HOW DOES A SHINGLE MILL WORK?

By Staff

5408 Genessee Street, Lancaster, New York 14086

In the March-April 1978 of GEM, J. M. Huckabee asked ‘How
does a shingle mill work?’ I hope this short article may help
him, and others who often wonder the same question.

Before I go into the details of these mills, it should be
remembered that just like gas engines and tractors, no two
companies build shingle mills the same. Each company came up with
their own novel ideas which were supposed to be better than their
competition. The exception to this rule is the Chase Turbine Mfg.
Company, and the Lane Mfg. Company whose shingle mills were about
identical.

There are chiefly two different types of shingle mills, the
‘Vertical’ and the ‘horizontal.’ This refers to the
position of the blade. Often the ‘horizontals’ are also
called ‘merry-go-round’ shingle mills. The mills made by
Chase Turbine Mfg. Company, American Sawmill Machinery Company and
DeLoach are good examples of this kind. Good examples of the
‘vertical’ kind are the ones made by the Lyon iron Works
known as the ‘Ireland’, Chase Turbine Mfg. Company, Lane
Mfg. Company, and the Trevor Company.

The blocks of wood (bolts) to be sawn were held as a carriage
which fed them into the saw. The saw always cut with the grain, of
course, but the blocks were either held sideways and cut through
the length, or the block was held endways and the saw cut through
the ends from one to the other.

The carriages were either fed into the saw by hand, by the use
of a rock and pinion, or a crank or bull gear and a connecting rod.
I believe the type using the crank and connecting rod was the most
common. A good example of this type of feed is found on the Ireland
mill built by the Lyon Iron Works. All shingle mills except the
hand feed, used simple friction clutches to engage and disengage
the carriage feed.

The block feed on the carriage is quite a simple affair in
principle, but is often complicated by many parts. The dogs which
hold the blocks are toothed wheels mounted on a rotating shaft. By
the use of a rotating eccentric and a tapered wedge, first the top
dogs rotate more than the bottom ones, to put the taper in that
shingle, then as the carriage returns, the eccentric is turned 180
degrees and the bottom dogs rotate more than the top ones, thus
adjusting for the taper of the next shingle. This is how the
Ireland mill operates. Many of the ‘horizontal’ mills
simply had a pair of knives with teeth on them which closed, on the
ends of the blocks, griping it like fingers. After each shingle was
cut, these knives or dogs would be opened, allowing the block to be
dropped to a pre-set stop plate, which would set it up with the
right taper for the next cut. The only ”vertical’
shingle mill using this type of dogging is the Trevor made in
Lockport, New York. Of course, there may be many others which I
don’t know about.

The Ireland, Chase and Lane were the best of all the shingle
mills being built from the 1890’s to the 1920’s. This could
be called the ‘Golden Era of Shingle Mills.’ It was during
these years that the shingle mill enjoyed its greatest popularity
and became a simple, efficient machine, and after this period,
began decline in both popularity and advancement. Shingle mills
still exist which are known to have been built in the 1850’s
and 1860’s, but I doubt if any were made earlier than that,
because the circular saw did not become popular until the
1830’s, and even then it was very crude and inefficient. Almost
all the blades were made the same as the sawmill blade. They were
of a very thin gauge, and were attached to a tapered plate which
was about half the diameter of the blade. This plate came to
practically a knife edge around the outside, and its center varied
from a half-inch to several inches. This plate performed three very
important functions.

First, it strengthened the thin blade, and helped to keep it
sawing with the grain and from sawing around knots. Second, it
acted as a flywheel, keeping up the momentum of the saw as it cut
through the block, allowing faster feeds to be used, and to be run
with less horsepower. Third, as the shingle was sawn, the plate
separated or spread it from the block and saw, preventing any
binding or pinching which may otherwise occur.

The blades for shingle mills were usually about nine gauge and
ranged from 24′ to 42′ in diameter.

Also accompanying most shingle mills was an edger. This was
nothing more than a rotating iron plate with about five knives
fastened to it, and on a slight skew to the radius of the
plate.

In front of the plate was a narrow table that the shingle was
set on. With the shingle resting on this table, it was fed by hand
into the rotating knives, which quickly trimmed off all bark and
squared the shingle.

I hope this will be of help to GEM readers and if it is
favorably accepted, I have a lot more information on sawmills and
Orog saws that I can submit later.

Gas Engine Magazine
Gas Engine Magazine
Preserving the History of Internal Combustion Engines