The Southern Yellow Pine logs were secured from a tract of land near
Groveton Texas. The logs produced from the tract are exceptional and will
produce quality timbers for the frame. Below are some pictures of the
logs and the initial milling process.
| When the logs were delivered to us the moisture content
of the log is still "forest green". We keep the logs wet
to inhibit the germination of molds and fungi until they are sawn.
One of the most common molds is called "blue stain" for
the bluish pigment the mold produces. A pile of logs, as seen here,
is called a log set. You can just see the sprinkler jet behind the
log loader in the picture. Logs are delivered to us in 33 foot lengths
and each log truck will hold about 32 tons of logs. |
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Before a log is moved to the saw mill it is "bucked"
(cut) to length and the end pieces are removed. You can see an end
piece just to the right of the log and of course the saw dust from
the chain saw. This log has yet to be bucked.
Log diameters average 12" to 14" and some even larger
depending on the frame requirements. We provide John Box, our sawyer,
with a complete list of all timbers needed for a frame so he knows
exactly what to produce.
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Here the logs have been moved to the saw mill and are ready for
the initial cuts. The mill we use is a band saw mill rather than
a circular or sash mill. Band mills produce very accurate cuts and
slight "kerf". Kerf is the amount of wood that the saw
blade removes as it works through the wood. Reducing kerf reduces
waste and produces a cleaner cut.
John will inspect each log to determine the best way to mill it
to fit a specific size and length on the saw list, then position
the log on the mill to make the first cuts.
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Here, John is making shallow passes with the saw blade
to remove the outside bark. A timber is produced by removing shallow
sections of wood at a time; reading, turning the log and making a
new cut until a four sided timber is revealed. |
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Only two sides of this log have been cut but it will soon become
a square timber as the two remaining sides are sawn. A four sided
square timber is called a "cant" but it is not yet to
cut to size.
One inch thick boards will be cut from each face of the cant until
the final sawn size is achieved. You should notice that the center,
or heart, of the tree becomes the center, or heart, of the timber.
This "boxed heart" cut equalized the forces exerted by
the individual wood fibers thus greatly reducing bowing, twisting
and warping of the final timber.
The next step for this sawn timber will be the dry kiln.
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This is an interior view of the dry kiln where you can
see some of your timbers stacked on the left. The drying process takes
28 days to fully dry the timbers to a moisture content of about 16%
to 18%. Drying the timber greatly reduces its tendency to shrink which
reduces checking (cracks along the face of the timber) and helps ensure
tight joints in the finished frame. |
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These timbers have been kiln dried. The boxed hearts are plainly
visible. You should also notice the DVS stamp on the timber ends.
DVS is the customer reference tag. That's how we keep all the timbers
separate from other projects. We cut only what we need for the frame
and a few extra timbers just in case. Each timber is meant to fit
a specific location in the frame. The next step for these timbers
is our timber sizer. The timber sizer dimensions and squares the
sawn timbers.
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