This is the second shot at a steam-powered mechanical spider with Crabfu, his patience is greatly appreciated. The design goal was to keep it as simple as possible and use readily available components. The flat pieces are all cut in 2D with the exception of the crank arm, which has a countersink for a bolt. All of the material is available online, including the steam engine.
The steam spider II is still a work in progress. It is planned to be an all-metal machine. All of the custom pieces, including the gears, were cut on a bench-top CNC mill. Here are a few pictures at various stages.
This video clip shows an unfinished spider during a test run. It moves slowly like most machines that are powered by a steam engine.
A final assembly drawing can be seen with Edrawings® Viewer. This free viewer is a powerful tool. It will allow you to view the steamspiderii.easm file (and other formats) in 3D, rotate, zoom, and look at the pieces individually.
Click this link to download the Steam Spider II assembly drawing (0.67 Mb) steamspiderii.easm
Click this link to download Edrawings® Viewer (8 Mb) from the Solidworks® website.
There are a few details and modifications needed to complete the drawings and several components left to fabricate. Updates will be posted as the project progresses.
Future versions have been considered that would use a tractor-fed punch card like a player piano with several tracks for programming simple functions like turning, blowing the whistle, or launching a catapult based on where holes were punched in the tape.
It is easy to dismiss steam engines because they lack the efficiency and power of internal combustion or electric motors but there is a fascination for some that can appreciate their simple charm.