Somehow, this edition has come together quite well (in my isolated, non-partisan opinion). One day I was panicking over what the devil to write about; the next I was panicking over how to find the time to put together all the material I wanted to present! It's almost spring here and I'm planning on some solid shop-time in the next few months—from which you may surmise that once again, I didn't manage to get any this month—again. However I have managed to complete the construction series for the Feeney (all bar the running segment), and do a write-up on an engine I've wanted to pull apart for some time. The little yellow sticky on the wall says there were 8,006 hits for August which is "stable". A little probing on the root of my web pages says there are now 409 different pages, comprising 375,675 words, with 4,452 photos (though I suspect not all of them are still findable).
All of which has absolutely nothing to do with the lead-in photo, which in turn has nothing to do with anything in this month's issue. It's a full-size "Hurribus", shot landing at Old Warden recently by Ken Croft. I suspect it's the Shuttleworth Collection aircraft. A beautiful, evocative picture that I just could not resist.
Allbon Bambi Oops
Over a year ago, I dug back into the mountain of magazines to put together a brief history of the Allbon Bambi. My findings described the grand Name the Engine competition that launched the engine with a full page splash in the Aeromodeller of November, 1953. I then waxed lyrical about the poor follow-up made by the Davies-Charlton marketing people. What can I say? Wrong again. I foolishly looked to the DC add on the inside front cover (the usual place for DC adds in the Aeromodeller) in December for the announcement. But the competition had been conducted by the Aeromodeller itself, asking readers to name the engine and the manufacturer, so the follow-up announcement was not placed by DC, but again by Aeromodeller with a full page announcement in the January 1954 issue. So, sorry readers, sorry Aermodeller, and sorry DC! The Allbon Bambi page has been corrected and updated and Ron is feeling very humble.
More Pepp 7/16
Only last month, I received a picture from Les Stone of the Pepperell replica he was working on, using the two-view outline drawing from the book, Those Fabulous Pepperells which was reviewed in the same issue. Les has now finished his replica and it bears his hallmark highly-polished finish. He reports it started easily, but was not immensely powerful. Since the reference Les was working from did not give the diameter of the fixed fuel jet, he'd started small and was working up gradually. Judging on the statistically suspicious sample of *one* that I've been able to examine and measure, the answer is 0.015" (#79 drill), or thereabouts, as the jets were pricked with a darning needle until they looked "about right"! Les found that a 0.010" jet gave very satisfactory performance, with the engine answering to the air-valve extremely well. The engine I borrowed from David Owen to measure has gone back. David has given it a run and is very pleased with the results, also reporting its quick and predictable response to the air-valve. I'm convinced.
Bee Confused, Bee Very Confused
Seems I managed to confuse a number of readers last month with the lead-in piece to the review of the ED Mark I "Bee". Re-reading it, I can understand and sympathize. First, the fact that there was a new ED Bee page was not obvious, and this was compounded by my use of a Series I engine for the subject heading, with a Series II engine photo to headline a story about the ED Mark I. A poor choice; very confusing. Two readers emailed me, gently suggesting I had it a bit wrong, then had to email again to say "oops", after they'd discovered the full page and read the Mark I Series I/Series II explanation. I believe it is the author's responsibility and duty to clearly express their thoughts, and in this I failed. Hopefully the lesson learnt will be remembered and future articles will be less confusing (with the possible exception of this explanation, having just re-read it). So, to set the record straight, the engine pictured here from Ken Croft's collection is an ED Mark I "Bee", Series I, with the standard metal tank. Click Here to read the history of the ED Mark I, Series I and II "Bees".
Ploughshares into swords? BMWs into Kiwis? Oh the Humanities, where will it all end? Following Phil Coleman's short history of the Westbury Kiwi that was added to the ETW pages last month, I received some photos of a Kiwi under construction from very talented UK builder, Nick Jones. Nick felt that the castings available to him did not meet his standards, so set about learning how to make patterns and pour molten BMWs into KIWI shaped cavities in Petrobond sand. Nick has kindly provided some pictures of his work and these have been added to the ETW Kiwi page.
The Watzit page does not get updated as often as I'd like, but we've got a good one for you this month. We (The Motor Boys) believe we know what it is, although only one of our number was able to make the ID, and even that's not 100%. So have a look and test your EQ (Engine Quotient). Our answer (which may change in the meantime) will be revealed next month.
Hold the presses! Just actual minutes before I was about to "publish" this issue, an unexpected email arrived from Eric Offen with photos showing the internals of the mysterious Scotch-Yoke flat four that only last month we thought may be an implementation of the Bourke Cycle design. I wasn't aware that Eric was the new, proud owner, or I'd have begged Eric to take a hacksaw to it earlier. But better late than never, and yes Eric did have to perform some severe (but non-terminal) surgery on the engine to strip it down a bit. And finally, just to demonstrate again that it never rains (especially downunder, these el Nino days!) when it can pour; look at what Eric is propping up the flat-four with to take the photo—a Pepperell case!! Somehow I don't think that is an accident . Anyway, the internals shots have been added to the Watzit page, so be sure to scroll down and take a look at the update on Yet Another Engine That Can't Possibly Run.
Jerry Howell's Engines
In case you haven't seen them before, the IC (and other) engines on Jerry Howell's web site are most definitely worth a look. The craftsmanship is superb and Jerry also sells plans and material kits for a number of his projects, plus coils and accessories for modern spark ignition. The engine pictured here is his 32cc 90 degree V-twin. Jerry notes that this is not a beginners project, but one that can be built by anyone with a few successful IC projects under their belt who is particular about their work. The plans for this engine, 41 CAD sheets, cost US$40. I have not sighted them, but less than a buck per page seems good value and I have not heard a bad word anywhere about Jerry.
New Books and Magazines This Month
Nothing new as such arrived this month, so I've delved into the archive and selected a couple ET Westbury titles that are still available as reprints from TEE Publishing in the UK (or Wise Owl in the USA).
The first is The Atom Minor Mark III, ISBN 0 905100 56 5. This a complete how-to book, including fully dimensioned drawings, originally published in 1933, describing the 6cc, two-stroke ignition variant of the Westbury's Atom series. It's a small volume of 50 pages that begins with Westbury's aims in developing the engine, written in quintessential ETW prose. Descriptions of the components follow with very detailed machining instructions. For instance, the section titled Exhaust Socket the describes how to drill a 3/8" hole occupies almost two pages (alright, I'm being unfair—the hole transitions from round to rectangular, is angled downwards with respect to the cylinder bore, and needs to register with the sleeve openings, so it's more than just any 'ol 'ole). Castings to accompany the book are available from Woking Precision, and possibly John Goodall (see the Suppliers Page).
The Atom was the first engine I embarked on a mere 9 years ago, though not the first engine I finished. In fact, I could argue that it's still not finished! My example looks nice, but has so many screw-ups that I've never bothered to try running it. All are fixable and I did learn a lot through close reading of the Atom book, and putting ETW's descriptions into practice. The Atom book concludes with a chapter on assembling the engine, but does not go as far as to cover setting up the ignition system and running the engine. My Atom was made with a 1/4"-32 thread for a glow-plug, not realizing back then that the compression ratio would be a bit too low for this form of ignition. And that provides the perfect segue into the next ETW title for this month which is devoted to the topic of spark ignition accessories.
Ignition Equipment by Edgar T Westbury was first published in 1948. It collects and condenses a long running pair of series by ETW that appeared in the Model Engineer. Part I, Principles and Practice, began in Volume 90, issue 2227 of January 13, 1944 and concluded in Volume 91, issue 2260 of August 31, 1944. Part II, Design and Construction started with Volume 91, issue 2268 of October 26, 1944, and concluded some time in Volume 94 (which I do not have). The book version combines selected material from the series. The 192 page book pictured here is a soft-cover reprint of the original, published by TEE in 1993, ISBN 1 85761 038 5. Like their Atom Minor booklet, it is still available. The question that probably occurs to you is how relevant is the book today, and how closely does it reprint his old ME series? Sadly, I'd have to say not very, and not that closely.
The second answer is probably explicable as the book needed to be able to stand by itself, whereas the ME series could take advantage of the readership's knowledge of ETW's Grand Oeuvre, and the context of the ME itself. The series therefore is much richer in text and illustrations. Over the long-running series, and to an extent in the book, ETW examines theory of coils, magnetos, contact breakers, and every (then) conceivable accessory, explaining and comparing full-size practice with what is required at model scales. His treatment is practical and informative, but omits such necessary things as coil-winder design and naturally draws on materials commonplace then, but not now. If you are planning on making some coils and want a how-to book, this is not it. If you are interested in magnetos, large, small, and miniature, you'd be better off buying the old MEs. They won't cost a lot (depending on where you have to freight them from), and you'd get a tremendous amount of extra stuff free, including several of ETW's engine construction projects.
Engine Of The Month: Mk 17
This month, we put the old Soviet-era Mk 17 1.5cc TBR RRV diesel under the microscope (well, magnifying head band at least). For no great reason, I've always been fond of this particular engine. And if you recall, just a couple of months back in the May 2004 issue, we led off with some photos courtesy of Ken Croft, showing a most attractive four-stroke glow conversion. So I though the time was way past due for an in-depth look at this delightful little design. Having previously seen pictures of the disassembled engine in Aeromodeller, I though I was prepared for what lies beneath, but still found surprises waiting. Read all about it on the Mk 17 page, also reachable (naturally) through the Engine Finder.
Tech Tip of the Month: Think!
Computer industry folklore says a sign bearing the word "Think" adorned the wall at IBM, placed there by founder TJ Watson. It's good advice. This month's tip, a corollary to "Think", is the old admonition to "Measure Twice, Cut Once". It's backed up by two practical illustrations related in the Feeney Construction Log: page 9 that show it's a hard lesson to learn. One point in question is when you have a boss in a casting that needs to be drilled, should the position be centered in the boss, or measured from some datum and allowed to fall where it will? Sadly, the answer is sometimes one, sometimes the other and the only way to tell is think about the job as it relates to the complete sum of the parts, not just the one mounted up for attention now. Somehow, this continues to be a lesson I fail to see the wisdom of, time and again. Hope you can do better.
A Whittle V8 Project Under Construction
No, rest easy, it's not me, yet . Eric Whittle's construction series for his little air-cooled V8 appeared serialized in alternate issues of the Model Engineer back in 1996. I've seen Eric's prototype run, and also seen several others constructed by members of the Bay Area Engine Model Modelers Club at the sadly defunct NAMES shows that were held in Eugene, Oregon, and never failed to be impressed by the little engine's attractiveness and simplicity. This is one of those multi-cylinder engines that you can look at and say, Yes! I could build that! Ok, so there's a bit of repetition involved, but not that much, and it's such a cute little fella. Amongst the correspondence with Nick Jones in the past month, he directed me to the Tejas Dragon web site which is well worth spending some time at if you have ever thought about building this engine. While "Tejas Dragon" still has a long way to go, he's also come a long way and taken some good pictures and short video clips along the way. Definitely a site to keep an eye on.
Barry Jordan's Miniture Machine Tools
Regular readers of the Model Engineer and Model Engineer's Workshop magazines will not be strangers to Barry Jordan's work, but he may be new to North American readers. All Barry's models a working models. They will cut, turn and drill actual metal. All are made from the solid; there are no castings involved. They were recently on display at the Bristol Model Engineering Exhibition where Nick Jones (that name again ) was on hand to take photos. They appear, together with some IC engines, on a page dedicated to the Bristol 2004 ME Exhibition. Pay particular attention to the casting under the chuck of the radial arm drill. Presumably, it's a model of a model casting.