# Hobby brass tube (K&S), 1/16–21/32 in and 1–12 mm, telescoping

> What sizes of K&S brass tube telescope into each other?

- Category: Hardware › Stirling & thermoacoustic
- Kind: Hardware
- Basis: K&S Precision Metals round brass tube: imperial sizes in 1/32 in OD steps with .014 in (0.36 mm) wall; metric 1–12 mm OD with 0.45 mm wall
- Page: https://xemstudio.com/objects/brass-tube-ks/ · JSON: https://xemstudio.com/api/geometry?object=brass-tube-ks · Plain text: https://xemstudio.com/objects/brass-tube-ks/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses

## Notes

- Imperial series telescopes: each size slides inside the next 1/32 in larger (OD 1/8 → ID of 5/32 is 0.128 in). Metric series telescopes in 1 mm steps (0.45 wall leaves 0.1 mm clearance).
- Also sold in aluminium (.014 wall, softer) and stainless (.010–.014). Cut with a tube cutter, deburr inside or the telescope jams.
- Why it's here: displacer rods and push-rods (3/32 and 1/8 in), displacer bodies (telescoping 1/2 → 17/32 for a close-fit sleeve), regenerator tubes, and thermocouple sheaths on the LES engines.

## Sizes

| size | od_mm | wall_mm | id_mm |
|---|---|---|---|
| 2/32 in | 1.59 | 0.36 | 0.88 |
| 3/32 in | 2.38 | 0.36 | 1.67 |
| 4/32 in | 3.17 | 0.36 | 2.46 |
| 5/32 in | 3.97 | 0.36 | 3.26 |
| 6/32 in | 4.76 | 0.36 | 4.05 |
| 7/32 in | 5.56 | 0.36 | 4.85 |
| 8/32 in | 6.35 | 0.36 | 5.64 |
| 9/32 in | 7.14 | 0.36 | 6.43 |
| 10/32 in | 7.94 | 0.36 | 7.23 |
| 11/32 in | 8.73 | 0.36 | 8.02 |
| 12/32 in | 9.52 | 0.36 | 8.81 |
| 13/32 in | 10.32 | 0.36 | 9.61 |
| 14/32 in | 11.11 | 0.36 | 10.4 |
| 15/32 in | 11.91 | 0.36 | 11.2 |
| 16/32 in | 12.7 | 0.36 | 11.99 |
| 17/32 in | 13.49 | 0.36 | 12.78 |
| 18/32 in | 14.29 | 0.36 | 13.58 |
| 19/32 in | 15.08 | 0.36 | 14.37 |
| 20/32 in | 15.88 | 0.36 | 15.16 |
| 21/32 in | 16.67 | 0.36 | 15.96 |
| 1 mm | 1 | 0.45 | 0.1 |
| 2 mm | 2 | 0.45 | 1.1 |
| 3 mm | 3 | 0.45 | 2.1 |
| 4 mm | 4 | 0.45 | 3.1 |
| 5 mm | 5 | 0.45 | 4.1 |
| 6 mm | 6 | 0.45 | 5.1 |
| 7 mm | 7 | 0.45 | 6.1 |
| 8 mm | 8 | 0.45 | 7.1 |
| 9 mm | 9 | 0.45 | 8.1 |
| 10 mm | 10 | 0.45 | 9.1 |
| 11 mm | 11 | 0.45 | 10.1 |
| 12 mm | 12 | 0.45 | 11.1 |

## Where the files are

- K&S Precision Metals: [Round brass tube (sizes and wall)](https://ksmetals.com/collections/brass-tube) — web — K&S site terms (verify at link)
- Wikipedia: [Brass](https://en.wikipedia.org/wiki/Brass) — web — CC BY-SA 4.0 (text)
- Long Earth Society: [Engine builds that use these parts (videos and write-ups)](https://longearthsociety.com/engineering/) — web, video — LES site

## Free STEP/STL (32 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/brass-tube-ks/index.json

- brass-2-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-2-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-2-32in.stl) — K&S round brass tube 2/32 in OD (1.59 mm), .014 in wall, 50 mm stub
- brass-3-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-3-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-3-32in.stl) — K&S round brass tube 3/32 in OD (2.38 mm), .014 in wall, 50 mm stub
- brass-4-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-4-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-4-32in.stl) — K&S round brass tube 4/32 in OD (3.17 mm), .014 in wall, 50 mm stub
- brass-5-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-5-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-5-32in.stl) — K&S round brass tube 5/32 in OD (3.97 mm), .014 in wall, 50 mm stub
- brass-6-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-6-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-6-32in.stl) — K&S round brass tube 6/32 in OD (4.76 mm), .014 in wall, 50 mm stub
- brass-7-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-7-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-7-32in.stl) — K&S round brass tube 7/32 in OD (5.56 mm), .014 in wall, 50 mm stub
- brass-8-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-8-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-8-32in.stl) — K&S round brass tube 8/32 in OD (6.35 mm), .014 in wall, 50 mm stub
- brass-9-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-9-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-9-32in.stl) — K&S round brass tube 9/32 in OD (7.14 mm), .014 in wall, 50 mm stub
- brass-10-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-10-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-10-32in.stl) — K&S round brass tube 10/32 in OD (7.94 mm), .014 in wall, 50 mm stub
- brass-11-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-11-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-11-32in.stl) — K&S round brass tube 11/32 in OD (8.73 mm), .014 in wall, 50 mm stub
- brass-12-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-12-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-12-32in.stl) — K&S round brass tube 12/32 in OD (9.52 mm), .014 in wall, 50 mm stub
- brass-13-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-13-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-13-32in.stl) — K&S round brass tube 13/32 in OD (10.32 mm), .014 in wall, 50 mm stub
- brass-14-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-14-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-14-32in.stl) — K&S round brass tube 14/32 in OD (11.11 mm), .014 in wall, 50 mm stub
- brass-15-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-15-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-15-32in.stl) — K&S round brass tube 15/32 in OD (11.91 mm), .014 in wall, 50 mm stub
- brass-16-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-16-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-16-32in.stl) — K&S round brass tube 16/32 in OD (12.70 mm), .014 in wall, 50 mm stub
- brass-17-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-17-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-17-32in.stl) — K&S round brass tube 17/32 in OD (13.49 mm), .014 in wall, 50 mm stub
- brass-18-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-18-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-18-32in.stl) — K&S round brass tube 18/32 in OD (14.29 mm), .014 in wall, 50 mm stub
- brass-19-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-19-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-19-32in.stl) — K&S round brass tube 19/32 in OD (15.08 mm), .014 in wall, 50 mm stub
- brass-20-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-20-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-20-32in.stl) — K&S round brass tube 20/32 in OD (15.88 mm), .014 in wall, 50 mm stub
- brass-21-32in: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-21-32in.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-21-32in.stl) — K&S round brass tube 21/32 in OD (16.67 mm), .014 in wall, 50 mm stub
- brass-1mm: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-1mm.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-1mm.stl) — K&S metric brass tube 1 mm OD, 0.45 mm wall, 50 mm stub
- brass-2mm: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-2mm.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-2mm.stl) — K&S metric brass tube 2 mm OD, 0.45 mm wall, 50 mm stub
- brass-3mm: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-3mm.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-3mm.stl) — K&S metric brass tube 3 mm OD, 0.45 mm wall, 50 mm stub
- brass-4mm: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-4mm.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-4mm.stl) — K&S metric brass tube 4 mm OD, 0.45 mm wall, 50 mm stub
- brass-5mm: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-5mm.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-5mm.stl) — K&S metric brass tube 5 mm OD, 0.45 mm wall, 50 mm stub
- brass-6mm: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-6mm.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-6mm.stl) — K&S metric brass tube 6 mm OD, 0.45 mm wall, 50 mm stub
- brass-7mm: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-7mm.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-7mm.stl) — K&S metric brass tube 7 mm OD, 0.45 mm wall, 50 mm stub
- brass-8mm: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-8mm.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-8mm.stl) — K&S metric brass tube 8 mm OD, 0.45 mm wall, 50 mm stub
- brass-9mm: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-9mm.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-9mm.stl) — K&S metric brass tube 9 mm OD, 0.45 mm wall, 50 mm stub
- brass-10mm: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-10mm.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-10mm.stl) — K&S metric brass tube 10 mm OD, 0.45 mm wall, 50 mm stub
- brass-11mm: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-11mm.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-11mm.stl) — K&S metric brass tube 11 mm OD, 0.45 mm wall, 50 mm stub
- brass-12mm: [STEP](https://xemstudio.com/files/hardware/brass-tube-ks/brass-12mm.step) · [STL](https://xemstudio.com/files/hardware/brass-tube-ks/brass-12mm.stl) — K&S metric brass tube 12 mm OD, 0.45 mm wall, 50 mm stub

## Questions

**Do K&S brass tubes telescope?**

Yes: the imperial series steps 1/32 in in OD with a .014 in wall, so each size slides into the next; the metric series steps 1 mm with a 0.45 mm wall.

**What is the ID of 1/8 inch K&S brass tube?**

0.097 in (2.46 mm): 3.175 OD minus two 0.356 walls. 3/32 in tube (2.38 OD) slides inside it.

**Which brass tube fits a 3 mm shaft?**

The 4 mm metric tube (3.1 mm ID) as a sleeve bearing; the 1/8 in imperial (2.46 ID) is too small.

## Fits with

- [Copper pipe (ASTM B88 Type L and M), 1/4 to 2 inch](https://xemstudio.com/objects/copper-pipe-type-l-m/)
- [Dowel pins, 2–6 mm (ISO 2338 / DIN 6325)](https://xemstudio.com/objects/dowel-pins-metric/)
- [Crank discs, connecting rods and flywheels for model engines](https://xemstudio.com/objects/crank-conrod-flywheel-kit/)
- [Borosilicate test tubes, 10×75 to 30×200 mm](https://xemstudio.com/objects/borosilicate-test-tubes/)