{
 "version": "2026-10-20",
 "license": "Dimension sheets: CC BY 4.0. Standard and published-size files: CC BY 4.0. Xem Studio's own designs (files_license = Xem Studio Design License): free to use and sell things from, not to redistribute as files — https://xemstudio.com/license/. Other publishers' files: their own license, linked beside them.",
 "slug": "strut-drive",
 "name": "Strut drive (submerged prop)",
 "kind": "standard",
 "category": "Boat design",
 "group": "Hull types",
 "year": null,
 "question": "How is a strut drive set up on an RC boat?",
 "tags": [
  "vehicle design",
  "hull types",
  "rc design",
  "aerodynamics"
 ],
 "aliases": [
  "strut drive",
  "rc boat strut",
  "strut angle",
  "prop strut",
  "strut height rc boat",
  "strut offset",
  "rc boat drive setup",
  "propshaft angle",
  "strut shim"
 ],
 "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/strut-drive/",
 "sheet_txt": "https://xemstudio.com/objects/strut-drive/sheet.txt",
 "sheet": {
  "basis": "Design rules and figures from the cited sources; example geometry by Xem Studio",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "A strut holds the propeller shaft behind the transom; its angle and depth set how the prop lifts or pushes down the stern. Manufacturers usually recommend 0 deg; 0.030 in of shim under a 1.75 in strut adds 1 deg (Model Gas Boats).",
   "Racers keep the shaft centreline 3/8-1/2 in above the keel with the strut flat or slightly negative, and offset the drive to starboard to counter torque roll (Model Gas Boats forum).",
   "The file is a reference example built by Xem Studio from the numbers above (44 mm RC prop (SV Design).). Sizes the sources do not fix are illustrative; scale the example to your own vehicle."
  ],
  "table": {
   "columns": [
    "parameter",
    "value or range",
    "source"
   ],
   "rows": [
    [
     "Default strut angle",
     "0 deg",
     "Model Gas Boats"
    ],
    [
     "Shim per deg (1.75 in strut)",
     "0.030 in",
     "Model Gas Boats"
    ],
    [
     "Shaft height",
     "3/8-1/2 in above keel",
     "Model Gas Boats forum"
    ],
    [
     "Offset to starboard",
     "1/4-3/8 in (mono)",
     "Model Gas Boats forum"
    ],
    [
     "Stock RC shaft angle",
     "about -6 deg",
     "SV Design (Stealthwake)"
    ]
   ]
  }
 },
 "sheet_text": "Strut drive (submerged prop) — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/strut-drive/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)\nBasis: Design rules and figures from the cited sources; example geometry by Xem Studio\nCatalog version: 2026-10-20\n\nSizes: see table below\n- A strut holds the propeller shaft behind the transom; its angle and depth set how the prop lifts or pushes down the stern. Manufacturers usually recommend 0 deg; 0.030 in of shim under a 1.75 in strut adds 1 deg (Model Gas Boats).\n- Racers keep the shaft centreline 3/8-1/2 in above the keel with the strut flat or slightly negative, and offset the drive to starboard to counter torque roll (Model Gas Boats forum).\n- The file is a reference example built by Xem Studio from the numbers above (44 mm RC prop (SV Design).). Sizes the sources do not fix are illustrative; scale the example to your own vehicle.\n\nparameter  value or range  source\nDefault strut angle  0 deg  Model Gas Boats\nShim per deg (1.75 in strut)  0.030 in  Model Gas Boats\nShaft height  3/8-1/2 in above keel  Model Gas Boats forum\nOffset to starboard  1/4-3/8 in (mono)  Model Gas Boats forum\nStock RC shaft angle  about -6 deg  SV Design (Stealthwake)\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Model Gas Boats: Some tips on setting up a hydroplane hull — web — Publisher's page; dimensions are facts — https://modelgasboats.com/magazine/tech-articles-mainmenu-608/369-hydro-setup-tips\n- Model Gas Boats forum: Stinger drive versus strut support set up — web — Publisher's page; dimensions are facts — https://modelgasboats.com/forum/13-ask-the-editors-discuss-articles-general-boat-questions/16025-stinger-drive-versus-strut-support-set-up?start=0\n- Model Gas Boats forum: Need help setting up a mono for the first time — web — Publisher's page; dimensions are facts — https://www.modelgasboats.com/forum/13-ask-the-editors-discuss-articles-general-boat-questions/21138-need-help-setting-up-a-mono-for-the-first-time\n- SV Design: Pro Boat Stealthwake upgrades info (Feb 2022) — web — Publisher's page; dimensions are facts — https://myplace.frontier.com/~sv_design/Pro%20Boat%20Stealthwakes%20Upgrades%20Info%20SVC_Feb-2022.pdf\n\nFree files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/strut-drive/index.json\nAPI: https://xemstudio.com/api/geometry?object=strut-drive\n",
 "sources": [
  {
   "publisher": "Model Gas Boats",
   "title": "Some tips on setting up a hydroplane hull",
   "url": "https://modelgasboats.com/magazine/tech-articles-mainmenu-608/369-hydro-setup-tips",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Model Gas Boats forum",
   "title": "Stinger drive versus strut support set up",
   "url": "https://modelgasboats.com/forum/13-ask-the-editors-discuss-articles-general-boat-questions/16025-stinger-drive-versus-strut-support-set-up?start=0",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Model Gas Boats forum",
   "title": "Need help setting up a mono for the first time",
   "url": "https://www.modelgasboats.com/forum/13-ask-the-editors-discuss-articles-general-boat-questions/21138-need-help-setting-up-a-mono-for-the-first-time",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "SV Design",
   "title": "Pro Boat Stealthwake upgrades info (Feb 2022)",
   "url": "https://myplace.frontier.com/~sv_design/Pro%20Boat%20Stealthwakes%20Upgrades%20Info%20SVC_Feb-2022.pdf",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "deep-v-hull",
  "modified-v-hull",
  "flat-bottom-hull",
  "cathedral-tri-hull",
  "tunnel-hull-catamaran",
  "three-point-hydroplane"
 ],
 "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": "Why offset the strut?",
   "a": "To counter torque roll (Model Gas Boats forum)."
  }
 ],
 "files_license": {
  "name": "Xem Studio Design License",
  "holder": "Xem Studio",
  "url": "https://xemstudio.com/license/",
  "note": "Xem Studio's own design: free to use, print, modify and sell things made from it; not to be republished or redistributed as files."
 },
 "offers": [
  {
   "file": "strut-drive-propeller",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/strut-drive/strut-drive-propeller.step",
   "stl": "https://xemstudio.com/files/hardware/strut-drive/strut-drive-propeller.stl",
   "note": "1.73×2.43 in propeller, 2 blades: each section set at the geometric pitch angle atan(P / 2πr); chord and section illustrative"
  }
 ],
 "markdown": "https://xemstudio.com/objects/strut-drive/index.md"
}