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The Machinist’s Art

Author Photo
By Staff

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Stan Ellerbeck's scale Alamo, sister engine to Eric's, running sweetly at last summer's engine show in Portland, Ind.
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Detail of the nameplate on Eric Brekke’s third-scale 4 HP
Alamo, which was crafted on a computer-aided milling machine. The
program file for the nameplate  contained 700,000 bytes of
information.

It’s funny how a little interest can build into something
big. Or, as in this case, something small.

Up until a few years ago, Eric Brekke, Parkville, Mo.,
didn’t have any particular interest in old farm engines. A
machinist by trade, his engine interests ran towards old cars and
trucks and the Detroit Iron powering them. Even so, as his skills
grew, his interests likewise expanded, and he became interested in
scale engines.

About five years ago he launched into his first scale project, a
steam-powered road roller built from plans. With its 100-psi boiler
and two-cylinder engine (complete with reversing valve), the roller
is an impressive bit of work. Satisfied with the roller project,
and with his interest in scales growing, Eric turned his attention
to building a Dick Upsher four-stroke, single-cylinder, vertical
miniature gas engine. When he finished the gas engine in the fall
of 2000, Eric took his scales to the Lathrop (Missouri) Antique
Car, Tractor and Engine Club show. Figuring it was simply a good
opportunity to compare his skills with other scale engine builders
who might be on hand, Eric never could have guessed that one little
trip to an engine show would ultimately launch the creation of the
Alamo engine you see here.

Right side view of the engine, scratch-built, belt-driven water
pump visible in front of flywheel. The aluminum box attached to the
skid is a pressure-sensitive flow control for propane.

Left side of engine, with machinist’s caliper thrown in for
scale. Eric made a special sheet-metal brake to form the cooling
trays.

Alamo impulse

At Lathrop, Eric met members of the Mo-Kan Antique Power
Association (an engine club with members in Kansas and Missouri).
They admired his work, and encouraged him to get involved with the
club. One of those members was Stan Ellerbeck, Excelsior Springs,
Mo. ‘When I saw that model and the roller, I came by and told
him, ‘hands down, that’s the nicest thing here at the
show,” Stan recalls. Stan – also a machinist by trade –
struck up a friendship with Eric, and a short while later they
latched on to the idea of building a scale version of Stan’s 4
HP, circa 1910 screen-cooled Alamo. This wouldn’t be a standard
scale, however.

First off, instead of working at a more standard quarter-scale,
Eric wanted to make this engine at a third-scale. And instead of
making castings, the plan was to craft the engine entirely from
stock materials, machining and fabricating as necessary to build a
finished engine.

It’s probably safe to say neither Eric nor Stan knew just
how much work the project would ultimately entail.

Eric started working on drawings in the spring of 2000, taking
measurements from Stan’s engine and transferring them to metal
stock. The plan was to build two engines, which Eric did, and while
that meant more machining time, it also gave Eric the chance to
perfect his approach on making each component of the engine.

Take, for instance, the flyball governor Eric made for the scale
Alamo. An exquisite piece of work, its complicated construction is
a testimony to Eric’s determination and his skills as a
machinist. The original governor’s flyballs were cast pieces,
but since Eric was working with brass stock, replicating the
fly-balls presented some unique problems. To make sure each flyball
was exactly the same, Eric fabricated his own tools to turn and cut
the flyballs. And to be safe, he made seven instead of the required
six. ‘One of the rules with stuff like this is you build one
extra, if you can,’ Eric says. All told, each governor is made
up from 20 separate pieces.

Three-ball flyball governor is a thing of beauty. Note the front
edge of the crank guard: Eric constructed his own die so he could
form the double radius.

With some pieces, Eric first made a mock-up out of aluminum
billet. The finished valve chests and mixer, for instance, are
steel. By working with aluminum (which is much softer, and hence
easier to cut than the steel used on the final pieces), Eric could
play with the pieces to ensure he found the right technique for
their final fabrication.

Eric made the base plate from hot-rolled, 5/8-inch steel, the
side plates from 1/2-inch hot-rolled steel, and the front plates
from 1/4-inch plate steel, bent to form. To ensure a perfect fit,
he surfaced the base, machining a slight radius into it where the
side plates join so his finished weld (done on the backside) would
be imperceptible after a bit of file work. Similarly, Eric built
the crankshaft saddle from separate pieces, which he set in pockets
in the base and welded in place. This approach meant Eric could
install the crankshaft (which turns on bronze oil-lite bushings)
and the saddles as a unit, ensuring perfect alignment. The cylinder
started as a piece of 4-inch round stock with a 1 -inch center
hole, and ended up with a 2-inch finished bore. Eric then welded
mounting tabs to the cylinder, followed with careful machining,
welding and filing to ensure a ‘cast’ appearance.

The crank guard is another piece deserving mention. ‘I’m
real proud of the crank guard,’ Eric says. ‘I had to make
some dies and manipulate it with a roller. It actually has a rolled
edge since it’s a solid brass sheet.’ Making a die was the
only way Eric could form the double radius at the front of the
guard. ‘It’s all about creative solutions, and that’s
how I solved that problem.’

Creative solutions certainly abound on this project. The oilers,
for example, are handmade. ‘There are some scales available,
but since this is one-third scale it’s a little unusual,’
Eric says. To get around that issue, Eric sourced 5/8-inch sight
glass from Lee Pederson, and then built the oilers around the
glass. There are three different sized oilers on the engine,
patterned from a Lunkenheimer swing-top, and all the detail work on
the oilers was hand filed.

Stan Ellerbeck’s scale Alamo, sister engine
to Eric’s, running sweetly at last summer’s engine show in
Portland, Ind.

While most of the engine is the result of Eric’s prodigious
skills as a machinist, one piece in particular was the result of
modern computer technology: the nameplate. Both Eric and Stan
wanted a faithful reproduction of the Alamo’s nameplate, but
getting one made was another issue. They tried jobbing it out, Eric
says, but they were told it couldn’t be done. The final
nameplate was Stan’s doing, thanks to his familiarity with
computer-aided drafting software.

Starting with a picture of his original Alamo’s nameplate,
Stan then scanned the picture into his computer. ‘I took it and
I made a raster image,’ Stan says, ‘and then put that into
the program. After that, I blew it up on my 19-inch monitor. Each
letter was the size of the screen, and each curve was a point that
I had to mark. There are bizillions of clicks in that thing. It
took me two weeks to draw it.’ There were 7,000 lines of
command and 700,000 bytes of information in the final computer
file, which was then transferred to a computeraided milling program
for final machining on a CNC (computer numerically controlled)
machine. ‘That was our solution to that problem,’ Eric
says.

The 11 -inch flywheels also benefited from computer technology.
Using his computer-aided drafting program, Stan drew plans for the
flywheels, which were then cast by Roger Martin of Morrison &
Martin Engine Works, Benton City, Wash. ‘He did an awesome
job,’ Eric says of Roger’s work. Eric, however, did all the
final machining on the flywheels.

The two engines were finished earlier this year, and since then
Stan’s taken his scale Alamo to a number of shows, running it
every time. He figures it’s got about 100 hours running time on
it now, and he says it hasn’t missed a beat. Stan had his scale
Alamo running at this summer’s engine show in Portland, Ind.,
set up next to his full-size Alamo for comparison. It was an
impressive sight, drawing a constant stream of admiring
onlookers.

Detail shot of engine bed, crank assembly and oilers. Note the
almost invisible joint between the side plate and the engine base.
Numerous hidden details abound on the engine. For instance, Eric
and Stan spent an entire day experimenting with the fore and aft
position of the exhaust linkage’s pivot point, making sure it
was ideally positioned for proper lift on the exhaust valve.

Looking Forward

Not one to sit around, Eric’s already moving on to his next
project, a scale Callahan ‘cam stopper.’ Eric says he’d
like to build a couple and sell one. Although happily employed as a
machinist, he’d like to turn his interest in scale engines into
a full-time job. Given Eric’s eye for detail and quality, and
his ample reserves of patience, that sounds like a sure bet for the
future.

Richard Backus is editor of Gas Engine
Magazine.
Contact him at 1503 S.W. 42nd St., Topeka, KS
66609-1265, or e-mail: rbackus@ogdenpubs.com

Gas Engine Magazine

Preserving the History of Internal Combustion Engines