The Smell of Molten Projects in the Morning
Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.
Who’d’a thunk it?
Got up this morning, looked out the kitchen window, and there stands a turkey on the patio!
They’ve been edging closer and closer for the last week or so; we think the snow cover is making the seeds under the feeder look more attractive. As nearly as we can tell, though, they have yet to venture across the patio to the feeder: no tracks in the snow.
What would be really impressive: a row of turkeys lined up on the patio railing, just like they do on our neighbor’s split-rail wooden fence.
Speaking of things that don’t work, these header pins from my stash have developed some sort of rot. They’re genuine Brand Name pins, albeit a few decades old, and have been stored in the original bag in various basements along the way.
What’s supposed to happen: you touch a pin with a soldering iron and some solder, the solder melts and wets the pin. If the pin is in a circuit board at the time, the solder bonds it to the pad surrounding the hole. Nothing exciting here, except that when I tried to use these pin headers, that didn’t happen.
The symptom is that the headers are unsolderable: the solder doesn’t wet the pins.
The detail view shows what does go on. When I touch a the pin, the original solder plating scoots out of the way, exposing the underlying metal (or whatever it is). Neither tin-lead nor tin-silver solder wets the surface, so the pin can’t be soldered.
The flux forms a layer over the new surface and doesn’t do its usual job of cleaning the metal. Scraping the pin clean doesn’t seem to help, either. In fact, nothing helps: that whole bag of headers is a dead loss.
I’m sure these things worked when they were fresh, but that was a long time ago. I’m not sure what sort of change could occur underneath the original solder plating.
So I picked up some new headers with what passes for gold plating these days and they work fine.
The pix come from my pocket camera on the binocular microscope, using my homebrew adapter.
Not that anybody pays attention to these things, but NOAA’s N-Prime earth observatory had a successful launch today.
There’s a bit of backstory to this bird: Lockheed-Martin manged to drop the satellite during the final phase of its assembly, causing all manner of damage. Basically, they forgot to bolt the booster adapter down before trying to tilt the satellite over.
It seems L-M ate the rebuild costs, which was a nice gesture on their part.
I wrote about the event in my Dr Dobb’s Journal column some years back, in the context of how we do error checking in our projects. Bottom line: no matter how good you think your development process might be, alas, you’ll always miss something. The trick is to miss only small problems, not project-killers.
Now, if only the bird works correctly…
This flotsam recently washed over the railing. I added the bold highlight:
Ladies and Gentleman.
In order to have your company inserted into the registry of World Businesses for 2009/2010, please print, complete and return the enclosed form (PDF file) to the following address:
WORLD BUSINESS GUIDE
P.O. Box 2021
3500 GA Utrecht
The Netherlandsregister@ — .biz
FAX: ++31 — — 8107Updating is free of charge
Treating the attached PDF with the same casual nonchalance I use with any lump of high-level radioactive waste, I opened it in The GIMP (to strip any interesting PDF malware) and found an ordinary printable PDF form.
Surprisingly, it didn’t have any slots for charge card or bank account info, but, down at the bottom, there’s a dense block of fine print.
I ran it through pdftotext to get the raw text and here’s the kick in the head, boldified for your reading convenience.
THE SIGNING OF THIS DOCUMENT REPRESENTS THE ACCEPTANCE OF THE FOLLOWING CONDITIONS AND THE CONDITIONS STATED IN “THE TERMS AND CONDITIONS FOR INSERTION” ON WEBPAGE: WWW.WORLD-BUSINESSGUIDE.COM. THE SIGNING IS LEGALLY BINDING AND GIVES YOU THE RIGHT OF AN INSERTION IN THE ONLINE DATA BASE OF THE WORLD BUSINESS GUIDE, WHICH CAN BE ACCESSED VIA THE INTERNET. A CD ROM WITH WORLDWIDE BUSINESSES IS GRANTED, ALL IN ACCORDANCE WITH THE CONTRACT CONDITIONS STATED IN “THE TERMS AND CONDITIONS FOR INSERTION” ON WEBPAGE: WWW.WORLDBUSINESSGUIDE.COM. THE VALIDATION TIME OF THE CONTRACT IS THREE YEARS AND STARTS ON THE EIGHTH DAY AFTER SIGNING THE CONTRACT. THE INSERTION IS GRANTED AFTER SIGNING AND RECEIVING THIS DOCUMENT BY THE SERVICE PROVIDER. I HEREBY ORDER A SUBSCRIPTION WITH SERVICE PROVIDER INTERNATIONAL DIRECTORIES LTD “WORLD BUSINESS GUIDE”. I WILL HAVE AN INSERTION INTO ITS DATA BASE FOR THREE YEARS. THE PRICE PER YEAR IS EURO 995. THE SUBSCRIPTION WILL BE AUTOMATICALLY EXTENDED EVERY YEAR FOR ANOTHER YEAR, UNLESS SPECIFIC WRITTEN NOTICE IS RECEIVED BY THE SERVICE PROVIDER OR THE SUBSCRIBER TWO MONTHS BEFORE THE EXPIRATION OF THE SUBSCRIPTION. YOUR DATA WILL BE RECORDED. THE PLACE OF JURISDICTION IN ANY DISPUTE ARISING IS THE SERVICE PROVIDER’S ADDRESS. THE AGREEMENT BETWEEN THE SERVICE PROVIDER AND THE SUBSCRIBER IS GOVERNED BY THE CONDITIONS STATED IN “THE TERMS AND CONDITIONS FOR INSERTION” ON WEBPAGE: WWW.WORLD-BUSINESSGUIDE.COM
I haven’t checked out the full T&C, as I doubt I’ll benefit from such a listing.
This probably works best in large organizations, where one sucker responds to the spam and then the billing department responds automatically to incoming invoices. The two-month advance notice is a really nice touch, isn’t it?
Why do people continue to fall for this crap? If it didn’t pay off, the spammers would dry up and blow away, so there must be a fresh crop of suckers every day.
People, stop doing that!
Update: More on spam and what (not) to do: http://www.spamprimer.com/
Driving back from Cabin Fever, we passed the second-most-famous nuclear reactor site in the world.
After the fly ash spill last month in Tennessee, I’m waiting for calls to immediately shut down all coal-fired plants.
Maybe that’s like waiting for PETA to start picketing halal butcher shops. In Tehran.
Driving makes me way grumpy.
Back in the Good Old Days, 9 V batteries had a stack of half a dozen pancake cells inside that completely filled the outer case. These days, it seems they use cylindrical cells similar to AAAA cells, with more wasted space around the edges.
I retrieved these batteries from our smoke detectors. I tend to poke the self-test button occasionally and wait until the low-battery alarm starts chirping, rather than throwing half-used batteries out. Being that sort of bear, I date the batteries when I put them in; they usually last two years.
This one is from batteries.com and lasted 18 months. The obvious corrosion inside the shrink-wrap plastic sleeve says that the cell sealing isn’t nearly as good as you’d wish. The two most heavily corroded cells are completely dead, but the rest have about 500 mAh of life left in them (at a rather low 50 mA discharge rate). With a bit better QC, it’d be a winner.
Notice that the case contacts have sharp points that ensure a decent connection, perhaps despite the crud. Only one or two of the points actually make contact, which probably contributes to a faster assembly time: just get the ribbons in the right neighborhood and crimp the case closed. On the other hand, all the current must flow through one or two points, so don’t use them as a high-current source.
On the other end of the scale, this Eveready Gold battery has six loose cells and lasted 2.5 years. All the cells have roughly the same level of charge remaining: they’re thoroughly dead.
The build quality seems better, with individually shrink-wrapped cells and a compliant closed-cell foam layer on the bottom of the case to maintain pressure against the contacts. No sharp points, so they need more pressure.
The cell polarity is exactly reversed from what you’d expect: the button end is negative. So, even though this looks like a cheap source of AAAA cells, that’s a cruel deception…
Lots more info at http://data.energizer.com/
If you’re heavily into battery testing, you need something like a West Mountain Radio Computerized Battery Analyzer.
Ever notice how, when you take your car in for inspection, it always comes back with the wheel lug nuts tightened beyond the ability of mere mortals? I think it’s because they have their pneumatic impact wrenches turned up to 11, just to make sure the nuts never, ever come loose and expose them to liability.
Found this yesterday while walking back from the store with two gallons of milk. The shiny bit in the background is labeled SocketLug, which is evidently a trademark associated with Gorilla (but with no Web presence), and sports patent number 5797659. The stud in the front evidently snapped out of somebody’s wheel, probably flush with the surface. Gonna be trouble getting that out!
The lug is a threaded 9/16-inch steel stud, with a root area of maybe 0.18 square inches. Let’s suppose the yield strength is 100 kpsi, so breaking that thing required 18 k pounds. The thread looks to be 18 TPI for a 1.8 degree helix angle; call it 3%. If they lubed the threads and lug (ha!), letting us assume 20% friction, then the wrench was applying 700 pounds at a 9/32″ moment arm: call it 2.5 k lb-in or 30 k lb-ft of torque. Pretty impressive, given that typical pneumatic wrenches weigh in at around 500 lb-ft of torque.
Which says it really wasn’t the wrench doing the breaking, which should also be obvious because it was lying at the side of the road rather than on the shop floor. Even a 1000 lb-ft wrench would create only 5% of that yield load in the stud, so something else was wrong.
That orange patch in the upper left looks like rust in a crack, with the gray area in the lower right revealing the final fault. Maybe the shop monkey (or owner?) managed to whack it while installing the tire, create a small crack that let in the usual NYS road salt, and after a season or two the stud failed after being cranked tight once again.
There’s likely another four on that wheel: safety in numbers! Unlike those old Citroens with but a single nut securing each wheel…
The Smell of Molten Projects in the Morning 