Model Engine News: May 2003

 

Editorial

April passed with, wonder of wonders, more activity in the shop and news of two extremely large model engine collections destined to come "on the market" as it were. One, sadly, through the passing of the owner, and the other through an act of philantrophy that deserves recognition and applause. You may also notice that I'm getting better at having the editorial page appear at the start of the month--amazing what you can do by writing it during the month rather than waiting until it's all over (duh and doh).

Vale: Miguel de Racougne

Sad news from the UK via Ken Croft and Eric Offen tells of the passing of engine collector and model enthusiast Miguel de Racougne, who lost his battle with cancer. Miguel was a comparatively young 63. In the later years of his life, his declared objective was to have the largest and best engine collection in the world. He was a great man, and a loss to the world of small engines. David Owen, with whom he stayed for a short time while visiting Wollongong five years ago, recalls him as a very urbane, aristocratic man, most pleasant at all times. I don't know if Miguel achieved his ambition, nor how you'd verify that satus either, but it obviously gave him pleasure in otherwise difficult times, so as usual, it's the journey, not the arrival that counts.

The Legacy of Ivor F

The name of Ivor F (no period) will need no explanation to an Australian modeller, but the broader readership may be a bit mystified. Today, most countries have a national body that "administers" aeromodelling activities, providing third party insurance, FAI affiliation, etc. In Australia, it's the Model Aeronautical Association of Australia (MAAA) which came into being in 1948. Prior to this, individual states did their own thing, issuing their own membership numbers. In 1952, members of MAAA affiliated bodies were allocated unified, national "VH" numbers (in Oz, full-size aircraft registrations are prefixed with "VH", just like the "N" numbers in the USA and "G" letters in England), and one Ivor Francis Stowe was granted VH-1 in recognition of the attention his activities had gained.

Following service in WW II, Ivor taught at a number of Sydney area schools, always encouraging and assisting youngsters to take up aeromodelling, frequently using materials and supplies from his own pocket. His life-long pedagogic leanings, plus a spirit of rugged individualism that we think is uniquely Australian (but isn't ), eventualy led him to take a stance on spelling--a very firm stance, and to show total commitment to his views, he changes his name to Ivor F (no period, no nothing). Unfortunately--or fortunately, depending on your point of view--his scheme did not gain overwhelming acceptance. Still, Ivor wrote a series of articles for the ozzie mag Airbourne on Gordon Burford's engines using his rules which seem to include some injunction against the use of adjacent vowels, so head for example, becomes hed, and I'll leve you, der reder, to form yor own opinin!

Well anyway, I received emails from a couple of Sydney residents who'd seen a newspaper article that told of Ivor's intention to sell off his entire model engine and magazine/book collection and donate all the proceeds to charity, or local schools depending on which newspaper you read. As this collection was reported at some 1800 (that's one thousand, eight hundred) engines, we are talking a significant sum, especially if it happens at eBay prices (saw a clapped "bones" Taipan 1.5 go for over A$60 this month--total lunacy!) Ivor is not only an Australian icon, but also a partiot, so a very large part of his collection is Taipans and other Gordon Burford designs, plus I'd expect a number of the engines Ivor himself manufactured over the years (the Sesqui, Elfin 149 ABC, the "Doonside Mills"...).

Now call me old fashioned, but I tend not to trust the press. So I asked local (Brisbane, Oz) collector Ray Strinati who is a close friend of Ivor's if he could confirm the story. Ray reports that the press *nearly* got it right. Ivor is selling a part of his collection (the duplicates) and the proceeds will go to his school. How and when this will all take place, I've no idea. Neither do I have contact details for Ivor. All I can say, is Watch This Space.

New Books and Magazines this month

Issue #74, dated March 2003 of Model Engine World arrived just before Easter. This is the fourth issued printed since Andrew Nahum took over and completes his first volume/year(?) As all subscriptions are geared to the year/volume, renewals are now due and overseas subscribers will be pleased to know that distribution arrangements will change from the next issue (see next item). Content wise, the magazine seems to have settled into a format with some historical articles on English model engines and their manufacturers, a "small engine" piece--as in it's small, but it's no model--this time on the de Dion Bouton four stroke tricycle engine. This is one that would make a fine subject for a scale model. A quarter scale version would come in at about 0.25 cuin. There's another metallurgy article, this time on "growing" cast-iron (a trick I've used to retrieve pistons, having gotten carried away with the honing--see the Original Taplin Twin). And finally a page of advertisements and a couple of pieces from past-editor John Goodall who at least provides nice, clear photographs. I wish Andrew well as he moves into his second year/volume of MEW.

Next, the other MEW, "Model Engineers Workshop", issue #88 for Feb/Mar 2003. This issue is notable to engine builders as it contains an article by Brian Perkins in which he describes his adventures cutting all the gears for the Bristol Aquilla and Hydra sleeve valve engines (notice how things seem to crop up in threes?) Brian's article is especially noteworthy as he believes he has uncovered an error in the formulae given for bevel gears in Ivan Law's book on gears and gearcutting. This is an excellent book in the Nexus Workshop Practive Series available in the UK from Nexus and Tee, or Wiseowl in the USA. It takes a very practical approach, especially geared to model builders (sorry 'bout that) with enough theory to cover what needs to be covered, while remaining more accessable than the in-depth coverage given in Machinary's Handbook and other professional texts.

Anyway, Brian has spotted two errors. The first is in the formula for the small end diameter of the bevel circle which is printed as:

	dia = pcd + (1/dp * sin cone_angle * 2)

The text uses a 45 degree gear as the example which is unfortunate as Sin(45) == Cos(45), and this is where the error lies: Brian asserts that it should be the Cosine of the cone angle rather than the Sin, and that this error is repeated in the formula for number of teeth to use when selecting the involute cutter required (which will not be the same as for a straight cut gear). Verifying this from the formulae given in Machinery's Handbook (p 1973 of the 25th edition) is not straightforward, so is left as an exercise to the student .

New Distribution Arrangement for Model Engine World

While living in the US during the late 90's, I had some dealings with a Califirnia company called Wise Owl Publications. The gals I spoke with were very friendly and helpfull, making dealing with Nexus UK much easier than trying to do it direct. Well, as reported by the editor in Model Engine World #74, starting from issue #75, Wise Owl will be handling "rest of world" distribution (England can still go direct to MEW). To summarize the info provided in the current issue:

Great Britian
	Send cheques for UKP17.00 to:
	Model Engine World
	74 New Street
	Woodbridge
	Suffolk IP12 1DX

Rest of World
	Europe: US$28.00
	USA, Canada, Mexico: US$25.00
	Australia, New Zealand and elsewhere: US$30
	Payment via credit card or US check (sic) .
	Web Site http://www.wiseowlmagazines.com
	email" info@wiseowlmagazines.com"

...and I should not have to add ...but will, that I've no connection with Wise Owl nor MEW--I pay for my sub like everyone else.

Sparey's Sleeve Engine

Remember last month I mentioned a reader query regarding model sleeve valve engines? Well by chance, a reference to a 1944 Aeromodeller article got rubbed in my nose late last month and I've now had time to chase it up a little. 1944 was a rather austere time for the British Isles. England had declared war on Germany on Sept 3, 1939 and although the tide had turned by this time, shortages and sacrifice were the name of the game for the public. Aeromodelling in particular had taken a blow with engine powered models banned for the duration and materials in very short supply (balsa having been declared a "strategic material" for use as ships life-preservers and rubber, well, you can imagine). Through all this, Aeromodeller somehow always managed to find the paper and kept publishing on a monthly schedule, even if many of the articles were of a highly theoretical nature.

Lawerence Sparey was a regular contributor, with a series titled My Engine appearing in the April 1943, and January, February and May issues of 1944. But it is his June article titled A Horizontal Single Cylinder Engine that prompts all this verbiage. In his article, Sparey concludes that all model aero engines are variations on the motor-cycle theme and sets out to design "...a serious attempt to evolve an engine which will suffer none of the inconveniences so far endured, and which will, besides, have additional features inherent in the design, especially adapted for model aircraft use."

The article goes on to describe what he viewed as shortcomings in existing engines and how he proposed to overcome them. Accompanying it was a single illustration, reproduced here, that shows what at first appears to be a twin cylinder, horizontally opposed engine configuration. Closer examination shows that one cylinder is a "fake", serving as a fuel tank for the other cylinder. The horizontal arrangement seems to have arisen as a compromise between advocates of inverted engines (Dr. Forster) and the upright (Col. Bowden). Both had attacked the design Sparey had proposed in his earlier article with all the usual vehemence and vitriol that only the British seem able to muster when composing "letters to the editor". As both were well respected experts, Sparey tried to strike a compromise by poking the cylinder out the side, and introducing an opposed mate to "...assume some symmetrical sembalance."

Now, ignoring all the problems this arrangement causes with fuel feed during an unbalanced turn, we can focus on the unique feature of the design, being the form of inlet valve chosen. Sparey termed this a "sleeve valve", while he noted that it was in fact derived from the rotary disk valve which he favoured. Certainly it bears no relation to what is termed a sleeve valve in full size aircraft engines where the cylinder sleeve is coerced into motion to uncover inlet and exhaust ports (many examples of which, manafactured by Bristol, were making nightly visits to Germany at this time). If anything, Sparey's inlet valve more resembles a front rotary valve, migrated into the crankcase cavity, his intent being to get the venturi safely away from the prop.

Although he labelled the engine "Patent Pending" in the article, no evidence exists to show whether a patent was ever granted (frequently, the "Pat. Pend." approbation was more of a "Keep Off The Grass" sign to imitators). However, one post-war engine similar in layout did briefly appear. It was called the Lionheart and was offered as diesel or glow ignition, with the glow plug version having the unusual "patented" ability to alter the compression! As with Sparey's design, the second cylinder served as fuel tank, feeding a conventional side-port cylinder rather than Sparey's "sleeve" valve arrangement and I doubt Sparey contributed in any way--although I've no evidence one way or the other.

For a single cylinder engine, the difficulty of manufacture and friction increase inherent to this inlet valve make no practical sense. But for an opposed two stroke twin, this arrangement has genuine appeal. One of the problems with such an engine is trying to get even mixture distribution to both cylinders. If we were to use the center segment of a two-throw crankshaft to drive a Sparey-type rotary "sleeve" valve, it could sit midway between the (staggered) cylinders and provided enough of the center web can be removed to permit relatively unobstructed fore-aft gas flow, we're in good shape with only a suitable conrod big-end arrangement to facilitate assembly being required. But wait! I'm probably too late with this idea. A close look at the FMO boxer twin diesel shows that this is probably exactly what the designer has used. Still, nice idea...

More Sparey Mania

One could be excused for thinking I've become a bit obsessed with Lawerence H Sparey And All His Works. Not so! But I'll have to admit that I started work building his 1946 5cc "Aeromodeller" diesel this month--it's just a diversion folks, and I'll get back to finishing the Mortons Real Soon Now, trust me! Still, all that replication work on the Mortons has rubbed off and it looks like I now have difficulty just making one of something, so there will be two Sparey 5's. As usual, I've taken a few blurred construction photos and made incomprehensible but lyrical observations. Details can be reached through the Sparey Story page, or you can go direct by following this link...

Battiwallah Revisited

Last month, we saw a picture of Vincent Chai's Battiwallah 1.5cc diesel made with a die cast case (per the original 1947 Model Engineer construction article). Here is a photo of the as-cast crankcase components from Vincent's home foundary. The picture does not really do them justice and even though Vincent says every set he's poured comes out different, they look just fine to me (and to the eagle-eye readers who spot a slight blemish on the end of the projection on the aft of the main case casting, this is the chucking spub which will be parted off after the case interior is machined--although on Vincent's engine, it was creatively turned into an integral fuel tank).

More Engines in the Finder

This month I've added a whole bunch of engines to the Engine Finder that have been sent in from all over (thanks to Bert Striegler, Charlie Stone, David Owen and anyone else I've forgotten). Go looking for new Foxes, Merco, a Veco, a rare Mamiya 60 Ignition, the Westbury Kestrel, Ten-Sixty-Six Products' Conqueror and Falcon, a Taipan Series 66, and an unusual Dyno clone from Sweeden called a "Vasteras".

More Engines in the Gallery

I received some photos from two readers during the month that have been added to the Engine Gallery Page. These are four concourse quality works from Les Stone: A Nova I (from Ken Croft castings, pre his Motor Boys induction), a Rogers and Geary Wasp, and a pair of outstanding multy cylinder engines; the two cylinder Furgerson Falcon and the four cylinder Condor. These are big brutes designed in 1936 with blind cylinder bores (all you who've honed a blind bore will certainly appreciate Les's work!) The other addition is an unusual freelance glowplug design by Charlie Mynhier that features a flywheel and belt driven cooling fan. While I liked the concept, I was a bit sceptical as to its effectivness until Bert Striegler pointed out that it is geared up and probably produces more than enough of a blast to stir up any loose papers.

More Mia in the Culpa

And finally, it's not often I make factual mistakes, rather it's frequently! Last month's boo-boo was in crediting the design of the AMCO 3.5 BB to Den Allen, when as everyone knows, it was EC (Ted) Martin; as was the "MAN 19" diesel I also credited to Dennis. So a big sorry to all those who have now to un-learn this error, and a big thanks to Neville Palmer for bring it to my attention. I'll try to do better... honest...