll find the part.

--
Grizzly H.

I have a magnet on an extendable wand for "sweeping" the floor. I'm forever dropping the tiniest of screws :-( ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142   Skype: Contacts Only  |             | 
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  | 
| E-mail Icon at http://www.analog-innovations.com |    1962     | 
              
           The touchstone of liberalism is intolerance

I usually think " Damn ".

I look first, and often shine a flashlight parallel to the floor hoping to see a shadow cast by the dropped part. Then I try the dust pan and it usually works.

Where I used work, the floor was linoleum tiles with a mottled color which made finding dropped parts almost impossible.

Dan

On Sat, 9 Apr 2016 08:15:27 -0500, "Tim Williams" Gave us:

The floors in the lab are granite tiles. Talk about a surface to rebound off of. Drop a screw and you might find it twenty feet away. Especially if the first strike it makes is at a tile transition seam. OMG!

I use to get down with my head practically on the plane of the floor and a flashlight and look for the profile. We keep the floors really well cleaned, so no problem for my head, and easier to see low profile items.

I dropped a tiny M2 metric screw from the end of a set of stand offs I had on a proto board. I stopped looking and grabbed another, but now I have an incomplete set as I never did finish hunting the dropped one down. Major PITA!

And as far as those random bounces go, it almost make us getting hit with another asteroid an inevitability.

That is an excellent point.

On Sat, 09 Apr 2016 07:57:51 -0700, Jim Thompson Gave us:

Does not work for non ferrous items. Doh!

If you have a hard floor, just sweep all the dust bunnies into one pile and the thing will likely be there. That's good to do now and then anyhow. If it's a carpet, especially a deep carpet, forget it.

I always swipe a bunch of small parts from stock when I need one, because there's a good chance I'll lose one before it gets soldered down.

But can you actually lose a cell phone charger?

I have experimantally determined that, if you pick up an 0805 resistor or a SOT23 part N times, and drop it from 12" above the bench, it will land wrong-side up 87% of the time.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics

Parts are getting smaller a lot faster than we're getting older. 1206 resistors used to seem impossibly small. I was soldering some yesterday and they looked gigantic. Even 0805 looks big.

I just got a board with 60 mil high reference designators; they are tiny but beautifully sharp. Yesterday I asked the younger people in production if they would mind my going to 50 mils. They all said no problem, we need magnification to see this stuff already.

Refdes below 100 mils used to be awful, silk screened maybe. Whatever they do now is way better.

Our senses are limited in dealing with electronics. We need a lot of fancy and fun instruments.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics

Pfft, 0603 is average, 0402 and below is where things get tiny.

Not-bragging-bragging about my still young eyes, of course ;-)

Geez, those are bigger than the components.

I've received 25 mil text which was legible, but that's pushing it. I use

30 (6 line width) for most SMTs. 60 (occasionally more) is reserved only for bulky THTs that you're expected to see while plugging things in.

Wouldn't mind a Mantis like you've got, but a loupe is quite handy for inspecting those things my eyes aren't really sharp enough to resolve in the first place.

Tim

--
Seven Transistor Labs, LLC 
Electrical Engineering Consultation and Contract Design 
Website: http://seventransistorlabs.com

My theory is that electronic components have a homing attraction to the place where they were born. If you dump a bucket of parts on the floor, they will tend to land in the direction of their home factory in China, Taiwan, Singapore, Japan, or wherever. Look east, and you will probably find your dropped component. Note: I haven't tested this theory.

Meanwhile, I run a ruler over the carpet. If it hasn't buried itself under the carpet pile, it will bounce into the air, where it can be seen. I also use a flashlight parallel to the floor and look for the shadow. For metallic parts, I have a magnetic nail sweeper: Some things become visible under UV light: For a flat floor, a broom and pan.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

Well, tat is perfectly logical - it ALWAYS is in the last place you looked - by definition. What is spooky is that it is NEVER even near where you heard it drop, _and_ always where you looked at least two to s dozen times before.