What a month March was! It's also sort of appropriate that I'm posting this page on April first, "April Fools' Day", since I sure feel like one. First, the good news. I had the best birthday party with old friends and new. Lots of red wine and dead cow were consumed and some great jazz played by all the old musos who came along—at least it sounded good to us. If it can get any better, I'd like to know how. Our heading photo shows a different get-together. Motor Boys, David Owen (Australia) on the left and Les Stone (USA) on the right met up for the first time as Les and his wife Donna were passing through Sydney on a cruise. David and Celia, who live somewhat nearby in Wollongong, got together with them for a bite in Nowra (look it up). Needless to say, David and Les talked engines and engine making while the girls probably talked about the boy's limited conversation ability .
Now the not so good. In last month's Editorial, I indulged in a little anti-spam rant. Perhaps it was coincidence, but within a week of that going live, the Model Engine News website was hacked and used to send tens of thousands of spams advertising a Canadian Viagra seller, who naturally denies all knowledge. The mails were sent out with a plethora of different and probably fictitious "from" names, but all had MY email address as the sender. As a result, I got the bounce messages from the target addresses that could not be delivered—this was how I discovered what was going on. As to why I feel foolish, that has to do with how long it took me to determine that it was not just my email address that had been purloined and that the actual MEN site had been hacked. After that, it was a relatively quick job to shut down the injected code that was, in a round about way, sending the spams. I'm being hard on myself here because I'm supposed to understand this stuff. How a non-technical web site owner would cope is beyond me.
Following the clean-up and extensive checking of the 59,067 files on the public part of the web site, I spent quite some time beefing up security. We have an old industry saying that "security by obscurity is no security". In other words, if you have "strong" security, you should be able to tell the world exactly how the security works, without that disclosure compromising the security. Sadly, I'm not that confident, but I do have some hopes that I've closed off enough potential vulnerabilities that hackers will go look for an easier target. Unless that is, this little note attracts a smarter class of sociopath. Even if it does, I've now got processes in place to warn me very quickly.
On the down side, page access is now slower, though hopefully not enough so you will notice. It's also possible that some legitimate non-English speaking MEN readers who use certain translation services will find access suddenly blocked. If this is you, and you somehow manage to read this, email me and I'll see if we can work out something to help you regain the lost access.
To finish up on a high note, my ISP has gracefully admitted to having made an error in his Domain Name Service (DNS) configuration file, so instances of modelenginenews.org suddenly disappearing should now be a thing of the past. I forgive him because it's conforting to know that while a mistake had been made, it's been identified and corrected. Now back to business...
A New Nova
Those cursed with a classical education that included Latin may remember that novus meant new, so are we having a new-new here? Not really. Long time MEN readers will immediately identify "Nova" with the delightful old 4.5cc diesel designed by IJ van Leeuwen in occupied Holland during World War II, and subsequently built by many others including the Motor Boys, and Ken Croft from his own patterns before he became a Motor Boy. The engine seen here was recently completed by Chris Dunn (Australia) who made a few small changes, like changing it from a diesel into spark-ignition engine. Click the thumbnail, or follow this link to the Nova-1 SI description.
A Simple Job
MEN reader, Tim Wescott, had a Cox TD 09 which was way too tight at TDC, so he decided to use the techniques on this web site to correct the problem. In the process, he found more and more problems with the engine. The final butchers' bill for the simple job was a new cylinder with separate head to take conventional glow plugs, a new piston and conrod, plus a new crankshaft and prop driver! Along the way, Tim made three pistons before arriving at an acceptable one, abandoning Cox's ball and socket rod in favor of a two piece aluminum wrist pin carrier pressed into a steel shell.
Tim's photo here shows the retained parts (top) and the manufactured parts (bottom). Tim confesses that his head will only match the tapped holes in the cylinder in one orientation and the exhaust ports tops are not all precisely in line, but despite all that, the reworked engine runs just fine. Having previously made venturi inserts and needle valve assemblies, Tim has now made all types of engine parts except for a crankcase, though he now feels confident that he could tackle a full build and overcome any problems successfully. "Tinkering" like this is a great way to build skills and confidence. There will almost always be problems and finding successful solutions to them is part of the fun and reward.
A Hone Of His Own
I've really gotta stop with these dreadful puns already. The external hones in this picture were made by Phil Wilson (UK), modelled on the Delipana pattern, kits for which are still available from Polly Engineering. Phil is building a nine cylinder radial using a set of CAD plans available from CAD+Modelltechnik Jung (Germany). The tiny hones were made to finish the valve stems for the engine. Phil has put together a great web site to document the build of his radial. Click the link for a quick look, but be prepared to stay a lot longer (we've also added Phil's site to the non-commercial section of our links page).
K Mills Restoration
The Indian made K-Mills reproductions have a rather dubious reputation. They generally run well and start easily, but are neither as robust, nor as well made as the originals. The engine on the left in this photo is a Kumar 1.3cc reproduction that was obtained at a swap meet nearly twenty years ago by Jim Few (UK). It ran, but Jim was dissatisfied with the fuel tank which looked like it came from the K-Mills 0.75. Using the plans from Model Engine Builder Issue #1 as inspiration, Jim machined up a new venturi, tank top, and tank. The engine on the right is an original Mills 1.3 Mk II for comparison purposes.
During the rennovation, Jim disassembled the engine and found that the centre of the crank pin was not in line with the centre of the
cylinder, with only half of the con-rod on the crank pin. This was cured by replacing the inner bush with one where the face is extended by 0.0615". The backplate thickness was reduced by 1/16" and the cylinder fins were cleaned up in the lathe. Jim also squared the exhaust ports with a slot drill and applied a new paint job on the crankcase just to improve the appearance. The piston/cylinder fit however was good and the engine runs free now without the internal stresses that were there before. It also looks a lot better and Jim will remember to take a "before" shot to go with his "after" in future .
Just When You Think You've Seen Everything
Some years back, we were sent photos of a strange two cylinder four-stroke engine to identify. The emails flew fast and furious as we proposed theories as to how the valve system worked and what the missing carburettor must have attached to. All this conjecture stopped abruptly when Ken Croft told us to stop being silly as the item in question was obviously a steam engine! After he'd said it, any fool could see he was obviously correct and we'd allowed ourselves to go off on flights of fancy because the owner had told us it was a two-stroke IC engine. I'd like to think we are all now wiser (we are certainly older), so I've applied open-mindedness to our latest Watzit, but still think it is a spark IC engine. See what you think.
New Books and Magazines This Month
With nothing new being added to The Library this month, I've selected an old publication which is still easy to obtain and contains a wealth of information to model engineers starting out on model IC engine building. The book is The Atom Minor Mark III, by Edgar T Westbury, reprinted in 1984 by TEE Publishing, ISBN 0905100565. Sadly, the publishing history page does not tell us who originally published the book, nor when. Information supplied by a reader tells us that is was a 1947 Percival Marshall publication. The copyright page of the TEE publication has a note to the effect that the Atom Minor was originally designed in 1933. This is both misleading, and wrong. The Atom Minor Mk I appeared in the Model Engineer in 1932. This was a 14cc side-port engine bearing very little resemblence to the Atom Minor Mk III, a rear rotary valve induction engine.
Now you may be asking just how relevant a design that is now almost eighty years old will be today, not mention how applicable the text describing the construction methods and tools might be. The Atom Minor Mk III is admittedly, a bit of a lump as weight goes, but it is a nicely designed rear rotary induction, spark ignition engine (which can be run using glow plug ignition, without modification, contrary to popular belief and at least two Model Engineer articles). Power wise, it would do well in an old-timer of 60" to 80" span and really add to the vintage feel. Regarding the relevance of the techniques used for construction, I have no hesitation in recommending this book to any beginner for the well thought out set-ups and techniques described. Even the more advanced builder might learn a thing, or two.
Format wise, the book is soft-bound, about 7" by 5", with fifty pages containing numerous black and white photographs, illustrations, and complete drawings for each part. The drawings are not your conventional engine plans—something which would be a tad impractical at the size of the pages in question. Instead, each part appears in isolation, fully dimensioned, in the sequence which ETW selected for logical construction. Having built one from these plans, I can attest that the drawings are essentially correct. While the between centers dimension for the conrod is shown a bit short, if you follow the instructions, this does not matter! The sample page here is typical and also a good example of some of the old wisdom contained in the text—note the part describing a technique known as "carburizing" used to increase the wear resistance of the inner surface of the cylinder.
The techniques in the book, in keeping with the time it was written, use only the most basic of equipment and tools. This does not mean they are dated. In fact, they are so basic to model engine making in general that you will find they become your standard approach. Take the main crankcase casting as an example. It has a bore axial with the crankshaft for the front and rear housings, and another at right angles to the first for the cylinder. But this is a desaxé engine, meaning that the cylinder bore axis is offset from the shaft axis by 0.063" in the direction of rotation. This illustration from the book shows a simple plug, angle plate, and faceplate setup used to achieve this alignment. The same approach, with the centerpunch mark central can be used for machining non-desaxé castings. It ensures that the two axies are orthogonal—very important as inaccuracy here increases friction—and aligned correctly with respect to each other. My point is, this book clearly illustrates basic operations in model engine making; just look at any of the construction series on this web site to see this setup used again and again.
A quick look on Amazon yielded one copy from an Amazon Associate at a mere $74.52. Surprisingly, the Advanced Book Exchange had no copies at all, but TEE Publishing lists it as a current item for a mere £5.95 (plus P&P). The Atom Minor Mk III was the second engine that I built and may have been pushing the envelope of my capabilities at the time with regard to work-holding and set-ups, but by following the text, I ended up with a nice example which needs only a new conrod (somehow, I made it too long for the engine to turn over, oops). Way back when, castings were available through the now defunct Woking Precision, but you can obtain a set for £56.00 from Hemingway Kits (UK), who can also supply the book and a full castings and materials kit for £73.50 (including VAT of 20%). I'll give this book Four Stars , missing a higher rating only because I hate the long, delicate 1/4" diameter crankshaft journal; machining that shaft produces more swarf than part!
Engine Of The Month: A-S 55
This month Adrian returns to the British Isles and the smelly, oily diesels we love so much with the sadly short-lived Allbon-Saunders' 0.5cc diesel, known for some reason as the "AS 55" (strangely, we don't think they are at all "smelly", but we'll give you the "oily" one...). Taking full advantage of the World Wide Web as the media, he presents more information about this little engine than has ever appeared anywhere before now. We regret that some dates are more vague than we'd like as we often rely on model magazine advertising to approximate when a certain product appeared, and disappeared. As Allbon-Saunders did not advertise widely, nor frequently, the demise of this lovely little engine is a bit of a guess. Also as usual, if someone out there has definite knowledge, we'd love to hear about it.
Tech Tip of the Month
This month's tech tip was prompted by a diagram I spotted while flicking through an old 1963 issue of Model Airplane News. It showed a diagram of a typical six-bolt cylinder head with the bolts numbered in the suggested tightening sequence. My first reaction was that's all wrong! After a bit more thinking, my outrage was relaxed enough to say it would be correct, but only under certain circumstances. This moved me to examine a few engines in my collection and conclude that what is required is not a sequence, rather a strategy. Hence we now have a How To Tighten Head Bolts page which may help the tinkerers out there (and in here )...
This section is intended to alert you to little things that are hard to expand to a full news item, or cunningly wind into the Editorial, but are worthy of note never the less.
- The People section now has a profile of another pioneer, namely Mel Anderson, scanned and OCR'd from a long ago piece in Model Airplane News by Joe Wagner.
- We have an answer to a Watzit which we rather doubted we'd ever find anything more on. Revisit the Gatehouse of Fleet to see how well we guessed.