History

This two-cylinder 7" bore x 7" stroke "Launch Engine" is typical of those used in the late 19th to early 20th Century in small boats and launches in the 35 foot to 50 foot range. They were very robust, dependable and easy to maintain, and usually powered from a "Scotch" style horizontal, or a traditional vertical fire-tube boiler, burning wood or coal. The valve chests are unusual in that they are inboard, rather than the common outboard location. This resulted in a compact design, but was likely difficult to adjust the valve timing. This is of the "simple" concept of equal sized cylinders, known as a "single expansion" design, rather than the more steam efficient "compound" concept.

The Model

This is a museum quality reconstruction, reverse-engineered from drawings in the book Machine Drawing and Design, self-published by the British author William Ripper in 1889, as a textbook for young Engineering and Drafting students. Every part is accurately modeled and fully functional for animation, with the exception of the steam throttle valve. It is likely that this engine has never been made, but my SolidWorks™ CAD model proves that all parts fit perfectly, and the design reflects correct steam engineering practice.

This high resolution 1,257,328 poly CAD model allows for extreme close-ups and rendering. It is ideally suited for hero and foreground shots and CG’s. All parts were color-mapped in SolidWorks™, and migrate to the .obj format.

The SolidWorks™ model was converted to .obj (Combined based on Structure) using SimLab Composer. Renderings were created in KeyShot2 from Luxion.

I also offer this model in the Parasolid format for those who may wish to actually build this fine Steam Launch Engine. However, I cannot warrant the usability of the CAD model for actual construction.