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

  • Astable Multivibrator Blinkies: Radome Attachment

    Ping-Pong ball radomes tend to fall off their perches at the slightest touch:

    RGB LED - radome test
    RGB LED – radome test

    Because I planned to take my collection along to HV Open’s Mad Science Fair, I finally used a Round Tuit for some adhesive action.

    The general plan was to punch a ring from double-sided tape, thusly:

    Astable - Radome adhesive - poor surface
    Astable – Radome adhesive – poor surface

    The OD required touching up the edge of a brass tube punch I’d made a while ago:

    Astable - Radome adhesive - punch sharpening
    Astable – Radome adhesive – punch sharpening

    It worked exactly as expected:

    Astable - Radome adhesive - punching
    Astable – Radome adhesive – punching

    Unfortunately, the 3D printed spider’s “spherical” socket has such a rough surface that the adhesive had too few contact points to hold the ball in place.

    My fallback has become 3M outdoor-rated double-stick foam tape, so:

    Astable - Radome adhesive - 3M foam tape
    Astable – Radome adhesive – 3M foam tape

    This leaves a small black ring visible between ball and socket. Recessing the foam tape by half its thickness should improve its ahem optics, although it’s probably not worth the effort with black PETG.