• Uranium 🟩@sh.itjust.works
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    1 year ago

    I imagine it’s order is:

    Ink

    Engrave

    Wipe off excess ink.

    So basically you use a little bit of ink roughly where the typeface will be, when the laser melts the plastic, some pigment will diffuse into the melted plastic, but the unmelted/undiffused stuff is still removable.

    If I had to guess this is how it’s actually done on the nicer older keycaps.

    Though I could be entirely wrong here…

    • wjrii@kbin.socialOP
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      1 year ago

      You’re right. The main challenge was just zeroing in on the point where the plastic softens to let the heated ink penetrate without deforming or burning the keycap. I think there’s potential here to do it better than I have, but I do think I landed on one of 2 or 3 different possible settings that will work decently well.

      It’s a low-rent form of dye-sublimation, and I don’t know if they’re using lasers, but dye-sub is one of the preferred ways to add legends to PBT keycaps.