New Books and Magazines This Month
This month's new book is Building the Maltese Falcon, by Jim Shelley, published in England by Camden Live Steam, ISBN 0-9536523-8-6, 2003. It is A4 size (8-1/4 x 11-3/4), spiral bound with 32 pages of glossy photographs and text, followed by 11 A3 size fold-out pages of drawings (11-3/4 x 16-1/2"). My copy, and presumably all other first edition copies, came with a replacement for one of the drawing sheets, printed on the reverse side with a publishers apology, and a list of errata. Would have been nice if the replacement had been punched for insertion, but you can get there with scissors and glue.
The engine detailed in the book is an air-cooled, four cylinder, side-valve four-stroke. As you can see from the cover picture, having no over-head valve gear to accomodate makes for a very compact "boxer" configuration. It is fitted with a pull-starter, and has a magneto turning at twice crankshaft speed for the ignition. Lubrication is pressure fed from the 400cc sump. This is a big engine (seems like this is the month for "big"). The bore and stroke are both 44mm, giving a total displacement of 240cc. The design came about from the author's desire for a power-plant that would fly his 15 foot span scale Taylorcraft with a scale-like prop and sound. Development consumed six years and from the evidence of the photographs, he has been successful.
No complex castings are required to complete the engine. In fact it could be built entirely from bar-stock and plate; the builder having to buy only the bearings, fastners, and the Minimag magneto. The supplier of the latter may also be able to supply a casting for the crankshaft—which would save *lots* of chips—and you have the option of using Honda pistons, rings and valves (Honda motor cycle parts; this thing is bigger than a lot of bikes on the road today). The drawings show the piston details for those who prefer to make their own, but omit the details of the two compression and single oil scraper rings.
The book is not a step by step "how-to", and does not claim to be. Anyone tackling an engine of this size (a very lethal size, I might add), can reasonably be expected to require little to no assistance. The text works through the major engine components and subassemblies, covering only the less obvious aspects of the design and assembly. The black and white photograps that accompany this section are clear and will answer most questions with a minimum of head scratching, although they represent a number of stages in the evolution of the design.
The plans are "reasonable". They are hand drafted and lettered (not CAD), and the title box indicates that they were checked by the designer. My reading showed some errors—as well as the lack of ring data already mentioned. The lateral cross section shows the "old" combustion chamber shape. This is substantially different from the shape seen in the 3D model cross section on the rear cover. The head drawing itself does not supply the full height dimension for the head; only the fin depth. A note in the page discussing the head evolution suggests 1.25", but omissions of this type clearly indicate that this is an engine for the experienced constructor.
I find it hard to come up with an opinion either for, or against someone else buying this book. On the one hand, I can never really see myself building one. On the other, the way Shelley went about implementing his side-valve cylinders would scale down, and has given me an idea that may enable me to build a Westbury Kinglet without the aid of castings, so it may have been worth the modest cost for that alone. But if you are one of the Giant R/C Scale Brigade, the engine may be just the ticket. I've looked and looked, but can find no explaination for the name—if there's a Bogy connection in there, it's way too subtle for me!
Engine Of The Month: Sugden Special
The Sugden Special high-performance diesel (these things are relative) will probably need no introduction to English, Kiwi, and Ozzie readers, but may be new to those in the USA. The serialized series describing its construction began in the Aeromodeller, issue 227 of December 1954 (with the lovely C Rupert Moore "Mossie" painting on the cover, and plans for a C/L scale Mosquito powered by two ED Racers inside).
Although it is now over 50 years old, the Sugden Special would still make a fine project choice for any model engineer with a little IC experience under the belt. In fact, it was a Google search on the Sudgen that led to the X-List Plans mentioned above (plan U588). The engine has been on my must-build-someday list since just about forever. I'm no closer, but that's no reason you shouldn't be. Click the picture above to read all about the Sugden, and I do mean ALL.
And be warned if you want to repeat the web search: a popular BBC TV comedy series called Are you Being Served? had one Molly Sugden as a cast member (no relation as far as I know). She also did some TV "specials", so expect lots of false hits unless you add extra filtering terms to the search 
.
Tech Tip of the Month: Crankshafts Again
Remarkable how some things that should be memorable somehow manage not to be. While preparing the Sugden Special review for this issue, the way that Dave Sugden had tackled the machining of the crankpin absolutely leapt off the page at me. Now I must have read this a number of times previously, but somehow this very unusual technique never managed to have much of an impact. But it looked perfectly practical, especially for small shafts, so the How To Make Crankshafts page has got an update based on my tests of Dave Sugden's pin forming method.
The MEN-ONLY CD Collection
Editorial
