Hello again. As I write this month's article, I'm preparing to attend the 15th Annual North American Model Engineering Society Exposition (NAMES) in Southgate, Mich. I'm excited at the prospect of seeing many of my good friends, and I hope to make some new ones along the way. I'm also looking forward to seeing what new models have been built and what new ones will be offered for sale.
Over the years, I've seen many different kinds of models at NAMES. There are steam-type models (running off compressed air) of many different kinds (such as slide-valve models and walking-beam models), and of course there are four-stroke (and a few two-stroke) internal-combustion-type models.
However, I've yet to see any diesel-type models. I've never had the urge to build a diesel - is it the same for everyone else? Is it because of the high compression? Or is it the fuel used to fire a model can't be cut down? We find models running off propane fuel (these are great for indoors), Coleman-type fuel and fuels with additives (WD-40), and then there are models running on plain gasoline.
There are radials and multi-cylinder models, and hopper-cooled and air-cooled models. At NAMES, you find everything from complete models to models in progress - and casting parts waiting for the next mold to pour.
Along with these, you'll find model bar-stock engines and engines crafted from imagination - such as engines built from air compressors.
Model flame-licker engines (air-cooled and hopper-cooled) make the show, as do Stirling engines.
Then there's the fine, detailed workmanship in train components, ships and boats. There are cannons, rifles, pistols and even a Gatling gun or two. A local industrial arts class builds items and brings them to display, and it makes me feel good to see younger people enjoying the hobby. And yes, there are some girls in these classes, also.
The NAMES show brings people in from across the U.S. and a few from the United Kingdom, as well. Models and model building have been popular in England for some time now, and we are just starting to catch up.
Vendors are another interesting aspect of NAMES, including casting vendors, bar-stock vendors and vendors of tooling items and metals. These fellows travel miles to come to this show, and they hope they sell out every item they bring. It's fun to see what is available for the home hobbyist and part-time machinist, and these folks are some of the ones making this a great hobby.
Next time, I'll touch on some of the items at NAMES that caught my interest. Is this hobby great, or what?
From Rusty's Mail Bag:
18 and Counting
These engines were all built using casting kits from suppliers throughout the U.S. Each one was built using the blueprints furnished, but there is quite a bit of extra brass.
The bases were made from white oak, black walnut, white mahogany and purple heart. Paint is enamel over gray Rustoleum primer. The pin striping is done with a J.C. Whitney roller applicator. Other details are applied with spray stencils and an airbrush.
Paint colors are chosen based on what seems most pleasing at the time. Since the engines are built to give joy and satisfaction to the builder, what difference does the color make?
After each engine is completed, a brass plate is added giving the builders name and year completed. These plates are of my own design with computer-generated lettering and are made by a local trophy shop for approximately $10 each.
I do all my painting before assembling anything. Mating surfaces are masked with masking tape and bolt and screw holes are covered with discs punched from the masking tape using regular leather punches. Any pinstriping and stenciling is done at this time.
One further word about painting: Any machined or fabricated cast iron or steel part eventually rusts. Those polished faces on flywheels are beautiful until the humidity increases and the temperature drops, and whammo, rust covers everything. It seems to me the most practical thing is paint everything possible.
I was handicapped for a long, long time by having to apply my time to a regular job. After retiring 20 years ago, engine building seemed to be a good choice for me. Since then, I have built 35 engines, one grist mill, made numerous parts for friends (turning flywheels, boring cylinders, turning crankshafts, making camshafts, etc.) and helped others complete engine kits when they got 'stuck' on the job.
These have been fun years, and associated with this I have met some of the friendliest and most knowledgeable people on earth. I hope this encourages others to seriously consider building model engines.
And before the question is asked - no, these are not for sale. But think of the joy these will bring to my family and grandsons in years to come.
Garland R. Jobe, 2114 Alamance Church Road, Greensboro, NC 27406-7917
I have been working on engines for 65-plus years, and I have built and repaired models for 20 years.
My first model was made from a little Brunner air compressor, which made a great model. I have since made some kit models, including Associated, Economy and Gray engines.
I have found model engines have to be loose enough that the flywheels rock back and forth several times when pushed against compression. One way to do this is to use one O-ring on the piston. I have had some pretty high-powered model men tell me this won't work or last, yet my Associated has run several years on a hardware O-ring that cost 20 cents.
The O-ring needs to have enough wall tension to hold itself in the cylinder when vertical. I have a model with a 7/8-inch bore, and I used a 7/8-inch OD O-ring with a 3/32-inch cross-section. It must have side clearance, and it must have clearance at the bottom of the groove so that compression can get behind the O-ring and push it out to the cylinder wall. When the engine is coasting, there is very little drag, and that is what makes a long-coasting engine. O-rings will not work in a ported cylinder. A setup like this usually needs no cooling. My 7/8-inch bore has a cast iron cylinder and head -it will run all day and won't burn your finger. With kits, don't remove any more material off the flywheel rims than needed to smooth them up.
Also, don't use Torrington needle bearings for main bearings on models, as they rough up most shaft material unless the shaft is super hard. Plus, they're noisy.
On models such as the 1-1/16-inch bore Economy, I cut 1/4-inch off the stroke. This reduces friction, and the flywheel will pull the piston over that first compression stroke - the flywheels turn faster and coast longer. I run all my models on propane, as they run cleaner.
Raymond C. Taylor, 20 Pecan Drive Pensacola, FL 32534
These tips are for your thoughts only, and your fuel lines may vary. - Rusty Hopper