The Ed Baby
Updated: July 2008
In 2000, Bob Washburn, editor of SIC shook up his readers by publishing a blank page with an ominous note in the middle saying that he had insufficient material to fill the issue and that contributions were urgently required. This was more shock treatment than reality, but it prodded me into action, proposing to Roger Schroeder that we make a twice size version of the ED Baby. Roger's reply was, "why not make it full size?", so we did.
In due course we produced fully detailed CAD plans, crankcase casting sets, three running prototypes, and the most painstakingly proof-read and minutely complete set of machining instructions ever written, accompanied with high quality, camera-ready black and white phototograps. This article would, we were convinced, raise the bar at SIC for all time (we're humble, too). In other wrods, we'd become our own worst enemies since such quality takes time, lots of time. By time we "submitted" to SIC, RAW had a stack of new material that pushed our masterpiece so far down the publishing queue that SIC had closed up shop before we ever got anywhere near the top!
Naturally, we were disappointed and Roger vowed that by hook or by crook, this article would get published. So he lobbied Tim Dannels to have it appear in the Engine Collectors' Journal. Tim came to the rescue and the article was serialized over seven issues of ECJ starting in Volume 25. I made a pattern for the crankcase and sent it off to Roger, who changed it around until it could actually be rammed up and cast. Roger made one prototype and I made two. All were successful, though they re-taught us things about small diesels. Sand cast cases, including full drawings, are available from Roger through his Classic Model Airplane Engine Construction Kits series.
Historical background and details appear on the ED Baby page. The links below will take you to an expanded version of the construction series. A word of caution: for just about all the reasons enumerated in the pages on the Engines Designed for Beginners page, the Baby is totally unsuitable for a raw beginner. But it can and has been successfully tackled by engine builders with something like the ML Midge under their belt, or Model Engineers turning to IC from clocks or live steam who are accustomed to working with precision and tricky, delicate workholding. All that said, the construction series goes into some detail on process and things to watch out for—which the more experienced are free to ignore, or laugh at.
Introduction and Venturi Insert
Crankcase and Major Components
Cylinder and Piston Assemblies
Crankshaft and Sundaries
Final Assembly and Operation