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?

  • Vacuum Tube Lights: Urethane Coated Plate Cap

    Vacuum Tube Lights: Urethane Coated Plate Cap

    With a generous dollop of JB Plastic Bonder left over from a set of Bafang brake sensor magnets, I tried coating the ersatz plate cap of a triode tube:

    Triode - urethane coated plate cap
    Triode – urethane coated plate cap

    That’s the result after leaving it hanging upside-down while it cured to push all the drips to the top.

    For comparison, the uncoated cap back in the day:

    Triode - plate cap plug
    Triode – plate cap plug

    Seeing as how the urethane is an adhesive, not a coating, I’d say it looks about as bad as expected.

    As with all 3D printed things, one must embrace imperfections and striations, rather than endlessly strive for perfection.

    Now, if I had a resin printer …

  • Tour Easy: Amber DRL Internal Resistor

    Tour Easy: Amber DRL Internal Resistor

    Plotting current against voltage for the amber truck side marker lights produces the expected straight-ish line:

    Side Marker I vs V plot - with fuse
    Side Marker I vs V plot – with fuse

    The slope suggests a 330 Ω resistor, but the internal PCB sports a pair of 150 Ω SMD resistors.

    I don’t believe the X-axis intercept for a moment, but 1.5 V seems about right for an amber LED.

    Oh, and the DMM fuse doesn’t have a ceramic body. You’re seeing the vaporized remains of a 315 mA fuse neatly deposited over the inside of the glass tube after being shorted across a 3 A bench supply.

    I hate it when that happens. Replacing it emptied the little bag of those meter fuses; next time it’ll get a half amp fuse.

  • Carolina Wren Construction

    Carolina Wren Construction

    A great musical interlude on the patio announced an airlift of construction materials eventually producing this pile inside the top cover of the propane tank:

    Carolina Wren - nest started atop propane tank
    Carolina Wren – nest started atop propane tank

    The male Carolina Wren switched from the Tweedle of Great Nestbuilding to the less musical Mighty Chirr of Disapproval, presumably because he noticed a mouse (or, perhaps, chipmunk) occupying the lower ring of the tank. Rodents and birds do not coexist well at all; I have no doubt a mouse would climb right up the tank for a supply of breakfast eggs.

    I must blow the crud off the tank before the next fill.

  • Homebrew Mint Extract

    Homebrew Mint Extract

    I clearcut a stand of spearmint and turned it into three jars of what should become mint extract:

    Homebrew mint extract - start 2021-06-17
    Homebrew mint extract – start 2021-06-17

    The left jar has 3 ounces of mint mostly covered with 80 proof vodka and the other two jars each have 5 ounces submerged in 180 proof grain alcohol.

    Nine days later:

    Homebrew mint extract - 2021-06-26
    Homebrew mint extract – 2021-06-26

    The vodka is now on the right and shows a weird layering caused by the leaves extending above the light yellow liquid; I’ve been inverting the jars every few days. The grain alcohol looks more like the previous iteration, with uniformly decolored leaves in dark green liquid.

    A closer look:

    Homebrew mint extract - vodka vs grain alcohol - 2021-06-26
    Homebrew mint extract – vodka vs grain alcohol – 2021-06-26

    What’s happening in the vodka jar does not look like a nominal outcome …

  • Discrete LM3909: Green and Blue vs. Dead Alkalines

    Discrete LM3909: Green and Blue vs. Dead Alkalines

    These two discrete LM3909 circuits recently stopped blinking:

    LM3909 AA alkaline - Green and Blue
    LM3909 AA alkaline – Green and Blue

    The green LED (on the left) took six months to wear its pair of not-dead-yet AA alkalines from 2.7 V down to nearly zero.

    The blue LED in the radome took two months to go from 1.0 V (!) to nearly zero. It didn’t start very bright and went decidedly dim along the way, but the LM3909 circuitry still managed to jam a few microamps through the LED.

    In both cases, one of the cells was reverse-charged by a few hundred millivolts, although neither leaked.

    Both got another set of not-quite-dead AA cells and they’re back in action.

  • Bird Nest Material: Plastic String

    Bird Nest Material: Plastic String

    This nest appeared in a path near Mary’s Vassar Community Gardens plot:

    Bird Nest with plastic string - top
    Bird Nest with plastic string – top

    The bird obviously took advantage of modern technology, because it’s held together with generous loops of plastic string:

    Bird Nest with plastic string - bottom
    Bird Nest with plastic string – bottom

    We don’t know where it came from or how it got onto the path.

  • Snapping Turtle on the Move

    Snapping Turtle on the Move

    A snapping turtle headed toward the beaver pond on the Dutchess County Rail Trail:

    Snapping Turtle - DCRT - 2021-05-26
    Snapping Turtle – DCRT – 2021-05-26

    At this time of year and phase of the moon, she is most likely in search of a good spot for a nest and her clutch of eggs. Being an aquatic creature, she and her progeny surely benefit from Team Beaver’s engineering.

    Today I Learned: snappers are the New York State Official Reptile.