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Strut drive (submerged prop)

Name: Strut drive (submerged prop) dimension sheet
Creator: Xem Studio
License: https://creativecommons.org/licenses/by/4.0/

How is a strut drive set up on an RC boat? · Standard part · basis: Design rules and figures from the cited sources; example geometry by Xem Studio

Also called: strut drive, rc boat strut, strut angle, prop strut, strut height rc boat, strut offset, rc boat drive setup, propshaft angle, strut shim

Exact dimensions. True size, with no printing tolerance added.

sizes: 5 in table

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.

Strut drive size chart

parameter	value or range	source
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)

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Model Gas Boats	Some tips on setting up a hydroplane hull	web	Publisher's page; dimensions are facts
Model Gas Boats forum	Stinger drive versus strut support set up	web	Publisher's page; dimensions are facts
Model Gas Boats forum	Need help setting up a mono for the first time	web	Publisher's page; dimensions are facts
SV Design	Pro Boat Stealthwake upgrades info (Feb 2022)	web	Publisher's page; dimensions are facts

Free files

★ Free files 1 parts. Xem Studio design: free to use, print and sell things from; not to be republished as files. Xem Studio Design License. index.json

strut-drive-propeller

1.73×2.43 in propeller, 2 blades: each section set at the geometric pitch angle atan(P / 2πr); chord and section illustrative

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Plain text: sheet.txt · JSON: /api/geometry?object=strut-drive