The old adage about ...never rains—it pours... was proven again during the past month. Readers may recall that a year ago, we were in the clutches of a seven year drought here, with levels in the dams under 20% meaning we were drinking the mud. Increasingly elevated water restrictions were applied and I came to be of the opinion that they would never be lifted again. Well, we got some good rain at the beginning of the year, then some very heavy and unseasonable downpours during May. Local TV showed a tumble dryer floating down a major highway and a lot of people were subjected to a lot of property loss. As usual, some drivers saw flooded roads and carried on regardless with the inevitable, tragic results. When the skies began to clear, two of the city's three reservoirs were 100% full, with the spillways open. The third is the big one and even that is at 60% capacity. However the government has decided not to lift the water restrictions "at this time". Sometimes I hate being right.
So here it is, the first day of winter in the southern hemisphere, and not all that cold compared to other years past. But cold enough that trips to the workshop hold little appeal, so we'll make do with words instead. There are quite a lot of them in this month's release with whole sections of the website getting a makeover. The easiest way to see what is new, or changed, it to have a look at the New and Changed Index. This page is generated automatically every month, so if you are not reading this in June 2009, it will not reflect the changes mentioned. Next, I hope you are all sitting down because I'm about to say something nice about Microsoft.
Last month, with my professional hat on, I took a look into the new version of Microsoft's Internet Explorer, dubbed IE8, being their eighth major try at getting it right. We have been struggling with trying to provide support for all browsers in the Annotation Client Facility we are building here at the eResearch Labs of the University of Queensland and were close to calling the job impossible. IE8 has saved the day. Our problems have been caused by the way IE builds up its "model" of the HTML pages you browse to. This model is called the Document Object Model, or DOM for short.
The World Wide Web Consortium (W3C) has a set of standards for the DOM which is followed by every commonly used browser, except IE. We need a browser independent way of navigating around a displayed page, capturing the location of sections highlighted by a user, and inserting new words and pictures dynamically into the display. IE8 is still a long way from being W3C compliant, but the designers seem to have recognized the pain their lack of standards support is causing, or perhaps the falling popularity of IE has caused a rethink. Regardless of the cause, in IE8 Microsoft has made it possible for frustrated developers to extend core behaviour of their non-standard DOM so it can be coerced into playing nice with code written for other browsers (Firefox, Safari, Chrome, Opera, etc) and this is what we have done. It's not perfect and probably never will be, but it is also probably close enough! And Microsoft has provided a very, very good debugging and development tool as part of IE8. It also does an excellent job of rendering fonts—something Firefox and Google Chrome are less good at. I'd say that IE and Apple Safari are on par in this department. So there; IE8 is a good product and well worth upgrading to, in my humble opinion.
The Members' update file for June is amazingly large due to the number of photographs added this month (260 in total). Sorry 'bout that, chief. If you have trouble with the download, it may be time to buy an upgrade . It's also been suggested that I change the DVD distribution to include a bit torrent client specifically for keeping the Members' off-line copies in sync with the main site. This would ease the bandwidth requirements imposed by the downloads and make the download process more robust for users. Very good suggestion but a lot of work though. Nevertheless, I'm considering it. Now down to business...
If you can arrange to be in the Bay area around the middle of July, make plans to drop by the Western Model Engine and Model Exhibition. The show is hosted by BAEM—the Bay Area Engine Modelers and sponsored by our friends at Model Engine Builder. The exhibition will take place at the Vallejo Veteran's Building at 420 Admiral Callaghan Lane, Vallejo California, on Saturday July 18, 2009 from 9 AM to 5 PM, and Sunday July 19 from 9AM to 3PM. BAEM expect to have exhibited all types of model engineering, including model steam engines, model locomotives, model internal combustion engines, Stirling engines, tanks, tether cars and model aircraft engines. The suggested donation is $7 for adults over 18 and $10 for families.
Amazing how things cluster together. After writing this month's Book Review and mentioning the connection between the book and my adventures building a Quorn Tool and Cutter Grinder, an email arrived from Joerg Hugel to let me know that he has posted some files which detail analytical methods he has developed for performing Quorn set-ups that will be of interest to Quorn builders. These are available from the Yahoo Quorn Owners' Forum created and moderated by our old friend, Carl Carlsen. Carl also maintains some other forums that will be of interest to model engine builders. You'll find links to these in the Forums Section of the Link Page.
Test your model engine knowledge: who was the first commercial manufacturer to offer reed valve induction? That leads to the interesting question of what is a "reed valve"? To me, the name reed implies a flexible petal, secured at one end, free to vibrate at the other—just like the reeds used by the woodwind family of musical instruments such as the Clarinet, Saxophone, or even the Bagpipes, to name but a few. These reeds are cut from cane, hence the name. So strictly speaking, if we take that as our definition of a reed valve, then Cox engines don't qualify! Their valve is totally free, operating as a flutter, or clack valve. Besides, the first so-called reed valve Thimble Drome did not appear until 1952 and we have many commercial automatic induction model engines pre-dating that. I'll give an answer next month, but feel free to email with your opinions before then and we are especially keen to hear from readers familiar with European model engines. In the interim, get the lowdown on Automatic Induction from the latest part in Gordon Cornell's Model Engine Development series.
The series is now approaching the planned end with the last part dealing with testing procedures scheduled for next month. But Gordon's arm could be twisted to extend the series, if the demand exists. I can look at the server logs and see that the series is being read, and re-read, but this does not tell us what the readers actually think about it. Is anyone building a Super Fury, or planning to? Has the series given anyone an idea which they have carried through into action? Please drop us an email through [email protected] letting us know. Publication of the series has been a lot of effort for Gordon and myself and we both want to know if justification exists for further parts. It's up to you...
While we were editing Part 7 of Model Engine Development, Gordon asked if I had any photographs of the late Ron Warring we could include, given how much he contributed to the understanding of model engines through his Aeromodeller Engine Review series (127 in total), and other series such as his experiments to quantify break specific fuel consumption. This I did not have, so I contacted Ron Moulton, a past editor of Aeromodeller and many, many other works associated with the hobby. Ron is still searching through shoeboxes, but he did mention that it had been his sad duty to write Ron Warring's Obituary for Aeromodeller back in 1984, suggesting that that issue would at least provide a picture, even if the quality might not be all that we desired. While reading through this piece, I was astounded with what Ron Warring accomplished, so I asked Ron Moulton to review and update it so others too could appreciate his creativity. Click the thumbnail of Ron Warring with one of his Wakefield models to read Ron Moulton's tribute to his colleague and friend.
This led me to think about all the people whose contributions to model making and manufacture have been added to this site over that past eleven years. There are so many that I can't find them easily, so what chance do you have? The answer was yet more metadata that allows an automated process to build a People Index which lists where you can locate words on this website about the famous and the not-so-famous, both living, dead, and not quite dead. A link to the index has been added under the people item of the left-hand navigation menu. It makes the names in that menu rather redundant, so I may remove these in time.
Last month, we started a new Watzit page with pictures of an old Japanese sparker that had been sent in by a reader for identification. I hadn't a clue what it was, so asked our small group. Adrian Duncan and David Owen responded and I cobbled up the information by merging text from their emails. I got it Really, Really, Wrong. Adrian wishes to go on record as stating that his initial message was based for the most part on information received by email from Alan Strutt of England and that when pasting that information into his email to me, he omitted to credit Alan as the primary source and writer of that information. As a result, the page went live without due credit going to Alan. Adrian says that this was an inexcusable oversight on his part and he accepts full responsibility for it. He wishes to apologize openly and unreservedly to Alan for this error.
Worse, in my mash-up of the two responses from Adrian and David, I compounded the situation by starting with David's identification of the engine as a KE model, then finishing with Alan's advice (via Adrian) that it was almost certainly a KD model. Adrian wants it made clear that at no time did Alan identify the engine as a KE model, nor did Adrian support such an identification. This piece of confusion was totally my fault. Alan has since provided incontrovertible evidence to the effect that the engine is actually an earlier KD model made by the same company. Needless to say, the page was corrected as soon as this came to light in the third week of May and I now have crow coming out my ears. Reality is restored; please adjust your memories accordingly.
The annual Harrogate (UK) Model Engineering Exhibition was held in May and we have Ken Croft and Barrie King to thank for being our surrogate model engine eyes at the event. As well as the Usual Suspects, there were a couple of rather nice surprises in this year's offerings. When you visit the Harrogate 2009 page, note that short descriptions of the photos have been included as "hover text", meaning you need to move the mouse over a thumbnail and wait a second or two for the description to appear. As usual, click on any photo for a large size image.
New Books and Magazines This Month
My workshop notebooks tell me that in July 1996, I was close to completing my Quorn Tool and Cutter Grinder and was faced with the problem of how to wire up the motor so that the direction of rotation was switch selectable. I consulted my old engineering texts, but while these provided any amount of math regarding efficiency and loss calculations, they lacked the little piece of practical information I needed. Knowing that the Workshop Practice Series of books had a volume on electric motors, I toddled up to a city bookshop for to see if this tiny volume could help where the heavy duty texts had not. The answer was yes. We are constantly told that a good picture is worth a thousand words. Electric Motors, Number 16 in the Workshop Practice Series, proved this yet again as it contained a drawing so informative by itself that I copied it onto the back of an envelope and had the motor wired and working that night. With the need passed, I neglected to buy a copy of the book and have felt mildly guilty about it ever since. So when the author asked if I'd like to review the new, second edition of his book for MEN readers—issues of gratefully received graft aside—the decision was a complete no-brainer.
Electric Motors, Number 16 in the Workshop Practice Series, by Jim Cox, ISBN 1-85242-914-2, was first published by Argus Books in 1988. Between 1990 and 2003, it went through eleven reprint runs, indicating it has been a popular title in the series. The 2006 Second Edition was published by S.I. Model Books (England). Although much original material remains, this is a truly substantial revision reflecting how technology has moved on since 1988. Today, you can expect to encounter stepper motors, variable frequency Drives, and phase converters in amateur workshops, so Jim has expanded his book to provide information the modern model engineer is likely to require on the subject.
The book has 152 pages divided up as ten chapters, plus an Introduction, the obligatory (and sensible) Foreword on Safety, and an Index. It is well illustrated; the drawings are clear and while the black and white photographs can be a bit "grainy", you can always see what the author is getting at. As I've noted before, the audience for any book decreases by half for every formula it contains. Jim Cox has managed to keep this to a minimum, but this is a subject which really needs math for any kind of real understanding; you have been warned. Chapter One is titled "A Few Basics" and makes sure the reader knows (ahem) a few basics of alternating and direct current (ACDC for metal fans). The following chapters deal with the different types of motors we are likely to encounter in the home workshop and second hand industrial market, together with appropriate controllers, generators, tips on using "scrap" motors, and some simple test equipment.
Chapter Two does a good job of describing the common induction motor, both single and multi-phase. Chapter Three describes various controllers for them, and how to connect them to the AC supply. A really good aspect of this book is the International approach the author takes. His descriptions encompass both 220/240 volt, 50 cycle countries as well as the 110/120 volt, 60 Hz ones. This also extends to dealing with three phase where the voltages rise to 380/420 and 220/240. He explains star and delta configurations, capacitor start/run, and ways to safely and efficiently run a three phase motor from single phase. The induction motor controller chapter closes with up to date information on Variable Frequency Drives (VFD) which are finding more and more favour in the home shop as a way of providing smooth, variable speed drive at high torque.
The section on commutator motors includes details of the newer, more esoteric things we are now encountering such as stepper motors and motors with disc rotors. This chapter includes circuits for home-brew drives for these, including the types we are likely to scrounge from junked disc drives and the like. The remaining chapters introduce generators, electric breaking, and good advice on the sort of couplings typically found between a motor and the shaft it is driving. A chapter for scroungers lists sources from which you might liberate usable motors, along with their restrictions and limitations.
So is this the only book you'll need on the subject? Perhaps, and perhaps not. The subject is very, very broad, and complex. Jim Cox has done a good job providing the material you'll need for a basic understanding. This may be all you'll ever need, or may provide the background knowledge you will need should you begin evaluating more advanced texts. I was unable to locate a copy of the first edition for comparison, but there is evidence that new material has been added throughout. For example, Chapter 3, page 46, contains a reference to Figure 1.15 which obviously should be Fig 1.18c suggesting new illustrations and words have been inserted to Chapter One that invalidated a reference written for the first edition. This kind of error is a proof reading problem that falls on the sholders of the publisher, not the author, and I spotted another, but failed to record where it lies. Nevertheless, I have no qualms about ranking this as a Four Star book for model engineers. Recommended, and available from many sources, including Amazon, for $22.95 .
Engine Of The Month: The Hope Saga
This month, we begin The Hope Saga by Adrian Duncan, in collaboration with Alan Strutt and David Owen. This series of engines came out of Japan and today, are little known. The authors hope (sorry) their series will remedy this. Part One this month provides the company background and the scope of the products they made for pre-WW2 domestic use and the post-war domestic and export market. Future parts will examine the engines in more detail. The authors have poured a lot of effort into making the account as accurate as they can, but make no claim to omniscience and welcome further information.
But wait! There's more... Checkout the New and Updated list of The Finder for other, well, err, new and updated engines. And visit Page 15 of the Engine Gallery for a very nicely made Topsy .375cc diesel from the UK. There is also a new Watzit to puzzle over.
Tech Tip of the Month
During the past month an email arrived asking a question about making skew gears which assumed I'd know which page on this site the question related to. Yes, I should, but no, I didn't! So a little Skew Gear How-to page has been added that pulls together the information through links to past pieces on the subject. I know this will help me and sure hope it helps someone else as well. If you've not considered it before, you'll discover that making perfect helical gears is difficult, requiring some rather special equipment. But making perfectly acceptable, workable skew gears in model sizes is rather easy.
Another tip that occurred to me while composing this month's book review is the value in keeping a Workshop Note Book. You never know when you'll need to refer back to something, for yourself, or someone else. This page shows the development of some soft-jaws for my bench vice (and yes, I had to stare at it a while to figure that one out), followed by I have no idea what, with details for a Johnson NVA at the bottom and a Johnson-like spraybar above. Note the rather unusual UNF 8-36 thread on the Johnson, and the use of a slot rather than a hole as the fuel jet. Some reviewers have credited this slot as the "secret" of the Johnson performance. I do a lot of little jobs like this, making replacement parts for friends. Having the rough sketches all in one place gives me some chance of finding them if they are ever needed again.