Model Engine News: February 2005


Special Features:

   The First "Diesel"
   Kiwi Progress
   Correction: GHT and the Quorn
   Feeney Kits
   Early ETA
   Zimmerman Cirrus, Cirrii?

Regular Features:

   Editorial
   New Books and Magazines This Month
   Engine Of The Month: Channel Island Special
   Tech Tip (1): Crankcase Pattern Making
   Tech Tip (2): Steel in Steel
   Tech Tip (3): The Putting-on Tool
   Standard Stuff

All material on this web site is Copyright (c) of Ronald A Chernich 1999-2005, and all rights are reserved, world-wide. No text or images my be reproduced in any form without explicit permission of the copyright holder.
I truly regret having to add this, but after seeing my own words appearing uncredited in eBay auction descriptions, it's time to get petty. If you want to use any material, just ask. Non-profit usage will almost certainly be permitted and blessed, but if you plan to get rich on my work, I want a piece of the action!


 

Editorial

It sure has been a hot month here (and wet too—an ugly combination). A radio news item I just heard said Mount Everest is suspected to have got shorter due to Global Warming, so a team is being sent to re-survey it. And that (the heat, not the shrinking mountain) is my excuse for Things Not Done. Shop activity was confined to making the pattern for the Mills 1.3 crankcase, cutting yet more skew gears for Feeneys, and fixing a small mistake made over five years ago—as you'll read in the news items below.

I should mention that the launch date for Model Engine Builder is approaching fast, so if you've not subscribed, go to the MEB web site and do it now (I'll wait 'till you come back). The first issue will be a beaut. I've seen preliminary cover art and can say that Mike's work raises the bar significantly for small, niche market, special interest publications. Mike will be at NAMES, so if you plan on attending, drop by and say hi.

And I'm not going to be so foolish as to mention the left-hand navigation panel—it's far too embarrassing. For some time, my team and I have been deep into the field of inverted index compression and searching. This may find some expression in the Site Search Facility to speed it up and add word 'stemming' (an option to find references to compressed, and compress when you enter a search term of compression). It's all good clean fun that can be done in air-conditioned comfort while I wait for the shop to cool.

Now, on to business. If this lead page looks short-ish, don't despair—it links to four quite long new pages. We have three Tech Tips this month, some in-depth research into a relatively rare and historic engine, plus other good stuff. Hope you enjoy them...

The First "Diesel"

Let's buy an argument. Many would name the Swiss Klemenz-Schnek Dyno as the first commercially available compression ignition engine [1][2] (frequent readers of these pages will know that "CI" is the correct name for engines we more commonly term the small-dee "diesel"). However, Fisher [3] gives this distinction to another Swiss design, namely the "Etha". As evidence he shows an engine asserted to have been purchased by the Spanish Air Attaché in Geneva in 1941. Manufacture of the Dyno is accepted as commencing in 1946, so if true, Fisher is correct regarding which was first.

Today, Ethas are as scarce as rocking-horse droppings. Naturally, there was one in Miguel deRancougne's collection (Lot 249, shown above), and Les Stone was fortunate enough to borrow it, disassemble it, and make some sketches so that he could build the replica seen here. Les sent several pictures of his latest creation, and these have been added to the Les Stone Tribute Page of the Engine Builders' Gallery. Les' sketch will certainly get the Motor Boys CAD treatment Real Soon Now.

[1]  Bowden, CE: Diesel Model Engines, 1947 (reprinted by TEE Publishing 1993), England, p48.
[2]  Laidlaw-Dickson, DJ: Model Diesel Engines, Horace Marshall & Son Ltd, England, 1947, p8.
[3]  Fisher, OFW: Collectors' Guide to Model Aero Engines, MAP Publications, England, 1977, p27.

Kiwi Progress

Nick Jones has made some more progress with his Westbury Kiwi. His first plan was to use CNC to make a wax head, then cast it using the lost-wax technique. The fall-back plan was to CNC it from aluminum and that's what the new set of photographs on the Kiwi Construction page show. I've heard some say that CNC is not "real" model engineering. I could not disagree more! To me, model engineering is the joy of developing skills and techniques to build models in metal. CNC is just another technique—and one with a steep learning curve. Nick says there are 23,000 lines of instructions in that head, taking over 6 hours to rough it out a few thou at a time with a very delicate cutter. And he made two of them before he was satisfied (we won't embarrass Nick mentioning the layout error in the first that led to the second ). His program even reproduces the draft angles on the fins, and the finished product shows considerable hand re-working to make his head resemble the sand casting of years gone by. Great job Nick, and if I had the space, I'd have a CNC mill too.

New Books and Magazines This Month

Two new, long awaited model engine related publications arrived in The Library this past month: Volume 29 of The Engine Collectors Journal, and issue #77 of the "new" Model Engine World. I'll deal with the last one first.

If you read my review of MEWs #75 and 76 back in the November Editorial page, you may recall that I was whelmed; not under-, and most certainly not over- ... just simply 'whelmed'. So I'm now happy to say that although the production values employed by the 'new' series of MEW have dropped, the rise in content value more than compensates—to me, at any rate. This lowering of production quality is not catastrophic. Issue #77 is on a par with issues produced by Goodall for the 'old' series of MEW: a simple single color separation for the cover, and buff paper throughout. In other words, the glossy paper and full color pages are gone, but the layout is clean, the printing good, and photographic presentation perfectly adequate. The cover art of this issue is unattributed, but unless I'm mistaken (quite possible), it looks like one of C Rupert Moore's early Aeromodeller cover paintings.

Speaking very subjectively, the content rates way up there with the best, but then perhaps the article on the horizontally opposed Morin Airspeed .50 by Giancarlo Mensa had something to do with it . This follows on from an earlier article on Morin's designs and casting kits that appeared in issue #76. Giancarlo has acquired an example of this rare French engine and his research shows two subtly different Airspeed 50 variants. Mention is also made of Morin's booklet on engine building. I have a photocopy of this booklet that shows a third variation of the Airspeed, as seen here. Giancarlo's article mentioned a variation in the number of cylinder fins. His drawings show 13 fins, while the engine itself has only 10. Prompted by this, I counted the fins on my drawing: 11. Count again: 12! Count a third time: 11!! Oh wait, the left cylinder has 11; the right has 12. Brilliant. That will keep collectors guessing for years...

Returning to MEW #77, it follows the format established by prior issues in the 'new' series, containing a mixture of full size, model, and unusual designs. The full-size engine historical article for issue #77 is by Sandy Skinner on David Pobjoy and his designs. As well as containing more detail about Pobjoy than I've seen anywhere else (including Alec Lumsden's excellent and expensive British Piston Aero-Engines and their Aircraft), it concludes with a table giving engine specifications for all his designs that is believed to be the first such treatment of these little-known, but delightful powerplants. Other articles in #77 detail Yet Another Cycle Motor (with reproduced drawings), and a very unusual rotary design (in the Wankel/Saritch use of the term). A good issue that makes me look forward to #78—which will be the last in the current 'subscription' for this quarterly publication.

Next we have Volume 29 of The Engine Collectors Journal. ECJ volumes comprise six issues. These appear as editor Tim Dannels finds sufficient material to fill an issue—there is no rigid publication schedule, nor relationship between a volume and the calendar. Subscribers get the six issues as they are available, but Tim provides another option which is to wait however long it takes, then get the issues bound as a nice, thick, soft-cover "volume"—which is the way I like to take my ECJs. So volume #29 comprises issues 163 through 168, covering February to December, 2004.

As usual, it contains a great spread of content: two engine construction series; an [ahem] *excellent* though hauntingly familiar restoration article on making conrods; in-depth coverage of makes and models, unusual and one-offs, etc, etc. An old feature making a reappearance in this volume is a series of bios on noted engine collectors and authorities such as Bert Streigler, who should need no introduction to readers of this site. Naturally, Bert's feature includes a reproduction of his fameous Ebenezer free-flight design. The same issue contains full coverage of the Zeiss Jena engines from East Germany by noted European authority, Holgar Menrad. I'm sure there will be something for everybody in this volume, which is a bargain at only US$17.50. Contact Tim at ecj@chaffey.net for details.

Engine Of The Month: Channel Island Special

We very nearly didn't have an Engine Of The Month this month, but a late email from a long-time reader of these pages came to the rescue! The engine is appropriate too, as it was designed by Edgar T Westbury—whose work we've been following for the past few months. The manufacturer named it the "Channel Island Special" (for reasons which will become apparent), but although it was a fine running, powerful, well-made engine, it was not a commercial sucess. Read all about it on the Channel Island Special page, and wouldn't you believe it? My first review after cataloging all those 1300 model engine reviews and the index was no help whatsoever!

Correction: GHT and the Quorn

Wow. Is my face ever red. The first HTML page I put together for web posting was my little 1996 adventure: A Rank Beginner Builds a Quorn. Last month I received an email from a fellow academic and self-confessed, would-be Quorn builder pointing out—quite correctly—that a quote in the article which I had attributed to George H Thomas in his posthumous Model Engineers Workshop Manual, was in fact and quite obviously made by the book's editor, William A Bennet. All fixed now; so sorry Will, sorry GHT (where ever you are), and no wonder my scrap bin is still full to overflowing (read the Quorn Adventure intro to figure that one out ).

Tech Tip (1): Crankcase Pattern Making

I am absolutely NOT going to claim any kind of superior knowledge at the art of making patterns for sand casting. But I can pass on a couple of tips that may encourage you to have a go and so become your own resident expert. The photo here is for the Mills 1.3 Mk I replica case which will appear in Roger Schroeder's Classic Engine line in the near future. As Roger tells me that the pattern "pulls clean" from the sand, I will pass on, with a degree of trepidation and the usual amateur caveats, how the pattern was made. Click the picture, or the link for a very short treatise on pattern making, which has been added to the Model Engine Construction Techniques Section.

Tech Tip (2): Steel in Steel

Last month I mentioned the steel piston in a steel liner experiment used successfully on the Peperell and Mills P75 repros. Since then, I've had some conversations with Peter Burford on this topic. Peter, if you recall, is the maker of the exceptional PB .33 diesel which uses a hardened steel piston running in a hardened steel liner. It was the feel the compression this engine has, with no taper and no corresponding 'pinch' at TDC that prompted my experiment. Peter's observations on the subject are quite enlightening. Rather than print them here and potentially loose the information, I've included them in a new entry in the Techniques Section, along with comments on the other common Cylinder and Piston material choices available to the amateur engine builder. Thanks Peter for being the spark that initiated this hopefully useful page.

Feeney Kits

Followers of my Feeney Four-Stroke series of construction pages who feel they'd like to have a go too may be interested to know that Art DeKalb's Precision Service Co is preparing another run of kits. At the start of December, I made and mailed Art a batch of timing skew gears for the Feeney. Naturally, they never arrived. So I've now made another batch of ten which will go in two shipments to guard against the previous debacle. I'm sure this will ensure that the missing lot arrives just after the final batch of the last lot... grrrr. The photo shows two blanks for the 30 degree, left hand, 20 tooth gear being cut with a hob at once. It's not accurate to call this "hobbing", which infers that cutter and blank both rotate at an inter-connected rate, but the method, as described in Page Two of the Feeney Series works well enough for small runs and small gears. the shop-made "hob" has now cut more than 30 gears and shows no sign of needing sharpening.

Early ETA

Shown here is an early ETA 29, serial number 29484, in condition exactly as received and awaiting restoration. Although it's hard to see, the glow plug is centrally located in the top of the head. It is slanted towards the baffle which is why it appears offset in the underside view. The cylinder liner appears to have been cast into the case—don't know if this was standard for later engines or not. I'm mentioning this now, even though work will not start for a while because I will have to make rings for this engine. If you need rings for a Mk I Eta 29, let me know now as it's almost as easy to make ten as it is to make two. Mk I's only though as I can't be sure they would fit later pistons.

Zimmerman Cirrus, Cirrii?

The late Merritt Zimmerman designed replicas of the DeHavilland Cirrus I in 1/4 and 1/6th scale. He built several for sale (I've heard the figure 25 bandied about), and presented the plans to Robert Washburn to help kick-start SIC Magazine. The 1/4 scale version was built and documented by Ron Colonna. Eric Whittle did likewise with the 1/6 scale version and later reduced it to 1/9 scale. His plans and the construction feature for the latter appeared in English magazine, Engineering in Miniature. The cylinders, pistons, 'rods, and head of this engine formed the basis for Eric's Aero V8 that was serialized in the Model Engineer. This makes for a very satisfying symmetry, as the full-size Cirrus I, designed by Major FB Halford, began as the (metric) cylinders, pistons, 'rods, and heads of a Renault V8!

The 1/4 scale version is more sophisticated than the smaller model, having spark ignition, a wet sump, and pressure fed lubrication. Eric Offen has had one of these underway for some time and recently found himself on a roll of energy for the project which is starting to come together nicely. The photos below show Eric's engine in early January. I especially like his timing adjustment innovation. Note the offset hole pattern he's used to secure the large timing gear to the carrier on the cam shaft. This allows very small adjustments to be made to the timing, while the gears are rigidly keyed to their respective shafts. Eric machined the cams using the Cam Calc page of this web site, using 3 degree increments. He says this made it so easy, he is making multiple shafts with different cam profiles to see which produce the best results.

And to round off this item, a reference to an old friend: I just noticed that 5 Bears has posted construction pictures of the 1/6 scale Cirrus project. Lots of good pictures and words that describe not so much the build, as the re-build. The 1/6 scale model is a glow ignition version, so no oil pump is required. Just looking at this picture made me want to take my 1/6th scale Cirrus out from under the bench and fix the dog's breakfast I made of the timing gear carrier casting over five years ago. So I did, and that, as we'll see in the next item, resulted in a third Tech Tip for the month.

Tech Tip (3): The Putting-on Tool

There can't be an experienced model engineer reading this who has not unaccountably, accidentally, and surprisingly, turned some critical part disastrously undersize. It's at times like these (after the blue smoke before one's eyes clears), that one could really use a tool that puts metal on, rather than taking if off. While such a magical device does not exist, we can in certain circumstances, achieve the same end. Our last tip this month is aimed mostly at those just starting in model engineering, and gives advice to store away for when (not if) this happens to you. So have a look at The Putting On Tool in the Model Engine Construction Techniques Section.

 

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