Of this type The Prescott Company builds the following sizes, both
right and left hand, single or double cutting:
Diameter of wheels 7 feet for saws 10 inches wide.
” ” ” 8 ” ” ” 12 or 14 inches wide.
” ” ” 9 ” ” ” 12 to 16 ” ”
Next is shown the Pacific type of the Prescott Band Saw Mills for
cutting large logs, having wheels 9 feet in diameter, and using saws
from 12 to 16 inches wide. They are built for double cutting as shown,
as well as for single cutting. Their dimensions are about as follows:
Base 9′ 7″ by 11′ 7″.
Maximum distance between guides 6′ 6″.
Distance from saw line to column 4′ 6″.
Maximum length of saw 53′ 6″.
Weight from 42,000 to 45,000 lbs.
When desired a steam cylinder is applied for operating the upper guide,
and a reversing engine for adjusting the top wheel when changing saws.
Their straining mechanism is exceedingly sensitive, their shafts are
large, their boxes 18 inches long and water cooled; so that in every
respect these mills are perfectly equipped, and a 20-inch double belt
is necessary to drive them.
* * * * *
For the largest logs of the Pacific coast cut with a Band Saw Mill, The
Prescott Company advanced to a mill of the same type but having wheels
10 feet in diameter for saws up to 18 inches in width.
The base of this mill is 10′ 7″ by 14′ 6″.
Maximum distance between guides 7′ 3″.
Maximum length of saw 60′ 9″.
Distance from saw line to column 5′.
Weight from 54,000 to 58,000 lbs.
The shafts are large with 20″ water cooled boxes. Steam is applied to
operate the top guides and adjust the top shaft when desired. A 24-inch
double belt is necessary to drive it.
[Illustration: PACIFIC COAST, 9 FOOT SINGLE AND DOUBLE CUTTING BAND
MILL]
[Illustration: PACIFIC COAST, 10 FOOT BAND MILL]
In every respect these mills are splendid creations and exhibit a vast
stride in advance of the earlier mills described herein.
All of these mills are provided with a surrounding base, a powered
upper guide, quick opening lower guide (as shown on page 45), live
roller, means for maintaining alignments and adjusting the upper wheel
when changing saws, the latter being done either by hand or power as
required; and the upper wheel in all of these mills when raised to the
maximum point admit of the use of a long saw for sawing occasional
large logs, a saw two feet shorter being in use normally for medium
sizes of logs which are mostly cut. And these mills in combination with
a Prescott carriage constitute an equipment absolutely unrivaled by any
other productions in the world.
Rack and pinion head blocks, every piece of which is an open hearth
steel casting, are furnished in sizes varying from 36 inches to 72
inches, being the distance the knees recede from the saw line; and
these with frames proportionate in dimensions and composed of well
seasoned southern pine timber, well ironed and braced, comprise great
strength and durability.
For mechanically exact setting, all racks, pinions, taper sets and
ratchet wheels are cut from solid blanks in a gear cutter. The knees
are operated either by hand lever and quadrant, the familiar way, or by
a Prescott Steam Setting Machine, which advances them for 4-inch lumber
or any thickness less, varying by 1-64th of an inch to every click of
a pawl on the ratchet wheel, and that too with a single rearward and
return stroke of the piston, so that great speed and accuracy are the
characteristics of this machine; and with it an increase of cut is
obtained by reason of the fact that the setter does not get tired, and
no sawyer will have to wait for him. And more, with them a mill man can
keep a good setter who otherwise might be on the hunt for an easier job.
These carriages are also supplied with Friction, Spring or Steam
Receders, which latter can be employed in all cases where Steam Sets
are used for which steam is delivered to the moving carriage. The value
of steam receders consists in the ability to advance or recede the
knees at any time whether the carriage is moving or at rest, and for
receding the knees of large blocks sawing short logs only.
[Illustration: Standard 3-Block Carriage with 4-inch combined steam and
ratchet set works]
A Revolving or Flat Scale always indicates the position of the knees.
Dogs hold the logs. An Automatic Offset gives a clearance of the saw
when on the gigg, and Steel Trucks and Steel Track necessarily go with
such a carriage, composed either of heavy T Rail, or the lighter rolled
track, according to the size and weight of the carriage.
For accuracy and speed these carriages have no equal, especially when
handled by a Prescott Direct-acting Steam Feed.
[Illustration: PACIFIC COAST SCREW BLOCKS]
Both the knees and bases of these blocks are composed of solid open
hearth steel castings faced with heavy steel bars, presenting wide
surfaces for the knees which are grooved to fit them. The knees are
supplied with rolls, spud and extension hook dogs. The screws are
4-inch pitch and triple threaded. The gears are steel and cut in a gear
cutter and are actuated in setting by hand levers and quadrant or by
power in accordance with the wishes of a purchaser.
The Prescott Company furnishes these blocks in the following sizes,
viz.: 72-inch, 84-inch and 96-inch; being the distance the knees recede
from the saw line.
And in all other respects the equipment of the carriage is very heavy
and fully up to date in every respect.
[Illustration: QUICK OPENING LOWER GUIDE]
These Guides are applied to all Log Band Saw Mills built by The
Prescott Company. When slivers, bark or sawdust wedge in the Guide and
cause trouble and heat the saw, then the Guide is promptly opened by
the off-bearer and the stuff falls through.
When changing saws the Guide can be promptly opened.
[Illustration: VERTICAL BAND RESAW