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.
My buddy Eks just replaced his host-water furnce with a high-efficiency unit.
Can you tell that Eks is an engineer?
The plumber used one of those fancy pipe-compression tools that mashes the mating parts together with an O-ring for sealing. Faster and safer than sweating the joints together, but I want to fast-forward two or three decades to check out the durability.
As he put it, “You may be able to get a better furnace installation, but you probably can’t pay any more for it…”
Having decided to try getting sunglasses from one of those “our lab is in Hong Kong” places, the question arises: what lens & frame size do I need?
Rummaging through the heap produces this assortment:
| Frame label | Lens size | Frame width | Earpiece | Commentary |
| 53-19 | 53×40 | 141 | 145 | Current glasses |
| 55-16 | 55×45 | 142 | 140 | Current sunglasses |
| 54-16 | 54×45 | 133 | 135 | Old sunglasses |
| 56-16 | 56×45 | 137 | 133 | Wire rims, aviators |
| 52-19 | 52×39 | 140 | 140 | Clear, previous daily |
| 56-16 | 58×50 | 135 | 130 | Aviators, too big |
The obvious conclusion is that any lens in the low 50s x 40-ish range will suffice. Pity that the LPS (low-price supplier) doesn’t have anything non-aviator-ish or un-dorky (even by my slack standards) in the 40-ish range, but maybe it’ll work out OK.
Some general observations.
I used to wear relatively large aviator-style lenses, as I worked on little parts that occasionally went sproing. Not enough energy to merit safety glasses, but annoying enough to want good eye coverage. These days, alas, I tend to wear a headband magnifier.
Progressive bifocals require a relatively tall (and, it seems, currently unstylish) lens. Aviators solve that problem, but really are too large for my face. No matter that I wore them for years.
Anti-reflection coating is wonderful. Pity that the LPS can’t put it on tinted lenses; I’ll see how that works out.
I wear one pair of glasses all day, every day, and take fanatic care of them; we have an ultrasonic cleaner pretty much dedicated to eyewear. By and large, my lenses last forever. The frames, as you’ve seen there, tend to fail first.
[Update: It turns out 53×35 lenses really aren’t tall enough for gray 20% transmission sunglasses: the progressive transition is a bit cramped and there’s too much daylight around the top & bottom. I think they’ll be OK for biking, as I wear hideous goggles to keep the dust out of my eyes. A pupillary distance of 62 seems OK. About $63 delivered.]
The turkeys were discussing their activities yesterday evening while getting ready for bed in the trees out back. This isn’t unusual, but they seemed rather louder than usual.
We walked out the driveway, me with the Sony DSC-F717 in IR Night Shot mode, and eavesdropped for a while. The two early birds in the trees may have been air bosses for the rest of the flock, as nobody else arrived while we were there.
So I didn’t get any pictures, but it reminded me of some I took a few years ago when a hen with a gaggle of chicks roosted in a maple directly in front of the house.
Three peeps are easy to see, but she had at least two others snuggled up on her left side!
As described there, I set up a cron job to back up our low-budget file server to an external USB drive and turn it off for the night.
After a while, it became painfully obvious that
shutdown -P now
was, at best, intermittently successful at turning off the power. The shutdown sequence would sometimes hang near the end, with a blank screen, after unmounting all the drives (so there are no logs), with the power on. Keyboard & mouse were dead, tapping the power button produced a display about acpid being unhappy, but nothing I could follow up.
Oddly, that same command issued from a terminal window would work perfectly for as long as I was willing to restart the machine.
Even more oddly, the box would shut off properly from the GUI or the GDM login scren.
A puzzlement…
After several days of tedious “try this” experimentation and rummaging through the scripts in /etc/init.d/, it seems this command works in the cron job the way it’s supposed to
halt -p -f
The -p calls for a power-down and -f says to force the halt (rather than calling shutdown, which we know won’t work).
So, finally, I can hack 25% off the power bill for that thing.
Memo to self: some day, figure out exactly how the whole shutdown sequence works.
The Smell of Molten Projects in the Morning 