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.

Category: Oddities

Who’d’a thunk it?

  • Cassini Saturn Orbiter vs. Tin Whiskers

    Although I don’t often block-quote other sources, for this I’ll make an exception:

    The Cassini Plasma Spectrometer (CAPS, off since June 2011) was powered back on on March 16 based on the unanimous agreement of the review board at the CAPS turn-on review held on March 8. All went as planned for both the instrument and the spacecraft during the turn-on. The high rail to chassis short internal to the instrument that was part of what prompted it to be turned off last June was not present, and no changes were seen in the bus voltages or currents when the turn-on occurred. On Tuesday, March 20, the high rail to chassis short in the CAPS instrument returned, generating the same condition that existed at the time the instrument was turned off. However, based on the tin whisker model developed by the NESC team, this condition is believed to be understood and is not expected to cause any problems for either the instrument or the spacecraft. The CAPS instrument has been left powered on and is sequenced to operate as originally planned for the 75 kilometer Enceladus flyby coming up on March 27.

    Having seen a forest of tin whiskers myself, that’s a pretty scary diagnosis. One assumes NASA takes extensive precautions, based on their experience, but … 15 years in hard vacuum and free fall will do odd things to spacecraft.

    Remember those Toyota unintended acceleration problems? Guess what caused some of them: yup. Read their report to find out what makes metal whiskers so hard to detect. Hint: combine a minimum threshold voltage with a very low current capacity.

    You could subscribe to the Cassini Significant Events newsletter.

  • CH-47 Flyover

    I have no idea what’s going on around here any more…

    CH-47 helicopter formation
    CH-47 helicopter formation

    Those northbound CH-47 Chinooks looked to be barely over treetop level, but the rotors are 60 feet in diameter and they were much higher than they seemed. Shook the house and brought all hands outside to watch the show.

    I remember getting a tour inside one, a long time ago, at a military air show.

  • Bald Cardinal

    Something weird is going on with the Northern Cardinals at our feeder. First a female missing a leg, now a male minus his head feathers:

    Bald Cardinal - right side
    Bald Cardinal – right side

    A view from the other side:

    Bald Cardinal - left side
    Bald Cardinal – left side

    A bit of searching with the obvious keywords produced that writeup, which suggests feather mites or other parasites. Given that this was in March, that cardinal is definitely not molting!

    Those pictures are tight crops from a hand-held Canon SX230HS at dusk, through two layers of 1950-vintage glass. Sorry about that, but the bird spooks whenever I crack the door open for a better view.

  • Helicopter Flyover

    Helicopter formation
    Helicopter formation

    While I was puttering around outside (an admittedly rare occurrence), a deep thuttering over the northern horizon eventually resolved into a formation of four helicopters. Hard to tell at this range, but they looked like Black Hawks southbound for the Stewart Air National Guard field.

    Our Larval Engineer reports that the college ROTC contingent includes some pilots-in-training who regularly land Black Hawks on the campus outfields.

    We are, fortunately, not in a part of the world where Bruce Cockburn’s commentary applies…

  • Not a Hand Hole

    Abraham Lincoln once observed that calling a tail a leg doesn’t make it a leg, which seems to apply perfectly to this situation:

    Not a Hand Hole
    Not a Hand Hole

    Surely, the real reason boils down to:

    • A warehouse full of boxes with pre-cut hand holes
    • A stack of returns due to guys poking their hands too far into the boxes
    • A desire to disallow said returns

    I bet they pick up the box that way, too.

  • Yellow Iron: Puzzling Placards

    The local construction equipment supplier deploys otherwise-idle yellow iron in all the parking lots in preparation for snow season. They haven’t gotten much use this year, which is OK by me.

    A Komatsu excavator behind a bank sports some puzzling warning placards:

    Komatsu excavator waiting for snow
    Komatsu excavator waiting for snow

    This one seems to mean you should stay out from underneath the bucket, which makes sense:

    Komatsu warning placard 2
    Komatsu warning placard 2

    But what’s this one mean? You may be crushed, so keep your distance from doors?

    Komatsu warning placard 1
    Komatsu warning placard 1

    Maybe read the manual before / while being backed over?

    Komatsu warning placard 3
    Komatsu warning placard 3

    Even though this stuff has become entirely too abstract for me, it’s just another day in the life for Stickman!

  • Red Oaks Mill Dam: Fading Fast

    A combination of neglect and last year’s storms demolished much of the Red Oaks Mill dam:

    Red Oaks Mill dam - after collapse
    Red Oaks Mill dam – after collapse

    The linear “rocks” just downstream of the dam are sections of the concrete cap:

    Red Oaks Mill dam - displaced concrete
    Red Oaks Mill dam – displaced concrete

    With the cap gone, the concrete-and-rock fill should disintegrate in short order:

    Red Oaks Mill dam - crumbled section
    Red Oaks Mill dam – crumbled section

    Upstream of the rubble, the Wappingers Creek dropped about three feet, exposing bedrock and undercutting the old shoreline:

    Red Oaks Mill dam - exposed creek bed
    Red Oaks Mill dam – exposed creek bed

    Downstream, not much changed. This wasn’t a catastrophic dam break that wiped entire towns off the map.

    In February 2005, the fishing must have been pretty good:

    Red Oaks Mill Dam - 27 Feb 2005
    Red Oaks Mill Dam – 27 Feb 2005

    It’s endured quite a few floods like this one in February 2008:

    Flood Stage in Red Oaks Mill
    Flood Stage in Red Oaks Mill

    But in June 2008, after the waters receded, you could tell things weren’t right:

    Red Oaks Mill Dam - 2008
    Red Oaks Mill Dam – 2008

    Looks like a shovel-ready project to me…