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| Because of the Patent Office fire in December 1836, there are no patent drawings or specification available for this patent, which is unfortunate because it is the earliest American bandsaw patent.From "Niles' Register" of 1819-03-27."The Belt Saw.—The editor of the Register was invited a few days since, to see the newly invented Belt or Strap saw, in operation; and, although very little acquainted with machinery in general, he could not help believing that a great desideratum was obtained by this application of power."The chief objections to the common upright saw, worked by a crank, we are told, are as follows: say that it makes 100 strokes per minute, of from 18 to 24 inches long—the log is pushed to the saw by means of a feed-arm acting upon a rag-wheel, put in motion by the return-stroke of the saw-gate. If the log is large, it requires but little feed; the ratchet is then often missed, and the saw does nothing, or next to nothing, a major part of the time; and that the teeth of this saw are much more injured by the up stroke, than be the cutting or down stroke, by reason of the saw dust, sand, &c. that remains in the cut of the log, the upper part of the tooth being oftentimes found to be rounded or rubbed off, when the lower part is very little injured. The up-stroke also has a tendency to destroy the set of the saw. It is further represented to be among the disadvantages attending such saws, in the great length required for the connecting rods, or pitmen—the carriage way being necessarily 25 feet from the crank, or else the saw will move badly and jar very much, as the dead centre of the crank is passed: to remove which defect, it is said, no method has ever yet been discovered. The best remedy for it is in extending the distance between the crank and the saw; and the cost, difficulty and extra labor required either to dig down for the purpose, or raise up the logs on a carriage way, elevated above the common surface of the adjacent earth, are well known to everybody."The Belt saw is free from all these disadvantages—as it is always revolving and always cutting at a regular rate, the log is always pressed against it in a regular manner, and the work goes on without any stoppage, jar, or impediment whatsoever. Thus, it is estimated that this saw will cut twelve times as much wood, at one sharpening, as the common mill saw. The comparative force of these saw, we are told, by be calculated thus: the saw moved by a crank may make 100 strokes, 2 feet long, per minute—of course 200 feet of saw is passed in the log in a minute—the Belt saw is 42 feet long, passing round two 7 feet wheels, or drums, at the rate of 100 revolutions in a minute, with a strong regular feed.—The difference is at once so obvious that nothing more need be said about it. Mr. French, the mill who put the saw we are speaking of, under the direction of the inventor, is willing to contract to erect a mill, if the power that is required is given to him, which shall cut 15000 feet of boards in 24 hours, with one saw; and he states his opinion that it will do this with one sharpening, unless in case of accident."We shall now describe the Belt Saw, which is very simple—It is made of one piece, and passed round two drums one above and the other below the position of the log; these drums are raised or depressed as need requires, and the saw, strained by them, moves in a strict perpendicular line before it reaches, and after it leaves the log. The machinery is so simple, that any person who has seen two wheels connected together by a common leather strap may understand it—the saw is as the strap, and it appears not to suffer the least damage by being so used."It is stated further, that the cost of erecting a mill and fixing up a saw of this kind, including all expenses (except the patent right) will not exceed that of a common double-geared saw mill."For particulars apply to the patentee, Mr. Adam Stewart, Baltimore—or Mr. R. French, millwright, Morrisville, Pennsylvania."The 1819-04-23 issue of Niles' Register carries somewhat of a rebuttal to Stewart's claim to having invented the bandsaw. In 1815 a French pamphlet entitled "Archieves des Decouvertes et des Inventions Nouvelles" gave credit for the invention of the band saw to a Monsieur Touroude. Stewart was given an opportunity to respond, and he claimed that his invention preceded M. Touroude's, that he filed his invention with the patent office prior to 1815, and "thinks that the idea was carried over to France by a French officer, to whom he shewed his invention, in a garret in London, before his coming to this country." |
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