{
 "version": "2026-10-20",
 "license": "Dimension sheets are written by Xem Studio from the cited sources and are free to use (CC BY 4.0, attribute 'Xem Studio'). Linked files belong to their publishers under the license shown; Xem Studio does not host them. 'license_verified: false' means the license shown is from memory or the publisher's page as last read and should be confirmed at the link before commercial use.",
 "slug": "list-tri-clamp-charged-beta",
 "name": "Build list: Tri-clamp charged beta, 2 in",
 "kind": "list",
 "category": "Stirling engines",
 "group": "Guide",
 "year": null,
 "question": "What parts do I need to build a Tri-clamp charged beta, 2 in?",
 "tags": [
  "list",
  "build",
  "stirling",
  "long earth society",
  "tri-clamp",
  "diaphragm",
  "beta",
  "piston",
  "pressurised",
  "helium",
  "torch"
 ],
 "aliases": [
  "pressurised stirling engine tri clamp",
  "beta stirling engine piston",
  "helium stirling engine build",
  "tri clamp crankcase",
  "stirling engine build list"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "not-scanned",
 "les": true,
 "free_files": 0,
 "url": "https://xemstudio.com/objects/list-tri-clamp-charged-beta/",
 "sheet_txt": "https://xemstudio.com/objects/list-tri-clamp-charged-beta/sheet.txt",
 "sheet": {
  "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.",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "A standing beta that holds a charge: the same hot spool, liner, regenerator and displacer as the horizontal gamma, the bored power spool directly above them, coaxial rods, and a 3 in tee as a sealed crankcase with a shaft seal on the output.",
   "Numbers: Displacer Ø40 × 30 (37.7 mL) · piston Ø48 × 36 (64.1 mL net of the Ø6 rod) · 90° · dead 66.2 mL (swept/dead 0.97) · charge 5 bar gauge, relief 7 · crankcase buffer 1.52 L · model shaft power: air 17–40 W at 600 rpm, helium 36–82 W at 1200 rpm"
  ],
  "table": {
   "columns": [
    "subsystem",
    "object",
    "parts",
    "qty",
    "note"
   ],
   "rows": [
    [
     null,
     "tri-clamp-charged-beta-frame",
     "charged-beta-frame-2in",
     1,
     "base, wall, gussets"
    ],
    [
     null,
     "tri-clamp-torch-stand",
     "torch-stand-40",
     1,
     "under the hot spool, post toward +Y"
    ],
    [
     null,
     "set-screws-metric",
     "set-m4x10",
     3,
     "centre the torch head in the stand ring"
    ],
    [
     null,
     "socket-head-cap-screws-metric",
     "shcs-m4x10",
     5,
     "torch stand (2), shroud feet (3)"
    ],
    [
     null,
     "tri-clamp-burner-shroud",
     "burner-shroud-2in",
     1,
     "round the fins"
    ],
    [
     null,
     "tri-clamp-closed-hot-spool-bored",
     "hot-spool-2in-152.4-closed-bored-48.00",
     1,
     "face up, closed end in the shroud"
    ],
    [
     null,
     "tri-clamp-ring-fin-sleeve",
     "fin-sleeve-2in-9x76",
     1,
     "optional heat exchanger: slid over the closed end"
    ],
    [
     null,
     "tri-clamp-flow-water-jacket",
     "water-jacket-half-2in-48-flow",
     2,
     "optional heat exchanger: round the cold end over the cooler zone, hose spigots toward ±Y"
    ],
    [
     null,
     "socket-head-cap-screws-metric",
     "shcs-m4x25",
     4,
     "optional: water-jacket ears"
    ],
    [
     null,
     "hex-nuts-metric",
     "nut-m4",
     4,
     "optional: water-jacket ears"
    ],
    [
     null,
     "stirling-annular-screen-stack",
     "screen-stack-48x42x40-50mesh",
     1,
     "optional heat exchanger (with the liner): on the liner's neck"
    ],
    [
     null,
     "stirling-slotted-regenerator-liner",
     "liner-2in-slotted-48-40",
     1,
     "optional heat exchanger (internal insert), pressed into the hot spool: without it the displacer runs in the Ø48.00 bore 4 mm clear, a plain annular-gap engine with far less power"
    ],
    [
     null,
     "stirling-clearance-seal-displacer",
     "displacer-shell-38.5x98",
     1,
     "the shell"
    ],
    [
     null,
     "stirling-clearance-seal-displacer",
     "displacer-cap-40-land",
     1,
     "pressed into the shell; land in the liner bore"
    ],
    [
     null,
     "stirling-precision-rods",
     "rod-6x300.25-m6",
     1,
     "displacer rod: up through the piston's gland and the hollow rod"
    ],
    [
     null,
     "hex-nuts-metric",
     "nut-m6",
     2,
     "lock nuts: displacer cold face, under the displacer yoke"
    ],
    [
     null,
     "tri-clamp-spool-bored-honed",
     "spool-2in-3in-bored-48.00",
     1,
     "power cylinder, on the hot spool"
    ],
    [
     null,
     "stirling-clearance-seal-pistons",
     "piston-48-beta-gland",
     1,
     "Ø48.00, gland at the crown"
    ],
    [
     null,
     "sleeve-bushings",
     "bushing-6x10x10",
     2,
     "piston gland, top of the hollow-rod yoke"
    ],
    [
     null,
     "stirling-precision-rods",
     "tube-10x7x158.6-m10x1",
     1,
     "hollow piston rod"
    ],
    [
     null,
     "tri-clamp-guide-plate",
     "guide-plate-2in-10mm",
     1,
     "between the power spool and the reducer"
    ],
    [
     null,
     "sleeve-bushings",
     "bushing-10x14x15",
     2,
     "in the guide plate"
    ],
    [
     null,
     "sanitary-clamp-reducers",
     "reducer-concentric-3inx2in",
     1,
     "2 in end down on the guide plate"
    ],
    [
     null,
     "sanitary-clamp-tees",
     "tee-3in",
     1,
     "the crankcase: branch down, run along the crankshaft"
    ],
    [
     null,
     "tri-clamp-bearing-cap-3in",
     "bearing-cap-3in-608-seal",
     1,
     "+X: bearing and shaft seal, the output side"
    ],
    [
     null,
     "tri-clamp-bearing-cap-3in",
     "bearing-cap-3in-608-3x-npt14",
     1,
     "−X: bearing; fill, gauge and relief ports"
    ],
    [
     null,
     "rotary-shaft-seal-8x22x7",
     "shaft-seal-8x22x7",
     1,
     "in the +X cap, lip toward the crankcase"
    ],
    [
     null,
     "ball-bearings-metric",
     "bearing-608",
     2,
     "one in each cap"
    ],
    [
     null,
     "high-pressure-sanitary-clamps",
     "hp-clamp-2in",
     3,
     "hot–power spool, power spool–plate, plate–reducer; rating above the 7 bar gauge relief setting (not drawn here)"
    ],
    [
     null,
     "high-pressure-sanitary-clamps",
     "hp-clamp-3in",
     3,
     "reducer–tee, tee–caps; rating above the 7 bar gauge relief setting (not drawn here)"
    ],
    [
     null,
     "tri-clamp-gasket",
     "tc-gasket-2in",
     3,
     "the three 2 in joints"
    ],
    [
     null,
     "sanitary-clamp-gaskets",
     "gasket-3in",
     3,
     "the three 3 in joints"
    ],
    [
     null,
     "npt-thread-envelopes",
     "npt-1-4-male",
     3,
     "1/4 NPT stems: crankcase fill, gauge, relief (bodies are the builder's choice)"
    ],
    [
     null,
     "stirling-crosshead-yokes",
     "yoke-tube10-m10x1",
     1,
     "on the hollow rod, stub pin toward −X"
    ],
    [
     null,
     "stirling-crosshead-yokes",
     "yoke-rod6-m6",
     1,
     "on the displacer rod, stub pin toward +X"
    ],
    [
     null,
     "dowel-pins-metric",
     "dowel-5x20",
     2,
     "stub wrist pins"
    ],
    [
     null,
     "shaft-collars",
     "collar-5mm",
     2,
     "on the wrist pins"
    ],
    [
     null,
     "set-screws-metric",
     "set-m3x4",
     2,
     "wrist-pin collars"
    ],
    [
     null,
     "stirling-conrods-626-625",
     "conrod-626-625-120",
     1,
     "piston"
    ],
    [
     null,
     "stirling-conrods-626-625",
     "conrod-626-625-55",
     1,
     "displacer"
    ],
    [
     null,
     "ball-bearings-metric",
     "bearing-626",
     2,
     "big ends"
    ],
    [
     null,
     "ball-bearings-metric",
     "bearing-625",
     2,
     "small ends"
    ],
    [
     null,
     "stirling-built-up-crank-webs",
     "crank-web-56x8-r18",
     1,
     "−X web, piston pin"
    ],
    [
     null,
     "stirling-built-up-crank-webs",
     "link-web-14-r18-r15-90",
     1,
     "between the con-rods: piston pin and displacer pin"
    ],
    [
     null,
     "stirling-built-up-crank-webs",
     "crank-web-56x8-r15",
     1,
     "+X web, displacer pin"
    ],
    [
     null,
     "dowel-pins-metric",
     "dowel-6x30",
     2,
     "crank pins"
    ],
    [
     null,
     "stirling-precision-rods",
     "shaft-8x103.95",
     1,
     "−X crank stub"
    ],
    [
     null,
     "stirling-precision-rods",
     "shaft-8x138.3",
     1,
     "+X crank stub: through the seal to the flywheel"
    ],
    [
     null,
     "shaft-collars",
     "collar-8mm",
     2,
     "inside the bearings: axial location"
    ],
    [
     null,
     "set-screws-metric",
     "set-m4x4",
     2,
     "8 mm collars"
    ],
    [
     null,
     "nut-pocket-flywheels",
     "flywheel-200-m12-b8",
     1,
     "outside the +X cap"
    ],
    [
     null,
     "hex-nut-weights",
     "nut-m12",
     18,
     "one in each rim pocket"
    ],
    [
     null,
     "set-screws-metric",
     "set-m3x6",
     1,
     "flywheel hub"
    ],
    [
     null,
     "spool-hanger-collars",
     "hanger-2in-tab",
     2,
     "on the power spool, bars to the wall"
    ],
    [
     null,
     "spool-hanger-collars",
     "hanger-2in-plain",
     2,
     "close the hangers"
    ],
    [
     null,
     "socket-head-cap-screws-metric",
     "shcs-m4x20",
     4,
     "hanger ears"
    ],
    [
     null,
     "hex-nuts-metric",
     "nut-m4",
     4,
     "hanger ears"
    ],
    [
     null,
     "socket-head-cap-screws-metric",
     "shcs-m5x25",
     4,
     "hanger bars through the wall"
    ],
    [
     null,
     "hex-nuts-metric",
     "nut-m5",
     4,
     "hanger bars"
    ]
   ]
  }
 },
 "sheet_text": "Build list: Tri-clamp charged beta, 2 in — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/list-tri-clamp-charged-beta/  (CC BY 4.0)\nBasis: 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.\nCatalog version: 2026-10-20\n\nSizes: see table below\n- A standing beta that holds a charge: the same hot spool, liner, regenerator and displacer as the horizontal gamma, the bored power spool directly above them, coaxial rods, and a 3 in tee as a sealed crankcase with a shaft seal on the output.\n- Numbers: Displacer Ø40 × 30 (37.7 mL) · piston Ø48 × 36 (64.1 mL net of the Ø6 rod) · 90° · dead 66.2 mL (swept/dead 0.97) · charge 5 bar gauge, relief 7 · crankcase buffer 1.52 L · model shaft power: air 17–40 W at 600 rpm, helium 36–82 W at 1200 rpm\n\nsubsystem  object  parts  qty  note\nNone  tri-clamp-charged-beta-frame  charged-beta-frame-2in  1  base, wall, gussets\nNone  tri-clamp-torch-stand  torch-stand-40  1  under the hot spool, post toward +Y\nNone  set-screws-metric  set-m4x10  3  centre the torch head in the stand ring\nNone  socket-head-cap-screws-metric  shcs-m4x10  5  torch stand (2), shroud feet (3)\nNone  tri-clamp-burner-shroud  burner-shroud-2in  1  round the fins\nNone  tri-clamp-closed-hot-spool-bored  hot-spool-2in-152.4-closed-bored-48.00  1  face up, closed end in the shroud\nNone  tri-clamp-ring-fin-sleeve  fin-sleeve-2in-9x76  1  optional heat exchanger: slid over the closed end\nNone  tri-clamp-flow-water-jacket  water-jacket-half-2in-48-flow  2  optional heat exchanger: round the cold end over the cooler zone, hose spigots toward ±Y\nNone  socket-head-cap-screws-metric  shcs-m4x25  4  optional: water-jacket ears\nNone  hex-nuts-metric  nut-m4  4  optional: water-jacket ears\nNone  stirling-annular-screen-stack  screen-stack-48x42x40-50mesh  1  optional heat exchanger (with the liner): on the liner's neck\nNone  stirling-slotted-regenerator-liner  liner-2in-slotted-48-40  1  optional heat exchanger (internal insert), pressed into the hot spool: without it the displacer runs in the Ø48.00 bore 4 mm clear, a plain annular-gap engine with far less power\nNone  stirling-clearance-seal-displacer  displacer-shell-38.5x98  1  the shell\nNone  stirling-clearance-seal-displacer  displacer-cap-40-land  1  pressed into the shell; land in the liner bore\nNone  stirling-precision-rods  rod-6x300.25-m6  1  displacer rod: up through the piston's gland and the hollow rod\nNone  hex-nuts-metric  nut-m6  2  lock nuts: displacer cold face, under the displacer yoke\nNone  tri-clamp-spool-bored-honed  spool-2in-3in-bored-48.00  1  power cylinder, on the hot spool\nNone  stirling-clearance-seal-pistons  piston-48-beta-gland  1  Ø48.00, gland at the crown\nNone  sleeve-bushings  bushing-6x10x10  2  piston gland, top of the hollow-rod yoke\nNone  stirling-precision-rods  tube-10x7x158.6-m10x1  1  hollow piston rod\nNone  tri-clamp-guide-plate  guide-plate-2in-10mm  1  between the power spool and the reducer\nNone  sleeve-bushings  bushing-10x14x15  2  in the guide plate\nNone  sanitary-clamp-reducers  reducer-concentric-3inx2in  1  2 in end down on the guide plate\nNone  sanitary-clamp-tees  tee-3in  1  the crankcase: branch down, run along the crankshaft\nNone  tri-clamp-bearing-cap-3in  bearing-cap-3in-608-seal  1  +X: bearing and shaft seal, the output side\nNone  tri-clamp-bearing-cap-3in  bearing-cap-3in-608-3x-npt14  1  −X: bearing; fill, gauge and relief ports\nNone  rotary-shaft-seal-8x22x7  shaft-seal-8x22x7  1  in the +X cap, lip toward the crankcase\nNone  ball-bearings-metric  bearing-608  2  one in each cap\nNone  high-pressure-sanitary-clamps  hp-clamp-2in  3  hot–power spool, power spool–plate, plate–reducer; rating above the 7 bar gauge relief setting (not drawn here)\nNone  high-pressure-sanitary-clamps  hp-clamp-3in  3  reducer–tee, tee–caps; rating above the 7 bar gauge relief setting (not drawn here)\nNone  tri-clamp-gasket  tc-gasket-2in  3  the three 2 in joints\nNone  sanitary-clamp-gaskets  gasket-3in  3  the three 3 in joints\nNone  npt-thread-envelopes  npt-1-4-male  3  1/4 NPT stems: crankcase fill, gauge, relief (bodies are the builder's choice)\nNone  stirling-crosshead-yokes  yoke-tube10-m10x1  1  on the hollow rod, stub pin toward −X\nNone  stirling-crosshead-yokes  yoke-rod6-m6  1  on the displacer rod, stub pin toward +X\nNone  dowel-pins-metric  dowel-5x20  2  stub wrist pins\nNone  shaft-collars  collar-5mm  2  on the wrist pins\nNone  set-screws-metric  set-m3x4  2  wrist-pin collars\nNone  stirling-conrods-626-625  conrod-626-625-120  1  piston\nNone  stirling-conrods-626-625  conrod-626-625-55  1  displacer\nNone  ball-bearings-metric  bearing-626  2  big ends\nNone  ball-bearings-metric  bearing-625  2  small ends\nNone  stirling-built-up-crank-webs  crank-web-56x8-r18  1  −X web, piston pin\nNone  stirling-built-up-crank-webs  link-web-14-r18-r15-90  1  between the con-rods: piston pin and displacer pin\nNone  stirling-built-up-crank-webs  crank-web-56x8-r15  1  +X web, displacer pin\nNone  dowel-pins-metric  dowel-6x30  2  crank pins\nNone  stirling-precision-rods  shaft-8x103.95  1  −X crank stub\nNone  stirling-precision-rods  shaft-8x138.3  1  +X crank stub: through the seal to the flywheel\nNone  shaft-collars  collar-8mm  2  inside the bearings: axial location\nNone  set-screws-metric  set-m4x4  2  8 mm collars\nNone  nut-pocket-flywheels  flywheel-200-m12-b8  1  outside the +X cap\nNone  hex-nut-weights  nut-m12  18  one in each rim pocket\nNone  set-screws-metric  set-m3x6  1  flywheel hub\nNone  spool-hanger-collars  hanger-2in-tab  2  on the power spool, bars to the wall\nNone  spool-hanger-collars  hanger-2in-plain  2  close the hangers\nNone  socket-head-cap-screws-metric  shcs-m4x20  4  hanger ears\nNone  hex-nuts-metric  nut-m4  4  hanger ears\nNone  socket-head-cap-screws-metric  shcs-m5x25  4  hanger bars through the wall\nNone  hex-nuts-metric  nut-m5  4  hanger bars\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Long Earth Society: Engine builds — web, video — LES site — https://longearthsociety.com/engineering/\n\nXem Studio scan: not planned; the official CAD above covers it.\nAPI: https://xemstudio.com/api/geometry?object=list-tri-clamp-charged-beta\n",
 "sources": [
  {
   "publisher": "Long Earth Society",
   "title": "Engine builds",
   "url": "https://longearthsociety.com/engineering/",
   "formats": [
    "web",
    "video"
   ],
   "license": "LES site",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "not-scanned",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "tri-clamp-closed-hot-spool-bored",
  "tri-clamp-guide-plate",
  "tri-clamp-bearing-cap-3in",
  "rotary-shaft-seal-8x22x7",
  "list-tri-clamp-horizontal-gamma",
  "list-tri-clamp-sealed-diaphragm-generator"
 ],
 "fits": [],
 "dimensions": "exact (nominal, no printing tolerance)",
 "dimension_rule": "All geometry on Xem Studio is exact (nominal, true size) with no printing tolerance. Where a part meets another part, the object lists its mating features (feature, exact size, what it mates with, fit class: press, slide, run, socket, clamp or designed). Apply your process's allowance to those features only; 'designed' gaps are part of the design and stay as drawn.",
 "mating": [],
 "faq": [
  {
   "q": "How much power?",
   "a": "In the model at 5 bar gauge: 17–40 W on air at 600 rpm, 36–82 W on helium at 1200 rpm."
  },
  {
   "q": "Why helium?",
   "a": "It carries heat about six times better and flows with less loss, so the same engine runs faster on it."
  },
  {
   "q": "Where can it leak?",
   "a": "At the shaft seal, and through the piston's clearance and the gland only between working space and crankcase (both charged). Keep the fill valve on a regulated supply."
  },
  {
   "q": "What are the clamps?",
   "a": "High-pressure bolted sanitary clamps on every joint, rated above the relief setting."
  }
 ],
 "files_license": null,
 "offers": [],
 "markdown": "https://xemstudio.com/objects/list-tri-clamp-charged-beta/index.md"
}