Recreating IBM Punched Cards

Being in need of punched cards for a project, the first step required making Old-School IBM-style punched cards from scratch:

A Python program generates a pair of SVG files defining the printed layout and the cutting pattern for each card. Some hocus-pocus with Inkscape and ImageMagick adjusts the “print” SVG to match the “cut” SVG.

The cards are pre-printed on 1/3 Letter sheets with text along the top, hole / column numbers, and registration targets:

The source code comes from the Apollo Guidance Computer used in the Apollo 11 Command Module. The card sequence numbers, logo, and colors are non-canon. :grin:

With all the cards printed, a Windows batch file feeds the “cut” SVGs to LightBurn in sequence, reducing the production process to a few clicks and simple alignment for each card.

A fixture holds each card on the platform:

LightBurn imports the “cut” SVG at the center of the workspace, so I skooch the fixture to align the printed targets with their corresponding design targets:

The printed layout can vary a few millimeters and degrees from dead center on each 1/3 Letter sheet, but the overall pattern is consistent enough. Defining the upper-right and lower-left target coordinates as Saved Positions makes moving the laser head a matter of single key taps while I’m skooching the card.

Engraving the holes, rather than cutting them, produces straight sides and square corners without the usual wobbles:

The final cut drops the card onto the honeycomb:

Laser-cut trays keep the card stacks tidy:

The process is definitely not a replacement for a skilled IBM 029 keypunch operator with a box of cards, but it worked out better than I expected :grin:

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…I would call that rocket science :wink:

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