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Carl Peterson No-Commission Sawmill Excha
Sawmill Comparisons Disclaimer:
This page has been prepared by myself, Carl Peterson, the inventor
of the original Peterson Portable Swingblade Sawmill. Although I may bring
an informed bias towards these comparisons, I have taken great pains to
present the true and relevent facts as I see and understand them. I have been
involved in the portable milling industry longer than most, and take
some pride that the entire swing-blade revolution emitted from my own
backyard. During the 29 years since I first envisioned the swingblade
concept, I have studied every possible avenue of portable sawmilling. I
have used the felling axe, drowned in my own sweat and sawdust while pit-sawing,
struggled with chainsaw slabbing, tried Pacific bench sawing,
twin-saw operation, and use of bandsaw mills. I have sawed in the
USA, Canada, Fiji, Solomon Islands, Vanuatu, Papua New Guinea, Australia, and
New Zealand, encountering just about every possible type of timber.
Consequently, there is probably no one alive better qualified to advise and
critique the various milling technologies. I believe I have been gracious and
fair in my evaluations. I invite you to share the knowlege I have gained from
all these experiences. With this information, you can easily compare the strengths of band saw mills, double bladed sawmills ("quarter saws"), circle mills, and swing-blade sawmills against the requirements of your specific situation. If you feel I have included any annoying errors of
fact, I invite you to email me at webmaster@truthaboutax.com so it can
be made right.
Comparisons-
Circular (Single) Blade Sawmills
This type of sawmill has been around for ages. They work, and work well,
provided they are set up properly, the blade is properly tensioned and
sharpened, and a skilled sawyer is at the helm. With this concept, the log is
usually made to pass through the permanently fixed-position blade. The
downside is that they take out a considerable kerf as sawdust, usually running
at around 3/8". As well, they usually require an extensive permanent site, and
at least some ancillary equipment such as an edger saw to make them
competively productive. Recovery rates for commercially operated circular saws
usually range between 40%-55%, with only the latest state-of-art computerized
circular sawmills achieving anything close to that 55% mark. The more aged
circulars on the market also seem to be famous for cutting boards with a lot
of thickness variations, often plus or minus 3/8". In today's competitive
market, it just doesn't make sense to buy an old circular mill, spend a whole
lot of time setting it up on your site, and expecting to make a lot of money
with it. On the other hand, if used solely for your own requirements, running
one of these "oldies" can be a fun and enjoyable experience, and
reasonable quality timber can be made to fill your own requirements. The Frick
mill is included in this category.
There are a few modern versions that are mounted upon easily moveable
trailers. These mills can be effective cutting high volumes of small-sized
logs. Unfortunately, they tend to be very expensive, requiring the
edger/resaw equipment to be built in-line with the major breaking-down saw.
The Kara mill is one such example.
Comparisons-
Twin Blade (Double Bladed) Sawmills
The twin blade concept came into being in the mid 1950s and has been
around ever since. There are a great many different variations using these two
blades, which are set at 90 degree variance to each other. With these mills,
the cutting blades are usually mobile, passing through a stationary log. A
single (or double) board can be cut and removed with each pass down and back
upon the log. This concept allows smaller and more stable blades to be used,
usually allowing the saw kerf to be reduced to between 1/4" and 3/8". These
mills tend to be reasonably heavy, requiring a robust trailering base as a
mounting foundation. Major advantages of this type of mill are the ability
to saw very large logs with moderate horsepower (often between 20-60 hp) and
in automated versions the ability to return the sawn timber or flitches back
to the operator.
Recovery rates with these mills can usually average between 50%-60%. And
because they make at least two cuts at a time, edgers and resaw equipment are
not required.
The downside is, these mills struggle when cutting smaller logs. The
double blades have been known to toss small logs that are not well anchored a
fair distance, even causing severe injury on occassion. They also struggle
hugely when sawing timbers with high tension. In such cases, it is almost
impossible to saw accurate dimensions with this type of mill. Because recovery
rates are not competive with swing saws or bandsaws, the twinblade saw
should be considered when sawing logs over 20" in diameter, cutting
mostly 2" stock and greater, and while cutting logs of generally lower value
wood. Examples of twin-saw sawmills include Mighty Mite, Mobile
Dimension, Mahoe, Forestmill, and Rimu.
Comparisons-
Bandsaw Blade Sawmills
There are scores of bandsaw manufactureres around the world. The bandsaw
has found application in every thing from cutting hobby wood in the home
workshop to breaking down large logs in multi-million dollar timber processing
plants. Bandsaws are at their best in very specific situations. Because
of their extremely small kerf, they are ideal for resawing flitches and
cants into finished boards. For this purpose, they are unsurpassed by any
other practical technology. The market in bandsaws designed for
reducing whole logs has profligerated on the back of a whole lot of hype and
propaganda regarding the extremely narrow saw kerf and the increased
recovery rates theoroetically possible.
Unfortunately, when designed to cut whole logs in a portable operation,
a lot of compromises need to be made with this technology. Firstly, the bandmills
have to be designed to cut logs up to around 30 inches in diameter. Otherwise
they miss out on a great deal of the portable milling market. And when
cutting those large logs, the technology struggles to provide accurate and
straight cuts. Unless the band blades are immaculately sharp and
perfectly tensioned, those large cuts tend to wander somewhat through the cut.
Unless the logs are debarked before sawing, the bark, sand, dirt, grit, and
small stones lodged therein quickly dull the blade and lead to even more
deformed sawn timbers. And of course, whenever the band blade
gets dull, it wanders all over the place. You throw that wavey board away, put
on a freshly sharpened band, cut another board, and throw that one
away, too.
In most portable sawmilling situations, the bandsaws just do not
cut it for accuracy, recovery, ease of use, or speed of cut. You have to be an
expert sawyer to make it work at all, bandsaws are almost always slow
compared to equally priced swingers, they tend to waste a lot of boards
due to wavey cuts, they have difficulty cutting stressed timbers (again, a lot
of wasted boards), they struggle on large logs, and they require an awful lot
of double handling in resawing slabs or edging boards. And on top of all that,
most serious bandsaw operators spend a couple of hours per sawing day
just resharpening and readying the band blades for the next day's
sawing.
Don't get me wrong. There is a lot of great technology employed in the
more expensive, automated band sawmills. The point is, it's often the
wrong technology for sawing logs into dimensional timbers. It's therefore
overly expensive, relatively unproductive, labor intensive, and is simply the
wrong application. Now, some of these problems can be minimized by sticking to
smaller logs, debarking the logs (a lot of work), and adding an edger
(expensive) to the operation. But my back is already hurting just talking
about it!
On the plus side, most portable bandsaws can be used effectively and
efficiently as efficient and practical re-saw machines. That is, use them for
resawing cants and flitches into thinner stock boards, rather than trying to
reduce large, whole logs into finished boards.
Examples of popular portable bandsaws include Woodmizor, Baker,
Timberking, Cookes, Norwood, MSG, Timber Harvester, and Hud-son.
Comparisons-
Swing-Blade Sawmills
The "swingers" have really taken the portable sawmill
market by storm. Time and time again they have shown at portable sawmill
shootouts, through Lucas and Peterson, to be able to
out-gun other mills costing two or three times as much. In most versions
highly portable, they have also been able to merge great cutting speed,
consistent accuracy, with very high recovery rates; usually surpassing bandsaws
in recovery in practical field situations. The swing blade saw kerf is
usually well under 1/4", with some special applications possible using just
over 1/8" kerf. But the secret here is not in the thin kerf.
The real secret lies in the consistent accuracy and consistent sizing
achievable. The relatively smaller swing blades distort less than
larger circular blades, and are more stable in the cut. And because
they have the entire motor horsepower focused on a single cut in each
direction, they effectively cut twice as fast as an equivalent twin saw
system laboring through two cuts simultaneously.
Swing saw blades are cheap and easy to maintain. They can be
sharpened on the mill in less than a minute or two, sharpened perhaps a
hundred times before being retoothed, and require only a couple of sharpenings
per day. Obviously, a sharp blade will cut faster than a dull one, but
at least on a swinger a dull blade will still cut accurate timbers. In
the final analysis, the blade maintenance costs on swingers are
only about 1/10the the cost of bandsaw blade maintenance.
Another advantage of the swingblade mill is the ability to "double
cut" with the horizontal positioned circular blade.
With the Peterson mill this is easily effected by first sawing on the
left side of the log with the right side of the blade, sliding the
carriage to the right, and by then sawing on the right side of the log with
the left side of the blade. With the Lucas, the carriage is
lifted and rotated 180 degrees to achieve a similar end. Both the Lucas
and the Peterson "ATS" are at their best sawing logs larger
than 20" in diameter. The Peterson "WPF" is equally at
home with either small or larger logs, and also boasts a single rise and fall
mechanism.
Lucas swingblade mill has been around in the USA longer than Peterson.
The Lucas mill began as an early Peterson-type mill with the
addition of two rise and fall winches. It has become a slick outfit, well
marketed and supported by Baily's, and generally well presented when
new. There are probably five times more Lucas mills in America than Petersons.
Second hand Lucas's are far more abundant, and can often be had at a
bargain. A good Lucas mill can achieve awsome production on large logs
equalling the Peterson, and in most configurations is at least slightly
less expensive. On the down side, cheaper materials are used, the machine is
more prone to rusting, Lucas blades are more vulnerable to heating and
distortion, and the Lucas is generally made for earlier consignment to
the scrap heap. From an operator's point of view, there is a lot of walking
required, as the winches are located at oppositie ends of the tracks. When
used by a single operator, double cutting becomes all but impossible,
or at least impractical, as the carriage must be completely turned around. As
well, the tracks become dangerously skewed when dropping down one end at a
time.
Petersons sawmills boast a lot of precious metal in the
construction, being predominantly stainless steel and aluminum. The Peterson
blade locking mechanism is reportedly easier to use, more operator friendly,
and more reliable than the Lucas gas strut. Double cutting,
difficult with the Lucas, is extremely easy to effect on the Peterson.
Peterson also makes a 10" cut version, an automated version (the "ASM"),
and a small electric version called the "Skillmill" costing
only US $3900.
The Peterson "ATS" (all terrain sawmill) uses two
winches at one end, saving boot leather and time walking back and forth, and
making accurate sizing easier. The "ATS" does not have the
constraining top cross member that the Lucas has, which limits the log
length ability on large diameter logs.
The Peterson "WPF" is equally at home cutting large or
small logs, being transported between sites or in fixed site arrangement, and
in cutting short logs or very long logs up to 60 feet long. The "WPF"
is Peterson's most popular commercial-grade mill. Although
significantly more expensive than either the Lucas, or the Peterson
"ATS", the "WPF" mill offers better
functionality, more flexibility, easier access for operator and log, and
improved accuracy. An electric rise and fall option adds to operator
convenience.
If you are a new mill buyer hoping to earn a reasonable commercial
income, the "swinger" is definitely the way to go!
And why settle for second best when you can buy a brand new
Peterson Portable Sawmill for just a little more?
Disclaimer:
The views and opinions expressed here and
elsewhere on this site are those held by Carl Peterson personally, and are not
to be construed as representing the views of Peterson Global Sales, or any
other employee involved in the manufacture or sale of the present Peterson
portable sawmills.
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