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.

The New Hotness

  • Printed Fragment Coaster: Delamination and Pinhole

    Although “chipboard” is also known as “beer mat”, it’s not intended for long-term use under sweaty mugs. After a few weeks of daily use, this is obviously out of spec:

    Printed Fragment Coaster - moisture damage
    Printed Fragment Coaster – moisture damage

    The aforementioned sweaty mug lifted part of a fragment off the coaster:

    Printed Fragment Coaster - delamination
    Printed Fragment Coaster – delamination

    The chipboard is Quickboard from Makerstock, which is basically recycled-fiber chipboard with the advantage of being through-dyed in cheerful colors. It’s described as “2 mm-thick, three-layered board” and it looks like the core delaminated from the bottom layer.

    Seeing as how it’s near the end of Sweaty Mug season, I smeared Elmer’s Glue Stick PVA adhesive over the fragment, stuck it back in place, and declared victory.

    While doing that, however, I noticed a pinhole:

    Printed Fragment Coaster - delamination detail
    Printed Fragment Coaster – delamination detail

    You may recall the outline came from hand-tracing a fragment of smashed glass in GIMP to get a path, then 3D printing a base to hold it:

    Printed Coaster - Set C - oblique
    Printed Coaster – Set C – oblique

    Going back to the original GIMP tracing (storage being cheap, never delete anything), I missed a pixel:

    Printed Fragment Set C - GIMP selection - errant pixel
    Printed Fragment Set C – GIMP selection – errant pixel

    Surely you can see it, particularly because you know exactly where it is. Right?

    The (degenerate) path around that pixel becomes a tiny vector in LightBurn:

    Printed Fragment Coaster - Set C - orphan vector
    Printed Fragment Coaster – Set C – orphan vector

    It’s easier to see there. Right?

    Whereupon LightBurn dutifully punched a pinhole through the chipboard, because that’s what I asked it to do. It also punched that pinhole into the metallized paper reflector under the smashed glass fragment, but I didn’t notice it then, either.

    Shrinking the GIMP selection by one pixel width, then growing it by one pixel would eliminate single-pixel selections: just another item on the to-do list while tracing fragments.

    Ya learn something new every day around here …