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

  • Punched Cards: Layered Apollo Eagle

    What with punching the Apollo 11 CSM source code into the cards, converting the mission’s eagle into a layered shape made some sense.

    The original Apollo 11 mission patch:

    Apollo 11 mission patch - rescaled
    Apollo 11 mission patch – rescaled

    After considerable faffing, a few of the fifteen layers look like this in GIMP:

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

    Each layer is a connected white region defining the cut perimeter, which will expose some part of the layer(s) below it in the stack. The small squares in the corners provide a bounding box to make all the layers snap to the same location.

    Then:

    • Select each layer’s shape + corner boxes with GIMP’s Color Select tool
    • Convert the selection to a path
    • Export paths as SVG files (all fifteen of them!)
    • Import SVGs into LightBurn & arrange neatly
    • Put outlines on a cut layer, corner squares on a tool layer
    • Burn each layer separately

    Testing the concept with packing paper looked surprisingly good:

    Apollo 11 Eagle - layer test piece
    Apollo 11 Eagle – layer test piece

    A few key layers on punched cards:

    Apollo 11 Eagle - card partial test piece
    Apollo 11 Eagle – card partial test piece

    The changes for each of those iterations required tweaking the original layer images to eliminate obvious-in-retrospect problems, recreating the SVG files, and importing into LightBurn. This is a relentlessly manual process.

    Then I ran a full-up test of all fifteen layers on cards punched with the Apollo source code.

    Cutting the head layers from face-down cards made them sufficiently white, although it’d be nice to have a different beak color and darker eyes :

    Apollo 11 Eagle patch - layer test - head
    Apollo 11 Eagle patch – layer test – head

    I must arrange the cards with text to put more holes in the wings, although too many will cause fragile feathers:

    Apollo 11 Eagle patch - layer test - wing
    Apollo 11 Eagle patch – layer test – wing

    The white tail should be also done with face-down cards, more holes, and the three-way joint between the cards shifted under the tail layers to its left:

    Apollo 11 Eagle patch - layer test - tail
    Apollo 11 Eagle patch – layer test – tail

    The feet and olive branch were a total faceplant, as successive layers did not register accurately enough to overlay the leaves:

    Apollo 11 Eagle patch - layer test - feet
    Apollo 11 Eagle patch – layer test – feet

    Not to mention those ug-u-lee claws.

    The wing layers need more rounding along their edges, perhaps with some thin cuts to emphasize the feathers.

    On the whole, though, I think it turned out well.

    Things to do:

    • Registration holes / pins up to the top layer
    • Remove speckles on all the layers
    • Arrange cards for more hole density where needed
    • Better glue application
    • Different card colors?