# Build list: Tri-clamp tee diaphragm gamma, 2 in

> What parts do I need to build a Tri-clamp tee diaphragm gamma, 2 in?

- Category: Stirling engines › Guide
- Kind: List / guide
- Basis: Every part is a free STEP/STL on this site or a standard part with its own page; quantities are the full count, every screw, nut, pin, gasket and clamp.
- Page: https://xemstudio.com/objects/list-tri-clamp-tee-diaphragm-gamma/ · JSON: https://xemstudio.com/api/geometry?object=list-tri-clamp-tee-diaphragm-gamma · Plain text: https://xemstudio.com/objects/list-tri-clamp-tee-diaphragm-gamma/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses

**Exact dimensions.** True size, with no printing tolerance added.

## Notes

- A tea-light gamma in 2 in tri-clamp: displacer in a 3 in spool, a short-outlet tee with a diaphragm head as the power piston, a rocker beam and one crank pin at 90°.
- Numbers: Ø46 × 120 displacer at 15 mm stroke · 2 in diaphragm at 15 mm: 14.2 mL swept · dead volume 118 mL with the filler (289 without) · swept / dead 0.120

## Sizes

| subsystem | object | parts | qty | note |
|---|---|---|---|---|
| None | tri-clamp-diaphragm-gamma-frame | gamma-frame-2in | 1 | base, column ring, tower, crank shelf, pivot bracket |
| None | tea-light-candles | tea-light-38x16 | 1 | inside the column ring, 17.5 below the hot cap |
| None | tri-clamp-end-cap | tc-cap-2in-flat | 1 | hot end, face up on the column ring |
| None | tri-clamp-hot-gasket | hot-gasket-2in | 1 | hot joint |
| None | tri-clamp-heat-shield | heat-shield-2in | 1 | on the spool above the hot clamp |
| None | tri-clamp-spool | tc-spool-2in-3in | 1 | displacer cylinder, Ø47.5 bore |
| None | tri-clamp-gasket | tc-gasket-2in | 2 | spool–tee and tee–head joints |
| None | sanitary-clamp-tees | tee-short-2in | 1 | short-outlet tee, run vertical, branch to the diaphragm |
| None | tri-clamp-displacer-head | head-displacer-2in | 1 | top: Ø3 rod guide; its barb is plugged |
| None | silicone-tube | silicone-tube-4x6-50 | 1 | on the head barb, closed by the dowel |
| None | dowel-pins-metric | dowel-4x12 | 1 | plug in the silicone tube |
| None | tri-clamp-volume-filler | plug-tee-2in-rod-106.55 | 1 | fills the tee run above the displacer; Ø12 passage for the rod |
| None | tri-clamp-clamps | clamp-half-2in | 8 | four joints, two halves each |
| None | socket-head-cap-screws-metric | shcs-m5x30 | 8 | clamp bolts |
| None | hex-nuts-metric | nut-m5 | 8 | clamp nuts, in the hex traps |
| None | tri-clamp-displacer | displacer-shell-2in-120 | 1 | Ø46 × 120, 0.75 radial gap, 15 stroke |
| None | tri-clamp-displacer | displacer-cap-2in | 1 | closes the shell, holds the rod |
| None | displacer-rods | rod-3x200 | 1 | displacer rod |
| None | tri-clamp-diaphragm-head | diaphragm-head-2in | 1 | on the tee branch: the power diaphragm |
| None | tri-clamp-diaphragm-membrane | membrane-2in | 1 | clamped in place of the gasket |
| None | tri-clamp-diaphragm-disc | diaphragm-disc-2in | 1 | head side of the membrane, carries the rod |
| None | tri-clamp-diaphragm-disc | diaphragm-backing-2in | 1 | gas side of the membrane |
| None | socket-head-cap-screws-metric | shcs-m2x8 | 3 | through backing disc, membrane and centre disc |
| None | hex-nuts-metric | nut-m2 | 3 | on the centre disc |
| None | displacer-rods | rod-3x100 | 1 | diaphragm rod |
| None | displacer-rods | rod-3x150 | 1 | pushrod, beam to crank |
| None | rod-clevises | rod-clevis-3mm | 4 | displacer rod, diaphragm rod, both pushrod ends |
| None | connecting-rods-623 | conrod-30 | 1 | displacer rod to beam |
| None | connecting-rods-623 | conrod-60 | 1 | diaphragm rod to crank pin |
| None | ball-bearings-metric | bearing-623 | 5 | both con-rods' eyes and the beam pivot |
| None | rocker-beam | rocker-beam-100 | 1 | 1:1 beam, displacer 15 stroke |
| None | beam-pivot-post | pivot-post-60 | 1 | on the frame bracket |
| None | dowel-pins-metric | dowel-3x12 | 1 | beam end A with the con-rod beside it |
| None | dowel-pins-metric | dowel-3x16 | 1 | beam pivot through the post and the beam's 623 |
| None | dowel-pins-metric | dowel-3x20 | 2 | beam end B with the upper pushrod clevis; diaphragm clevis with its con-rod beside it |
| None | dowel-pins-metric | dowel-3x30 | 2 | crank pin (lower pushrod clevis and diaphragm con-rod); displacer clevis pin (con-rod 12 mm beside the clevis) |
| None | counterweighted-crank-discs | cw-crank-disc-stroke15 | 1 | one pin: diaphragm con-rod and pushrod, 90° lines of action |
| None | stirling-crankshafts | crankshaft-5x100-dflat | 1 |  |
| None | crank-stands-625 | crank-stand-625-h60 | 2 | on the frame shelf |
| None | ball-bearings-metric | bearing-625 | 2 | one per stand |
| None | shaft-collars | collar-5mm | 1 | outside the far stand |
| None | nut-pocket-flywheels | flywheel-150-m10-b5 | 1 | between the crank disc and the stands |
| None | hex-nut-weights | nut-m10 | 18 | one in each rim pocket |
| None | set-screws-metric | set-m3x4 | 9 | grubs: displacer cap, diaphragm disc, 4 clevises, crank disc, collar, flywheel |
| None | socket-head-cap-screws-metric | shcs-m3x16 | 6 | crank stands (4) and pivot post (2) to the frame |
| None | hex-nuts-metric | nut-m3 | 6 | under the shelf and bracket |

## Where the files are

- Long Earth Society: [Engine builds](https://longearthsociety.com/engineering/) — web, video — LES site

## Build order

1. Frame on the bench; tea light in the column ring; hot cap face up on the ring.
2. Hot gasket, 3 in spool, clamp; heat shield on the spool above the hot clamp.
3. Displacer shell and cap with the Ø3 × 200 rod in the cap's grub; displacer into the spool.
4. Type B gasket, short-outlet tee (branch toward the crank side), clamp; tee-run plug down over the rod onto the gasket lip; Type B gasket, displacer head, clamp; silicone tube and dowel plug on the head barb.
5. Diaphragm: backing disc, membrane, centre disc with three M2 × 8 and nuts; Ø3 × 100 rod in the boss; membrane on the tee branch, head over the rod, clamp.
6. Crank stands on the shelf; crankshaft, flywheel with its nuts, crank disc; pivot post on the bracket; beam on its 623.
7. Con-rod 30 between the displacer clevis and beam end A; pushrod (Ø3 × 150, two clevises) from beam end B to the crank pin; con-rod 60 from the diaphragm clevis to the crank pin.

All printed STLs: https://xemstudio.com/objects/list-tri-clamp-tee-diaphragm-gamma/stl-list.txt

## Questions

**What parts do I need for the tri-clamp tee diaphragm gamma?**

46 parts, every one a free STEP/STL on this site; see the table and the build order on this page.

**Why a diaphragm instead of a piston?**

A clamped membrane has no sliding seal: no piston fit, no friction at the seal, and it seals as well as a gasket.

## Fits with

- [Tri-clamp diaphragm head: 1.5 and 2 in, membrane in place of the gasket](https://xemstudio.com/objects/tri-clamp-diaphragm-head/)
- [Tri-clamp diaphragm membrane: flat, 1.5 and 2 in clamped size](https://xemstudio.com/objects/tri-clamp-diaphragm-membrane/)
- [Tri-clamp diaphragm centre disc and backing disc: 1.5 and 2 in](https://xemstudio.com/objects/tri-clamp-diaphragm-disc/)
- [Tri-clamp volume fillers: 2 in tee-run plugs and annular sleeves](https://xemstudio.com/objects/tri-clamp-volume-filler/)
- [Frame for the 2 in tri-clamp tee diaphragm gamma](https://xemstudio.com/objects/tri-clamp-diaphragm-gamma-frame/)
- [Sanitary clamp tees and short-outlet tees (7MP, 7MPS): ½ to 4 in](https://xemstudio.com/objects/sanitary-clamp-tees/)
- [Tri-clamp displacer: Ø33.6, Ø46 and Ø70.9 for 1.5, 2 and 3 in spools](https://xemstudio.com/objects/tri-clamp-displacer/)
- [Rocker beam 60 / 80 / 100 mm on a 623 pivot](https://xemstudio.com/objects/rocker-beam/)
- [Build list: Gamma Stirling, 2 in tri-clamp](https://xemstudio.com/objects/list-gamma-2in-tri-clamp/)