# Torch stand for a horizontal tri-clamp hot leg

> How do I hold a torch under a Stirling engine's hot end?

- Category: Hardware › Stirling & thermoacoustic
- Kind: Hardware
- Basis: Design values; ISO 273 clearance for the M4 foot screws
- Page: https://xemstudio.com/objects/tri-clamp-torch-stand/ · JSON: https://xemstudio.com/api/geometry?object=tri-clamp-torch-stand · Plain text: https://xemstudio.com/objects/tri-clamp-torch-stand/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses

**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 foot, a post and a ring: the torch head goes up through the Ø32 ring and three M4 set screws centre it, so the flame points straight up at the middle of the hot leg.
- The post stands to one side so the space under the ring is open. The foot bolts to the engine frame with two M4 screws.

## 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 |
|---|---|---|---|---|
| ring bore | Ø32 | torch head (centred by the set screws) | designed | torch-stand-* |
| set-screw holes | 3 × Ø3.3 | M4 tap drill | designed | torch-stand-* |
| foot holes | 2 × Ø4.5 | M4 clearance (ISO 273 medium) | designed | torch-stand-* |

## Sizes

| part | size_mm |
|---|---|
| foot | 70 × 40 × 5 |
| ring | Ø48 / Ø32 × 14 |
| ring top above foot | 40 |

## Where the files are

- ISO: [ISO 273 clearance holes for bolts and screws (fine / medium / coarse)](https://www.iso.org/standard/4196.html) — standard — 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-torch-stand/index.json

- torch-stand-40: [STEP](https://xemstudio.com/files/hardware/tri-clamp-torch-stand/torch-stand-40.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-torch-stand/torch-stand-40.stl) — torch stand: foot 70 × 40 × 5 with 2 × Ø4.5 at ±25, post 14 × 14, ring Ø48 / Ø32 × 14, ring top 40 above the foot, 3 × M4 tapped (Ø3.3) at 120°

## Questions

**What torch fits?**

Any torch head that passes the Ø32 ring; the three set screws centre it.

## Fits with

- [Build list: Tri-clamp elbow diaphragm alpha, 2 in](https://xemstudio.com/objects/list-tri-clamp-elbow-diaphragm-alpha/)
- [Frame for the 2 in tri-clamp elbow diaphragm alpha](https://xemstudio.com/objects/tri-clamp-diaphragm-alpha-frame/)