# 2 in × 3 in spool with the bore finished Ø48.00 (bored and honed power cylinder)

> How do I turn a 2 in tri-clamp spool into a piston cylinder?

- Category: Hardware › Stirling & thermoacoustic
- Kind: Hardware
- Basis: Stock 2 in × 3 in spool (ISO 2852 faces, ASME BPE tube); the finished bore is a design value
- Page: https://xemstudio.com/objects/tri-clamp-spool-bored-honed/ · JSON: https://xemstudio.com/api/geometry?object=tri-clamp-spool-bored-honed · Plain text: https://xemstudio.com/objects/tri-clamp-spool-bored-honed/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

**Exact dimensions.** Every file is drawn at true size with no printing tolerance. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your printer's or process's clearance before making the part.

## Notes

- A standard 2 in × 3 in spool sent out to be bored and honed through to Ø48.00. Stock tube is made to its OD and wall, so its bore can be anywhere from about 46.8 to 48.0 mm and is not round to a sliding standard; Ø48.00 cleans up every tube in tolerance and leaves about 1.4 mm of wall.
- The bore is a running fit for the Ø48.00 × 34 clearance-seal piston (no rings): the honed bore and the piston's ground OD together are the seal. Both performance engines use it with a 36 mm stroke.
- Honed surface: the whole bore face to face. The faces stay as made.

## Mating features (exact size; open press / slide / run / socket by your process clearance, leave designed and clamp as drawn)

| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| faces | ISO 2852 2 in, 76.2 face to face | Type B gaskets, 2 in clamps | clamp | all |
| finished bore | Ø48.00 through, honed | Ø48.00 clearance-seal piston (no rings) | run | all |

## Sizes

| feature | value |
|---|---|
| faces | ISO 2852 2 in, 76.2 face to face |
| finished bore | Ø48.00 through, honed |
| piston | Ø48.00 × 34 |
| stroke | 36.0 |

## Where the files are

- ISO (via iTeh sample): [ISO 2852 clamp liners: face profile and flange / groove diameters](https://cdn.standards.iteh.ai/samples/7850/eb49c396488d408c8ced3e2961d76cf3/ISO-2852-1974.pdf) — PDF — standard excerpt; dimensions are facts
- ASME: [BPE Bioprocessing Equipment (clamp fitting dimensions, tube OD and wall)](https://www.asme.org/codes-standards/find-codes-standards/bpe-bioprocessing-equipment) — standard — ASME; dimensions are facts (verify at link)
- Long Earth Society: [Engine builds](https://longearthsociety.com/engineering/) — web, video — LES site

## Free STEP/STL (1 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/tri-clamp-spool-bored-honed/index.json

- spool-2in-3in-bored-48.00: [STEP](https://xemstudio.com/files/hardware/tri-clamp-spool-bored-honed/spool-2in-3in-bored-48.00.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-spool-bored-honed/spool-2in-3in-bored-48.00.stl) — 2 in × 3 in (76.2) spool, ISO 2852 faces, bore finished Ø48.00 through (honed: the piston's clearance seal)

## Questions

**Does it need rings?**

No: the piston is a clearance seal. Its leakage loss is in the engine's numbers for 10, 15 and 20 µm radial clearance.

## Fits with

- [Clearance-seal pistons Ø48.00 × 34 for a bored 2 in spool: rod (gamma) and gland (beta)](https://xemstudio.com/objects/stirling-clearance-seal-pistons/)
- [2 in × 152.4 mm closed-end hot spool, bore finished Ø48.00](https://xemstudio.com/objects/tri-clamp-closed-hot-spool-bored/)
- [Build list: Tri-clamp horizontal gamma generator, 2 in, chargeable](https://xemstudio.com/objects/list-tri-clamp-horizontal-gamma/)
- [Build list: Tri-clamp charged beta, 2 in](https://xemstudio.com/objects/list-tri-clamp-charged-beta/)