Model Engine News: April 2006


Special Features:

   Vale: Hamilton Upshur
   Fig Tree Pocket Marine Twin Completed
   Four-stroke Diesel
   Camm Air Engine
   Another Sugden Running
   A Hone of his Own
   Little Dragon Construction
   Exoticia

Regular Features:

   Editorial
   New Books and Magazines This Month
   Engine Of The Month: Taipan 2.5 "Goldhead"
   Tech Tip of the Month
   Standard Stuff

All material on this web site is Copyright (c) of Ronald A Chernich 1999-2006, 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's hard to believe a quarter of 2006 has passed already, but calenders do not lie: it has! The start-up company continues to consume my waking moments at a furious rate, leaving me little time and no energy for model making. Even finding the time required to compose these pages has suffered this past month, but the web-stats show that March has been the busiest time ever for Model Engine News with my long suffering ISP responding gallantly to my urgent plea for more bandwidth! Hopefully, the new allocation will see us through for a while. March has also been a busy month for sales of the MEN CD. This is especially good as it's sales of the CD that keeps the site alive—so to new and old Members alike, thanks! We were just short of 1 million page hits in March. I think that mark will be broken in April.

When I re-read my work in these pages (yes, I really do), I recognize that my writing could be cleaner and clearer. One indication of this lack of clarity and readability is the number of times I feel the need to resort to bracketed asides (like in the previous sentence (bugger, I've done it again (just as well software engineers understand nesting))). In an effort to reduce this annoying and distracting habit, some scripting has been introduced to replace the worst of the meaning obfuscation caused by parenthasised asides. Just hover over the double underlined text and you'll get what would have otherwise been inserted in brackets. I hope this helps, and that I don't have to resort to double underlined terms in the popups!

Vale: Hamilton Upshur

Sadly, Hamilton (Dick) Upshur lost his battle with cancer on Sunday March 26, 2006. Readers of SIC will recognize his name from all his stationary engine construction articles that appeared there over the life of the magazine. A native of Virginia in the USA, Dick was born in 1924. His first model engine was a GHQ, built from a kit in 1937, making it also his first home-built engine. Even while serving with the Army Air Corps in WW II Italy, he managed to design and build model engines that he shipped home. One of these, a farm-type, was run and exhibited until 2003. Returning home after the war, he gained a BSc from Virginia Tech, followed by a MSc from the University of Michigan before embarking on a career as a designer of aircraft actuator devices. During summers while at university, he worked for the Indian Motorcycle Agency, and flew control line and free flight models, powered by his own engines. In addition to designing and building model engines, he was a private pilot, musician, and proud owner-restorer of a straight-eight Bugatti boat-tail racing car.

His career as a contributing author began in 1956. In addition to SIC, Dick's work also appeared in the Model Engineer, American Modeller, Modeltec, Sports Car Club of America Magazine, Gas Engine Mechanic, Bugantics, Par Sang, and Model Engine Builder. A feature of his designs that always struck a chord with me was his philosophy of simple construction with no castings required. A quick scan shows:

As well as these full construction series (the SIC references above show only part one of each), Hamilton Upshur provided occasional articles on topics like piston and ring design, and how to make a GHQ actually run—taking him full circle to his first engine. It's always sad to see the passing of model engineers like Dick, but there is comfort in how his name will live on through his published designs.

Ref: Model Engine Builder, Elmwood Publishing, USA, Sep 2005, p6.

Fig Tree Pocket Marine Twin Completed

Last month, we saw the progress being made by Malcolm Beak (UK) on his marine adaptation of the Fig Tree Pocket Twin that appears in the Motor Boys' Plans Book. This engine is now complete and undergoing trials. If you look at the drive-god end of the flywheel in the photo, you will see that there's no doubt: this engine is running happily. Malcolm reports that it required a few strong words to arrive at this state. Visit the Engine Gallery, page 8 for the full story.

Four-stroke Diesel

Here's a slightly unusual engine from German engine Builder, Armin de Vries. The VT-1D is a four-stroke compression ignition engine that uses an eccentric crankshaft bush to vary the compression (a technique used by one production engine that I know of produced by Norwegian engine designer, David-Andersen). Armin's website (in German and English) shows the extent of his efforts with replica Kratmos, a side-valve four-stroke, a tiny hit 'n miss engine, and many others. Well worth a look.

Camm Air Engine

This compressed air driven engine is a five cylinder radial designed by FJ Camm. It was recently completed by Mr Olle Erisson of Sweden. Olle reports that it took only 20 years to complete. After starting and finishing most of the parts, the project halted for want of a supply of the phenolic material called out for the pistons. On reading about the Pachasa air engines in these pages, the project came out from under the bench and was completed and running with a couple of evenings (I bet we all have a few projects like that). Olle reports that the engine will swing a 13-7 APC (his biggest available prop) at about 2,200 RPM on 8 BAR of pressure using Delrin pistons.

Another Sugden Running

Les Stone has joined the ranks of running Sugden Special owner-builders. Les commenced his project in the new year using one of Andrew Coholic's sand-cast cases. Along the way he has changed a few aspects of the design; some obvious, some not. For more details, visit the Les Stone Tribute Page.

A Hone Of His Own

Last months Tech Tip showed Nick Jones' innovative jig for holding odd shapped pieces of metal. The item in question was one half of a small, Delapena-like external hone. As you can see, Nick has finished the tool in fine style. The tool is designed to have replaceable stones and guides. The height of the guides and stone holders are designed for a relatively small range of stock size so that they are close to diametrically opposite each other in operation. Somehow, my tool never seems to have the right size in it for the job at hand, so I'm forever swapping. Nick has produced three tools, which increases his chances considerably.

It's very satisfying to use a tool that you've made yourself, and that does the job well. To add to the beauty and enjoyment of using his hones, Nick has made a very attractive fitted case for them. After figuring out the trick of using a "truing stick" to bring the stone and guide into alignment, he reports that the tool has produced a fine finish on his ETW Kiwi valve stems with a variation of less than two tenths (0.0002") over the length. We should expect to see the Kiwi running soon, he says.

And the pun in my title for this piece is what Nick gets for the pun in the name he's given to his tools .

Little Dragon Construction

Even though work pressures have precluded shop activity this past month, I have managed to add words to the last of the pictures taken during the build, so you can now read about the unusual way of making an aluminium piston suggested by designer, Roy Clough Jr, making the cylinder head, and the rear rotary valve.

New Books and Magazines This Month

Only new book adding to the stress on the foundations of The Library this month was most kindly sent by Ron Moulton. Appropriate since, as reported last month, he has been largely responsible for its content and accuracy. This is the auction catalogue for The OFW Fisher Collection of Model Aero Engines and Aeroplanes that will be conducted this month, April 21st, 2006, on the Isle of Man. Ron emailed me this month to report that even though gremlins resulted in some printed in accuracies (reported last month), the actual on-line auction site descriptions have been corrected.

Even if you can't attend the auction, this little booklet is worth acquiring. It is printed in full color and provides descriptions of the 283 items on offer, with nice, clear photographs of 53 of the more unusual ones. Together with details of the auction company and its history, a page describes Peter Fisher's life, accomplishments and association with the Island.

Engine Of The Month: Taipan 2.5 "Goldhead"

This month, following requests from readers, we look at the Taipan 2.5cc, twin ball-race, Schneurle ported, rear-exhaust screamer. Even though the engine dates back to the early to mid 1970's, it is more common than a lot of other Taipans due to its export in quantity to the USA. A quick look through MAN issues of 1975 showed the engine appearing in plans for 1/4 Midget pylin racers and C/L Goodyear models, showing a high degree of market acceptance.

Tech Tip of the Month

Here's a simple trick that may help you do a better job if you are someday faced with the same problem I was. A friend had a new, unused ED Hunter crankcase that the factory had drilled for the backplate attach screw holes, but not tapped (the cylinder holes had been both drilled and tapped). This may explain why the case had lain, unused, since the 1950's. My job was to tap it for him. I happened to know that the tap size was 6BA and a check on the drilled holes (#43) confirmed this.

Normally, I will clamp up a case under the mill/drill, drill the hole to be tapped, then use the tap in the drill chuck, rotated by hand, to ensure the tap is started squarely into the hole. I then release the tap from the chuck, fit a small tap handle that provides a "sensitive" feel, and finish tapping the hole. This accomplishes a couple of things. First, it assures that the screw is vertical to the machined surface, so the underside of the screw head will press evenly against the backplate. Perhaps even more important, a tap that does not start squarely into the hole places you in peril of breaking the tap as it tries progressively to deviate from the path of the hole. That can ruin your whole day.

The delicate case could have been clamped up in the mill vise, but it was much easier to make a guide that would hold the tap vertical relative to the machined backplate mounting face. A quick hunt in the scrap box found a short piece of 1/2" square steel bar that already looked like Swiss cheese. This was drilled #33, the clerance size for 6BA, near one end. As seen in the photo, with the bar diagonally laid across the case rear, the hole provided a guide to ensure the tap entered the holes squarely. The job was then quickly and accurately finished—in fact, it has probably taken me longer to describe the problem and cure than to do the job! Perhaps it may help you someday.

Exoticia

Yes, it's a four-in-line Taplin, harking from the same era as the Taplin Twin Prototype. Photographs of the original engine appeared in British magazines of the 1950's, and it is entirely possible that this is that engine. The carburettor is obviously a contemporary Taplin unit, and the heads are remarkably "bright", but I recognize the drain-pipe elbow of the brass inlet manifold and who'd replicate that willingly? The photo was sent in by a very talented model engineer who did quite a lot of work for the late Manuel de Rancougne. Tom kindly mailed—at great expense—a thick pile of color prints showing engines that were in Manuel's collection, and others. Digitising and cropping these will take days, but a start has been made and can be viewed on a new pre-auction collection page.