Part 2

It was known, of course, that a band saw under stress would be inclined to gravitate to the rear. In this mill the attempt is made to prevent this and compel the saw to follow its proper path around the wheels by raising or depressing the tail end of the top wheel shaft; and in order to do this automatically a steel trolley was applied to the rear edge of the saw, closely following it, whatever its position might be; but any movement of the trolley towards the front or rear was followed by a corresponding adjustment of the tail box of the top shaft. The effect of the trolley on the edge of the saw was bad; and besides that there really was no special need of any device of the kind.

In connection with this mill there are also three other interesting features worthy of mention, as one of them in particular illustrates the method then prevailing of preventing a log from rubbing or dragging against the saw when the carriage was run back or being gigged for the next cut. At the present time an off-setting mechanism is applied to the carriage trucks, but previously a depressor, so-called, was applied to all mills substantially as shown in the Wilkin mill and others illustrated herein. That is to say, both the upper and lower saw guides were movable transversely, and the off-bearer by means of a hand lever, forced the guides back from the saw line, carrying the saw sideways away from the log, and in this manner contact with the face of the log was prevented; but it was hard on the saw.

In this mill, however, there is a new departure as shown by the application of two small friction rolls or pulleys behind the saw, in place of the usual saw guides; the idea being to force the saw out to the saw line by means of the rolls, and then when the carriage was gigged the rolls were moved back and the saw permitted to fall away from the face of the log; this feature being an imitation of the same thing embodied in the Allington mill previously built at Saginaw, but not shown herein. This arrangement, however, proved to be severe on the saws, because such short bends will crack them in a short time, and besides this the rolls made such a roar in a mill that not much else could be heard.

Next in this mill a spring was employed to maintain a sensitive automatic strain on the saw; and this, like the other special features of the mill, proved worthless, and the mill, like the Allington, went out of use and is unknown to the art now.

Now in all the preceding it is shown that Saw Mill Machinery Builders were studiously striving during all the years between 1880 and 1887, and some of them to a much later date, to produce a Band Mill for sawing logs that would do good work and as much of it as lumbermen would be satisfied with, and that, too, without so much cracking and breaking of saws. The simple fact that they were continually devising new constructions with a statement each time that now they had struck it, and the further fact that without an exception all of these were entirely abandoned and fundamentally new machines brought out at a later date, prove indubitably that all of their former efforts had failed to meet the full requirements which lumbermen expected and demanded.

The question then naturally arises, how did it come about that successful cutting band mills of a wholly different type are now universally in use? Who is the man who originated the strictly modern band mill that served as a pattern for all to follow? The following will explain it:

Aug. 23 and Sept. 13, 1887, patents were issued to D. C. Prescott, then of Marinette, Wis., for improvements in Band Saw Mills, and other patents followed shortly thereafter on further improvements.

The creation of these mills was purely upon the principle previously described by Mr. Esplin who so signally failed in its application. Plainly it was evident that to secure a nervous, sensitive and constant strain on a band saw, it was imperative to reduce the weight upon the straining levers to the least possible quantity consistent with strength, and to make all the pivotal points as near frictionless as possible by the intervention of knife edges or ball bearings; and while it was impossible to reduce the weight to a point so as to accomplish an automatic adjustment as quick as a flash, it is a fact, nevertheless, that in the Prescott mills of that date a strain was automatically maintained sufficient to successfully accomplish the work of sawing lumber accurately and in acceptable quantities. And these were the mills that set the pace for all other builders and revolutionized saw mill constructions.

The light metallic top wheel with its shaft, runs in boxes mounted on plungers, and from them stems lead down to the straining levers, and all were made as light as possible. Characteristically about all band mills now employ this system, and whether they have a single column or a double column, the arrangement is substantially the same.

We often read of big day’s work performed by some make of band mill, but it is proper to say that the day’s work performed in the saw mill of the North Wisconsin Lumber Co. at Hayward, Wis., has never been equaled. This was done by two of Prescott’s No. 3 mills, being the second one illustrated, as follows:

NORTH WISCONSIN LUMBER COMPANY

Hayward, Wis., Aug. 23, 1893.

D. CLINT PRESCOTT.

Dear Sir:—The North Wisconsin Lumber Company made the following cut: August 22, 1893, with two Prescott Band Mills only, 609 selected logs, scaled full. Average 1.97 to 1,000 feet, 309,400 feet.

Lumber scale, 1 inch, 45,236 1¼ and 2 inch, 294,077 ------- 339,313 feet

The cut of August 22nd shows what can be done with large logs, and the cutting was as perfectly done as any day’s cut we ever made. W. H. Elliott, Superintendent of Valley Lumber Co., Eau Claire, and A. L. Ulrich, of Rice Lake Lumber Co., will vouch for the cut of August 22nd, as well as Captain Rogers, our Superintendent, and myself.

Yours truly, R. L. McCORMICK, Secretary N. W. L. Co.

It is of interest to note the gain of about 30,000 feet by sawing the logs with a Band Mill instead of a Circular Mill.

This record, widely published at the time, coupled with the fact that nearly three hundred Prescott mills were then in successful service, is evidence enough to show that all other Band Mills as herein shown had become obsolete and were back numbers, and were abandoned for the later constructions all are now familiar with.

But before any of them, or any of the others that have appeared on the market since then, can boast of big cuts or a superior grade of mills, it is up to them to show a better record than the one above given; a record that will be vouched for by Mr. McCormick who is still alive.

There are also two of this same type of Band Mills now running in the saw mill of the Fosburgh Lumber Co. at Norfolk, Va., and notwithstanding they are nearly twenty years old, there are no Bands on the Atlantic seaboard anywhere that equal them today, either in the quality or extent of daily output.

The short, compact mill with the base above the overlays of the saw floor, originated with Prescott. Wood rims with rubber faces on the wheels were speedily abandoned by him, and wheels all of metal were brought into use, so that a filer in rolling tension into the saw had a clean wheel free from bunches of pitch and sawdust which stuck to the rubber faces and produced unbalanced wheels; but then everybody supposed that rubber faces were a necessity. Mr. Prescott demonstrated that the mill was vastly better without them.

The late improvements made in frame constructions merely add stability without increasing the quality or extent of the output, this being entirely dependent upon a light weight of the top wheel with its shaft and boxing in combination with a straining lever system made as frictionless and sensitive as possible; for without these good conditions no band mill will render duty of the highest grade.

Logically, then, the same principles and elements of construction have been embodied in all the splendid Band Saw Mills now built by The Prescott Company herein shown.

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.

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.

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.

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.

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.

The Prescott Vertical Band Resaw

This machine is built in three sizes, viz.:

With wheels 7 feet in diameter for 10-inch saws. ” ” 8 ” ” ” ” 12 ” ” ” ” 9 ” ” ” ” 12 ” ”

It is distinctly a machine for resawing plank, cants or timber up to 16 inches in thickness. The mill proper is provided with a surrounding base and is constructed upon the same principles as are all Prescott Log Band Mills. The feed works being driven by the machine itself makes the whole self-contained. The outside pressure rolls, are adjusted by power; and the inside rolls are operated by hand levers and notched quadrants, and regulate all thicknesses of lumber to 1-32 of an inch. And all of these rolls are power driven. All gearing is steel, the upper guide is power operated, and the mill itself is made self-centering when desired, although this feature is not specially necessary in this machine.

No finer machine exists for resawing lumber and timber coming from a log Band Mill or a Circular.

It is not adapted for resawing slabs.

Standard Prescott Horizontal Band Resaw Mill

For Resawing Slabs and Planks

The machine shown upon the opposite page has wheels 6 feet in diameter, and admits upon the feed rollers a slab nearly 30 inches wide and about 12 inches high, so that half logs of considerable size may be sawed as well as slabs.

Numerous feed rollers are employed instead of the endless platen or apron, thus insuring efficiency and durability.

The feed rollers are mounted upon an independent frame which can be withdrawn when necessary for purposes of repair. This is adjustable vertically by means of a hand lever with quadrant for setting the machine to saw lumber into the required thicknesses.

The base and frame are heavy and substantial, and the machinery is located above where it is accessible and out of the way of the dirt which may accumulate. A very sensitive saw straining mechanism is applied.

The pressure sprockets are supplied with power for such material as may require it, and is omitted, however, when it appears unnecessary. The feed can be increased, diminished or reversed.

The machine is located upon beams on the line of the overlays, requiring no special substructure to support it.

Other sizes are supplied for special uses and further information will gladly be given by correspondence.

The Prescott Company

Manufacturers of

Strictly Modern Saw Mill Machinery of standard sizes for medium logs and a heavy class for the large logs of the Pacific Coast or elsewhere comprising:

Band Mills for logs and resawing purposes,

Circular Mills,

Carriages, both Rack and Pinion and Screw Setting

Steam Setting and Steam Receding Machines,

Edgers—3 types

Trimmers—3 types

Log Stops and Loaders,

Slashers,

Lath Mills,

Live Rolls,

Transfers,

Log Jackers,

Steam Niggers,

Log Turners,

Kickers,

Dogs,

Rift Sawing Machines,

Steam Jump and Swing Saws,

Offsetts, etc., etc.

And a full line of Transmission Machinery all built for either Wood or Steel Construction.

PLANS OF SAW MILLS WITH SPECIFICATIONS AND ESTIMATES FURNISHED.

SEND FOR CATALOGUES

BRANCH OFFICES _Chicago, Ill._ _Seattle, Wash._ _New York_

CALIFORNIA AGENTS _The Eby Machinery Co._ _San Francisco_

Transcriber’s Notes

Punctuation and spelling were made consistent when a predominant preference was found in this book; otherwise they were not changed.

Simple typographical errors were corrected; occasional unbalanced quotation marks retained.

Ambiguous hyphens at the ends of lines were retained; occurrences of inconsistent hyphenation have not been changed.

Page 20: “slack slide” was printed that way.