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.

Tag: Improvements

Making the world a better place, one piece at a time

  • Work Sharp Precision Sharpener: Clamp Support

    Work Sharp Precision Sharpener: Clamp Support

    Another Work Sharp Precision Adjust sharpener improvement from Printables:

    WorkSharp - clamp support
    WorkSharp – clamp support

    Although the blade clamp is a snug fit in its socket, it has enough stick-out cantilever to move slightly even under minimal force from the diamond tools.

    I added a thin cardboard shim, cut with a utility knife (!) and stuck on with a craft adhesive sheet, as the block was about half a millimeter upward with the clamp turned this-a-way and half a millimeter downward the other way. Your mileage / setup will certainly differ.

    I like the sharpener, but it’s much fiddlier than I expected.

  • Work Sharp Precision Sharpener: Turn Signals

    Work Sharp Precision Sharpener: Turn Signals

    The blade clamp on the Work Sharp Precision Sharpener fits into a socket that can rotate 180°:

    Work Sharp Precision Sharpener - Blade Clamp operation
    Work Sharp Precision Sharpener – Blade Clamp operation

    What’s not obvious is that the socket can rotate only 180°, which means you (well, I) must remember which way to turn it based on the presence or absence of the small white mark. I get it wrong somewhat more than half the time while sharpening a small symmetric blade, rather than a knife with a handle, so I added arrows to the socket.

    With the white mark upward, turn 180° counterclockwise:

    WorkSharp - turn CCW
    WorkSharp – turn CCW

    Then turn it 180° clockwise:

    WorkSharp - turn CW
    WorkSharp – turn CW

    As with the slug filling the uncomfortable button on the back side of the socket, this seems like it should be a standard feature.

  • Whirlpool Clothes Dryer: Heater Examination

    Whirlpool Clothes Dryer: Heater Examination

    A correspondent (you know who you are: thanks!) pointed out the Thermal Cutoff can trip should the 240 V heater coil sag enough to contact the grounded steel air duct surrounding it. Think of a connection from the heater in the lower right corner of the wiring diagram to the neutral wire:

    Whirlpool dryer - wiring diagram - detail
    Whirlpool dryer – wiring diagram – detail

    If the short is close to the middle of the heating element, the right half the heater will remain active even when all of the normal thermostats cut off the left half. The two half-elements will see about their usual 120 V and won’t burn out, but the right half will continue to heat the air until the Thermal Cutoff trips at 350 °F.

    A short near either end of the heating element will subject that section to a higher voltage than usual and promptly burn it out, in which case the dryer will fail to heat due to the much lower power dissipated in the remaining section.

    So I took the dryer apart after a (successful!) washing day to see if that had happened.

    A spring clip holds the top of the heater duct in place:

    Whirlpool Clothes Dryer - bulkhead parts - heater duct clip
    Whirlpool Clothes Dryer – bulkhead parts – heater duct clip

    AFAICT the clip cannot be disengaged from the duct in situ without removing the hex-head sheet metal screw holding it to the bulkhead, which requires inserting a 5/16 inch socket on the end of a 6 inch extension through a hole in the non-removable upper back cover. You (well, I) cannot see the screw from any position, so the process requires reaching up over the duct to position the socket by feel.

    This view looking up inside the dryer with the duct removed shows the clip on the bulkhead:

    Whirlpool Clothes Dryer - heater duct clip
    Whirlpool Clothes Dryer – heater duct clip

    The heating element looked to be in fine shape, with no sags or distortions:

    Whirlpool Clothes Dryer - heater top view
    Whirlpool Clothes Dryer – heater top view

    A side view:

    Whirlpool Clothes Dryer - heater side view
    Whirlpool Clothes Dryer – heater side view

    Taking a picture of the duct’s interior is impossible, but an eyeballometric inspection shows no burns / scorches / pits from contact with the coils:

    Whirlpool Clothes Dryer - heater duct interior
    Whirlpool Clothes Dryer – heater duct interior

    So AFAICT the Thermal Cutoff tripped due to Inherent Defect, rather than an overly high temperature.

    Reinstalling the duct requires fitting the spring clip into its slot in the duct, maneuvering the duct onto its lower bulkhead brackets without dropping the clip, persuading the top of the duct with the clip into position, getting the screw into the clip and the hole, then aligning the socket with the screw. If I were doing this for a living, I would definitely charge you extra; newer dryers have an easily removable heating element for well and good reason.

    So the dryer is, once again, back together again and, once again, works as well as it ever did, with another set of thermostats / cutoffs in the box of dryer and washer parts against future need.

    For reference, the heater seems to be a WP4391960.

  • Battery Organizer

    Battery Organizer

    A small box has been holding an assortment of batteries during their out-of-service phase and I finally made a lid to keep the contents from flopping around:

    Battery organizer
    Battery organizer

    The cardboard prototypes record the journey toward the black acrylic lid. The final LightBurn layout:

    Battery Collector - LightBurn layout
    Battery Collector – LightBurn layout

    For whatever it’s worth, the box holds:

    The first four suitable & identical screws from the Tray o’ Tiny Screws hold the lid down. The ToTS contains screws and suchlike harvested from all the gadgetry headed for the recycling pile, making it a reliable source for any occasion.

  • Pressure-washed Stove Grates

    Pressure-washed Stove Grates

    Be it hereby declared: laying the absurdly heavy cast-iron grates from the stove on sawhorses in the driveway and pressure-washing them produces a dramatic improvement:

    Pressure-washed stove grates
    Pressure-washed stove grates

    They’re now devoid of the oil / grease / carbon accumulated during their decade of existence, little of which can be removed by hand; the shiny spots on the front right shrug off all solvents in my armory. The black finish still has plenty of scrapes & scuffs, but it’s no longer annoying.

    You might think Samsung stove grates would fit in a Samsung dishwasher, but they’re too big and too heavy.

    Also for the record: cyanoacrylate adhesive works wonderfully well to hold their little rubber feet in place.

  • PolyDryer Humidity: April-ish

    PolyDryer Humidity: April-ish

    After about five weeks:

    2026-04-16
    Filament%RHWeight – gWt gain – gGain %
    PETG White14
    PETG Black14
    PETG Orange2252.52.55.0%
    PETG Natural15
    PETG-CF Blue2355.45.410.8%
    PETG-CF Gray18
    PETG-CF Black14
    PETG Blue10
    TPU Clear14
    TPU Black14

    Most of the PolyDryer boxes had the same humidity as before, so I didn’t disturb them. When the humidity starts to rise, then we’ll see what’s going on in there.

    The PETG Orange meter continues to misbehave and has been glitching from 22% to 30%. The indicator card shows the humidity is around 10% inside and the relatively low weight gain suggests there’s not much water to be adsorbed.

    The PETG-CF Blue spool is new and, once again, shows filament does not arrive bone-dry in the factory wrapper.

    Those two boxes now have alumina beads.

    Dehydrating the jar of wet silica gel on the induction cooktop (set for 405 °F) sweated it down from 532 g to 503 g over the course of four hours, with nearly all of that change in the first two hours.

    Obligatory photo from a while ago, because it looks pretty much the same now:

    Silica gel beads - drying
    Silica gel beads – drying
  • Punched Cards: Summary

    Punched Cards: Summary

    At last, I can make plausible-looking punched cards:

    Test Card 3 - punched
    Test Card 3 – punched

    Then chop most of them up to make a layered eagle:

    Apollo Eagle - V3 - overview
    Apollo Eagle – V3 – overview

    Back in the beginning, the grand overview explained the card production process, but now I can pull all the blog posts into a more coherent story.

    Start by making trays to hold the 1/3 Letter sized printed cards and the final cut cards. A coat of paint improves the result:

    Card Storage Tray - front
    Card Storage Tray – front

    Then make a fixture to position the 1/3 Letter printed cards in the laser and a simple cover for the honeycomb to direct the air flow:

    Punched cards - laser fixture overview
    Punched cards – laser fixture overview

    The current versions of the Python program to convert a line of text into the SVG images required to print and punch the cards, plus the Bash scripts handling all the command line parameters, are now in a single GitHub Gist . I used the source code from the Apollo 11 CSM AGC for historic reasons.

    The Bash scripts invoke the Python program twice to produce both the printed layout:

    Punched Cards - test card - printed
    Punched Cards – test card – printed

    And “punched” holes surrounded by the perimeter cut for the laser:

    Test Card 3 - LightBurn layout
    Test Card 3 – LightBurn layout

    The Python program handles translation from the ASCII (really Unicode) character set into the EBCDIC punched hole layout. Because LightBurn and Inkscape handle SVG scaling differently, the script sorts that out.

    Because my printer produces slightly off-size printed images, the script uses Inkscape to convert the SVG into a PNG, then downscales the image by a few percent (a different percent on each axis). It composites the card logo onto the PNG and slams the result onto a Letter page in the proper place to hit the 1/3 Letter sheets.

    Aligning the targets printed on the cards with the corresponding target positions in the laser SVG requires careful fixture skootching:

    Red dot vs printed target vs laser spot alignment
    Red dot vs printed target vs laser spot alignment

    A batch file feeds the laser SVGs into LightBurn, so the process boils down to a few mouse clicks per card.

    With a tray full of finished cards in hand, I converted the eagle from the Apollo 11 mission patch into a set of outlines:

    Apollo 11 Patch - eagle layers
    Apollo 11 Patch – eagle layers

    Each of those outlines defines the shape of a layer cut from those printed cards:

    Apollo Eagle - V3 - head
    Apollo Eagle – V3 – head

    Not gonna lie: it took serious effort to cut up those cards.

    Each layer has a specific set of cards chosen to put the holes in the proper place while hiding the card joints:

    Apollo Eagle - V4 Layer 1 cards
    Apollo Eagle – V4 Layer 1 cards

    Mirroring the layout helped me arrange the cards correctly while taping the back side of the joints with book repair tape:

    Apollo Eagle - V4 Layer 1 cards - mirrored
    Apollo Eagle – V4 Layer 1 cards – mirrored

    Slap a sheet of cards on the laser platform, align it to the layer’s outline, Fire The Laser, and stack up the results:

    Apollo Eagle - V3 - tail
    Apollo Eagle – V3 – tail

    I used Elmer’s All Purpose Glue Stick to hold the layers together, figuring if it’s good enough for kindergartners it’s good enough for me.

    And that’s all there is to it …