{
 "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": "tri-clamp-bubble-counters",
 "name": "Optical bubble counter for a blow-off line: 5 mm LED break-beam, ¼ in barbs",
 "kind": "hardware",
 "category": "Hardware",
 "group": "Sanitary clamp fittings",
 "year": null,
 "question": "How do I count fermentation bubbles electronically?",
 "tags": [
  "bubble counter",
  "airlock",
  "co2",
  "fermentation activity",
  "esp32",
  "ir sensor",
  "sanitary",
  "tri-clamp",
  "clamp fitting",
  "brewing",
  "homebrew"
 ],
 "aliases": [
  "airlock bubble counter",
  "fermentation bubble counter 3d print",
  "blow off bubble sensor",
  "esp32 bubble counter"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/tri-clamp-bubble-counters/",
 "sheet_txt": "https://xemstudio.com/objects/tri-clamp-bubble-counters/sheet.txt",
 "sheet": {
  "basis": "Xem Studio design: a small water-filled chamber on the blow-off line; each bubble rising from the inlet tube crosses a beam between a 5 mm IR LED and a 5 mm phototransistor in two Ø5.1 holes",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Run the blow-off hose from the lid barb (through a ½ × ¼ in reducing hose or a ¼ in barb port) into the inlet barb; fill the chamber about 35 mm deep with water or sanitiser so the beam (22 mm up) is under water. Each bubble breaks the beam once: count pulses on an ESP32 input to log the CO₂ rate.",
   "Print it in a clear material, or seal the LED holes with clear epoxy; mount it upright with two M3 screws through the base.",
   "Every clamp face is the ISO 2852 profile used across this site: 2.85 mm rim, flat face with the gasket groove (K 1.6 deep, R3 1.2 bottom, 23° walls, P2 0.8 edges) on C2, 20° back cone. Flange C3 / groove C2 / tube OD × wall, mm: ½–¾ in 25.0 / 20.4 (derived) / 12.7–19.05 × 1.65; 1–1½ in 50.5 / 43.5 / 25.4–38.1 × 1.65; 2 in 64.0 / 56.5 / 50.8 × 1.65; 2½ in 77.5 / 70.5 / 63.5 × 1.65; 3 in 91.0 / 83.5 / 76.2 × 1.65; 4 in 119.0 / 110.0 / 101.6 × 2.11; 6 in 166.9 (6.570 in) / 156.5 / 152.4 × 2.77; 8 in 217.7 (8.570 in) / 207.0 / 203.2 × 2.77; 10 in 268.5 / 261.0 / 254.0 × 3.40; 12 in 319.3 / 311.8 / 304.8 × 3.40."
  ],
  "table": {
   "columns": [
    "chamber_bore_mm",
    "chamber_h_mm",
    "beam_height_mm",
    "led_hole_mm",
    "barbs"
   ],
   "rows": [
    [
     24,
     70,
     22,
     5.1,
     "¼ in in / out"
    ]
   ]
  }
 },
 "sheet_text": "Optical bubble counter for a blow-off line: 5 mm LED break-beam, ¼ in barbs — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/tri-clamp-bubble-counters/  (CC BY 4.0)\nBasis: Xem Studio design: a small water-filled chamber on the blow-off line; each bubble rising from the inlet tube crosses a beam between a 5 mm IR LED and a 5 mm phototransistor in two Ø5.1 holes\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Run the blow-off hose from the lid barb (through a ½ × ¼ in reducing hose or a ¼ in barb port) into the inlet barb; fill the chamber about 35 mm deep with water or sanitiser so the beam (22 mm up) is under water. Each bubble breaks the beam once: count pulses on an ESP32 input to log the CO₂ rate.\n- Print it in a clear material, or seal the LED holes with clear epoxy; mount it upright with two M3 screws through the base.\n- Every clamp face is the ISO 2852 profile used across this site: 2.85 mm rim, flat face with the gasket groove (K 1.6 deep, R3 1.2 bottom, 23° walls, P2 0.8 edges) on C2, 20° back cone. Flange C3 / groove C2 / tube OD × wall, mm: ½–¾ in 25.0 / 20.4 (derived) / 12.7–19.05 × 1.65; 1–1½ in 50.5 / 43.5 / 25.4–38.1 × 1.65; 2 in 64.0 / 56.5 / 50.8 × 1.65; 2½ in 77.5 / 70.5 / 63.5 × 1.65; 3 in 91.0 / 83.5 / 76.2 × 1.65; 4 in 119.0 / 110.0 / 101.6 × 2.11; 6 in 166.9 (6.570 in) / 156.5 / 152.4 × 2.77; 8 in 217.7 (8.570 in) / 207.0 / 203.2 × 2.77; 10 in 268.5 / 261.0 / 254.0 × 3.40; 12 in 319.3 / 311.8 / 304.8 × 3.40.\n\nchamber_bore_mm  chamber_h_mm  beam_height_mm  led_hole_mm  barbs\n24  70  22  5.1  ¼ in in / out\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- GW Kent: Tri-clamp fittings guide: tube OD, flange OD and ID per size to 12 in; solid cap thickness — web — publisher's guide; dimensions cited — https://www.gwkent.com/triclamp-guide\n- Rubber Fab: Tri-Clamp gasket dimensional chart: gasket ID, OD and bead diameter per size (2 in bead 2.22 in / 56.50 mm, 1.5 in 1.71 / 43.50, 3 in 3.29 / 83.50) — PDF — maker chart; dimensions are facts [verify license at link] — https://shop.andersonprocess.com/media/assets/product/documents/rubber-fab-tri-clamp-dimensions.pdf\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/tri-clamp-bubble-counters/index.json\nAPI: https://xemstudio.com/api/geometry?object=tri-clamp-bubble-counters\n",
 "sources": [
  {
   "publisher": "GW Kent",
   "title": "Tri-clamp fittings guide: tube OD, flange OD and ID per size to 12 in; solid cap thickness",
   "url": "https://www.gwkent.com/triclamp-guide",
   "formats": [
    "web"
   ],
   "license": "publisher's guide; dimensions cited",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Rubber Fab",
   "title": "Tri-Clamp gasket dimensional chart: gasket ID, OD and bead diameter per size (2 in bead 2.22 in / 56.50 mm, 1.5 in 1.71 / 43.50, 3 in 3.29 / 83.50)",
   "url": "https://shop.andersonprocess.com/media/assets/product/documents/rubber-fab-tri-clamp-dimensions.pdf",
   "formats": [
    "PDF"
   ],
   "license": "maker chart; dimensions are facts",
   "license_verified": false,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "tri-clamp-brewing-sensor-lids",
  "tri-clamp-hose-barb-adapters",
  "esp32-devkitc"
 ],
 "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": "What sensor?",
   "a": "A 5 mm IR LED on one side and a 5 mm IR phototransistor on the other, pressed into the Ø5.1 holes."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "optical-bubble-counter-1-4in-barbs",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/tri-clamp-bubble-counters/optical-bubble-counter-1-4in-barbs.step",
   "stl": "https://xemstudio.com/files/hardware/tri-clamp-bubble-counters/optical-bubble-counter-1-4in-barbs.stl",
   "note": "optical bubble counter: Ø24 × 70 chamber, ¼ in barbs in and out, inlet tube to 10 above the floor, two Ø5.1 LED holes facing across the bubble path 22 up"
  }
 ],
 "markdown": "https://xemstudio.com/objects/tri-clamp-bubble-counters/index.md"
}