Xem Studiomeasured geometryLibrary › Hardware › Found & household materials ·
Glass marbles 1/2 in, 5/8 in and Ø16 mm
What is the diameter of a standard marble? · Standard part · basis: Marbles are sized by diameter in 1/16 in steps, usually 1/2 to 3/4 in (marblecollecting.com); files are spheres at 1/2 in (Ø12.70), 5/8 in (Ø15.875) and Ø16.0
Long Earth Society build part. Frames, crank wire and guides for the no-budget can engine. The engines
Exact dimensions. True size, with no printing tolerance added.
- sizes
- 3 in table
Notes
- Glass marbles are sized by diameter in 1/16 in steps and are usually 1/2 to 3/4 in. The files are spheres at 1/2 in (Ø12.70), 5/8 in (Ø15.875) and the metric Ø16.0.
- Tournament rules put shooters between 5/8 and 3/4 in.
- In the test-tube marble engine, four 5/8 in marbles roll inside a 25 × 150 tube (Ø22.6 bore) as the displacer; one marble fits across the bore, so they roll in single file.
- Marbles vary from piece to piece by a few tenths of a millimetre; measure the one you have before you draw anything around it.
Sizes
| marble | dia_in | dia_mm |
|---|---|---|
| 1/2 in | 1/2 | 12.7 |
| 5/8 in | 5/8 | 15.875 |
| 16 mm | None | 16.0 |
Where the files are
Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.
| Wikipedia | Craft stick | web | CC BY-SA 4.0 (text) |
| Wikipedia | BB gun | web | CC BY-SA 4.0 (text) |
| Wikipedia | Table tennis | web | CC BY-SA 4.0 (text) |
| Long Earth Society | Engine builds (videos and write-ups) | web, video | LES site |
Free files
★ Free files 3 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json
| marble-16mm | glass marble Ø16 (15.9); shooter Ø25 | STEP · STL |
| marble-5-8in | glass marble 5/8 in (Ø15.875), the common size | STEP · STL |
| marble-1-2in | glass marble 1/2 in (Ø12.70) | STEP · STL |
Plain text: sheet.txt · JSON: /api/geometry?object=glass-marbles
How it fits
Goes in or on
Borosilicate test tubes, 10×75 to 30×200 mmthe marble displacer of the test-tube engineAlternatives
BBssmaller balls, Ø4.5 and Ø6
Ping-pong ball Ø40 mm, 0.4 mm walla larger, hollow, much lighter ball (Ø40)In these build lists
Test-tube marble enginecrank and flywheel at the end.You might also need
Questions
What is the diameter of a marble?
Marbles come in 1/16 in steps, usually 1/2 to 3/4 in; the common size is 5/8 in (15.875 mm, often sold as 16 mm).
Are marbles all the same size?
No; they are sized by the smallest sieve opening they pass, and individual marbles vary by a few tenths of a millimetre.
What marbles go in a test-tube marble engine?
5/8 in (Ø15.875) in a 25 × 150 tube (Ø22.6 bore): they roll in single file from end to end as the tube rocks.