Collector's guide
Collecting antique drafting instruments
Cased drawing sets, eidographs, pantographs and brass scale rules from the 18th to early 20th century form one of collecting's quieter corners: historically rich, usually affordable, and beautiful on a shelf. This is a beginner's orientation — what the categories are, which makers matter, and how to judge a set before you bid.
The main categories
- Cased drawing sets — the staple of the field. Fitted mahogany or rosewood cases holding brass compasses, dividers, ruling pens, and extensions, from pocket-sized sets to full shagreen-cased architect sets.
- Eidographs and pantographs — the scaling machines. Eidographs are stand-mounted and large (a dramatic display piece); pantographs range from cased brass bar-type to later wooden-beam forms. See how they differ.
- Scale rules and sectors — flat ivory, boxwood, or brass rules with graduated scales; the plainest entry point and easy to display.
- Drawing-office accessories — parallel rules, protractors, set squares, spring bows, and drafting machines from the early-machine era.
Makers worth knowing
| Maker | Where / when | Known for |
|---|---|---|
| W. & S. Jones | London, late 1700s–1800s | Early mathematical instruments; cased sets |
| Elliott Brothers | London, 1800s | Scientific and drawing instruments |
| W. F. Stanley & Co. | London, 1854 onwards | The classic British drawing-office range |
| Keuffel & Esser | New York, 1867 onwards | America's dominant drafting supplier |
| J. Halden & Co. | Manchester, late 1800s | Eidographs and drawing-office equipment |
| Coradi | Zurich, 1880s onwards | Precision pantographs, diagraphs, planimeters |
Judging condition
- Completeness beats polish. A complete set in a worn case generally outvalues a polished partial set; missing ruling pens or weights are the usual gaps.
- Check the joints. Compass joints should be firm; loose or repaired knuckles lower value. Steel parts should be honest gray patina, not active rust or over-polished plate.
- Fittings matter. Original velvet and silk linings, signed papers, and unbroken fitted slots add real value — relined cases are a visible repair.
- Signatures. Look for the maker's name engraved on the compass bar or fitted into the lid; signature and address together help date the set.
- Function, not just looks. Screws should turn, slides should move. Many old instruments still work perfectly — and using them is half the pleasure.
What drives value
Entry-level boxwood rules and small student sets start in the tens of dollars. Good Victorian cased sets from known London or New York makers typically range from one to a few hundred. Stand-mounted eidographs — rarer because of their size — run higher when complete with weights and plumb bob. The premium drivers, in rough order: maker rarity, completeness, case and lining condition, ivory or silver fittings, documented provenance, and geographic interest (local makers often carry a premium in their home region).
Where to find them
- Online auctions and marketplaces — the deepest supply; read listings carefully for completeness and inspect every photo of the case interior.
- Antique tool and scientific-instrument fairs — the best place to handle instruments and learn from dealers.
- Specialist dealers — higher prices, but graded, described, and often returnable.
- House-clearance and estate sales — occasional underpriced finds, especially of common student sets.
However your collection starts, keep the instruments working too — our scale calculator handles today's drafting while the brass stays on the shelf.