A book about design and making · work in progress

The Hundred-Year Chair

Making Things Worth Keeping

I started with a pile of wood scraps and an urge to make a chair. This book follows the experiments, mistakes, and people that changed how I thought about design and the things we live with. Read the manuscript, explore the drawings, or build a chair of your own.

Kratstoel, Gerrit Rietveld, 1934, white-painted period example — Krat-stoelGerrit Rietveld, 1934. Priced to the guilder; drawn to be built by its buyer. Photo: Centraal Museum Utrecht.

The ten-dollar replica in black film-faced plywood with the wide 100 mm arms, 2026 — The ten-dollar replicaThe same drawing, rebuilt from salvage in 2026, carrying the wide arm of the museum’s own 1934 chair rather than the sheet’s narrow one. In ply the split that punished that arm in pine cannot propagate.

Vilbert chair, Verner Panton for IKEA, c. 1993 — VilbertVerner Panton for IKEA, c. 1993. Four panels, briefly produced; the fruitful error that started the search. Photo: dealer listing, Pamono.

The Keel Chair in side elevation against a grey backdrop: black film-faced plywood back, seat and tie panels seen edge-on with their pale ply edges showing, a cherry keel running as one long diagonal from the top of the back down to the floor, and a pale plywood front leg crossing it — Keel ChairThe search led to the Keel Chair, embodying the pattern of two congruent triangles sharing a keel. Black film-faced plywood on a cherry spine, photographed 7 September 2026.

Build · the atoms

Chair Plans, Patterns, and Builds

Four chairs with photographs, part drawings, instructions and plans in millimeters or inches: Rietveld’s 1934 Kratstoel, the Keel Panel dining chair, the Keel Truss lounge chair, and the 1000 Year Chair. Free to build, change and sell under CC BY 4.0.

The Hundred-Year Chair: Making Things Worth Keeping, by Karl T. Ulrich

Verify · the weeds

Technical Notes

The details the narrative keeps out: why bolted joints go slack, how wide the keel has to be, doing mechanical CAD by conversation. Every claim says whether it is verified, standard, derived, or unverified.

Instruments: the Fan (a century of seat-and-back geometry) · the Timeline (watch the design walk from the Vilbert to the truss) · the Gallery (the workshop record in photographs) · the Lineage (the family tree, dated against the tape) · the Tape (the collaboration itself, measured: bouts, tokens, bits and atoms) · the Ledger (every open verification item, in one place)

The Hundred-Year Chair · hundredyearchair.com · prototype, August 2026. Every figure on this site is generated from the same scripts that cut the chair; where a value is estimated rather than measured, it says so. The four photographs above are the pedigree in the flesh; the scale drawings live on in the timeline. Archival material: Centraal Museum Utrecht, Rietveld Schröder Archive.