Jens Kutilek reverse-engineers the IBM Selectric Composer’s 9-unit spacing system to produce accurate OpenType revivals of its typefaces, including Selectric UN 11 Medium.
Key Takeaways
The Selectric Composer used 7 spacing groups (3-9 units/em) and three color-coded unit scales (red/yellow/blue), requiring per-size UPM correction factors when digitizing.
Drawing at 900 UPM maps 1 composer unit to 100 font units; exporting at corrected UPMs (933, 1000, 1050, 1100) aligns physical output size to original spec.
Fixed unit assignments forced Frutiger to distort Univers letterforms: g is too narrow, s is too narrow, T and F too wide – artifacts that fingerprint Composer-set text.
German locale required dropping characters to fit umlauts/eszett, forcing further width compromises (e.g., u wider than u).
Optical size variants need separate drawings; autotrace is rejected in favor of manual redrawing over catalog scans inside Glyphs app.
