Water tray for a 10 in cold cap (optional) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/htd-water-tray-10in/  (CC BY 4.0)
Basis: Exact geometry
Catalog version: 2026-10-20

Sizes: see table below
- A separate heat exchanger, optional: an open ring tray that sits on the cold cap's flat top round the 2 in ferrule and holds water. The cap takes about the cup wall's leak plus the engine's rejected heat (a few hundred watts at full fire), so the water warms and has to be topped up; ice water helps. The engine runs without it, hotter on the cold side.

id_mm  od_mm  height_mm
118.0  190.0  40.0

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Long Earth Society: Engine builds — web, video — LES site — https://longearthsociety.com/engineering/

Free files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/htd-water-tray-10in/index.json
API: https://xemstudio.com/api/geometry?object=htd-water-tray-10in