By Staff
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Birk operating the model sawmill at Utah Antique Machinery Association's show in Salt Lake City in September of 1986. The mill saws logs 4' to 6' in diameter into lath size boards. It was powered by a 6 HP Hercules engine owned by Harold Probasc

557 East 3460 North, Provo, Utah 84604

Birk Petersen, secretary of the Utah Antique Machinery
Association, builds another one! This time it’s a one-quarter
scale, working model of an American sawmill.

It all began a year ago last summer when Bruce Rogers, president
of the Utah Antique Machinery Association, said, ‘What we need
in our association is a sawmill.’ That’s all it took to get
my mental gears a whirring. A full-sized sawmill is a bit
cumbersome to store and transport to meets when one lives in a
subdivision and uses a Dodge Aspen station wagon for transportation
so the decision to make a model was quite easy.

I located a couple of people who had sawmills and decided to
copy one owned by Bud Parker in southeast Salt Lake valley. Bud,
being an old machinery buff himself, was more than willing to let
me take measurements of his mill. I spent several days at Bud’s
sawmill making a detailed, dimensioned sketch of every different
part of the mill. Photos were also taken to capture fine details.
On Xerox copies of the sketches, all dimensions were reduced to
one-fourth original size and marked in red. Using the reduced
dimensions, wood patterns and core boxes were made. There were over
sixty of them. Using the patterns and core boxes to form sand
molds, aluminum and bronze castings were made, well over a hundred
of them. The castings were then machined as required.

I make my own gears, and there are twelve of them in this little
model. It would be much easier to buy gears from someone like
Boston Gear, but in small sizes they would not be spoked and they
just would not look right.

When the original mill uses 1/8 diameter
cotter pins, and you scale the size down to one-fourth, it becomes
1/32′ diameter. The 1/32′ diameter cotter pins are not
readily available at the hardware stores so what does one do?
Simple, just draw file a piece of .035′ diameter wire to half
round, bend it around another piece of wire to form the eye, and
snip it off. Presto! You have a 1/32′ diameter cotter pin.

Small bolts available at hardware stores do not look right
either. The heads have screwdriver slots rather than being hex
shaped, and the nuts are way out of proportion size-wise. Most of
the bolts used in this model were procured from Cole’s Power
Model Shop in Ventura, California. However, sizes that were not
available were machined from hex bar stock procured from PDM’s
Steel Service Center in Spanish Fork. Total construction time was
less than a year of spare time, and all of the work was done in my
home workshop. What will the model sawmill be used for? I plan to
take it to antique machinery meets and demonstrate it. (Play with

At the time of this writing, I have just completed a model
storage barn in my backyard that will be used to store and display
some of my gadgets.

What will my next project be? It’s a lot easier and faster
to design something in your mind than it is to find the time to get
it built, so there are many things I would like to build. One thing
that has my interest now is an antique, gasoline engine-powered
‘Rube Goldberg’ type ice cream making machine complete with
an ice grinder and some sort of music making equipment, and a few
other mechanical parts that do no useful work at all except amuse
people. Whether it will materialize or not, only time will

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