Scraping tool

“ It is a steel rod, having a round eye at one end, through which a round wooden handle passes. At the other end is a spiral twist terminating in a conical screw with a sharp point. The edge of the spiral is a nicker which cuts the grain of the wood around the edge of the hollow.
Fig. 112.—Handled Steel Scraper.
Abrading and Scraping Tools.
Steel Scrapers.—The scraper is a thin and very hard steel plate, approximately 5 in. by 3 in., with or without a handle (see Fig. 112) . Its action is really that of a cutting tool. It is used on a surface previously
Fig. ”

“ All of the important alignments in milling machines are obtained by scraping, a process consisting of going over the different bearing surfaces by hand with a chisel-like tool, and removing the highest spots until a maximum number of bearing points is secured. ”

“ With the fine feed and quick speed the pores of the iron do not show; with a coarse feed the pores show very plainly and are exposed for quite a depth.
After the lathe-tool comes a well oil-stoned hand-scraper, with a piece of leather between it and the tool rest to prevent the scraper from chattering. The scraper not only smooths the surface, but it cuts without opening the pores. It is used at a quick speed, as quick indeed as it will stand, which varies with the hardness of the metal, but is always greater than is possible with a slide-rest tool. ”

“ The “end-scraper on a blade” is a tool with one or both ends worked so as to give a good scraping edge. It could have been used to hollow out wood or bone, scrape hides, remove bark from trees, and a number of other things (p. 78) .
There is one very special type of flint tool, which is best known from western Europe in an industry called the Solutrean. These tools were usually made of blades, but the best78 examples are so carefully worked on both sides (bifacially) that it is impossible to see the original blade. This tool is
7. ”

“ CI, fig 2.
Scrapers have also been found in both hemispheres and in all ages. There are the same differences in material, form, and appearance as in the polished stone hatchet. There is one difference to be mentioned of this utensil—i. e., in America the scraper has been sometimes made with a stem and with notches near the base, after the manner of arrow- [Pg 979] and spear-heads, evidently intended to aid, as in the arrow- and spear-head, in fastening the tool in its handle. This peculiarity is not found in Europe, or, if found, is extremely rare. ”

“ When a scraper becomes dull (1) each edge is drawfiled, Fig. 121, so as to make it square and straight, with the corners slightly rounded. Sometimes the edges are rounded slightly from end to end to prevent digging. [73] Frequently the scraper has its edges and surfaces ground square on an oilstone after the drawfiling that the arrises may be formed into smoother burs. (2) After filing, the scraper is laid flat on the bench and the arrises forced over as in Fig. 122. The tool used is called a burnisher; any smooth piece of steel would do. ”

“ The end scrapers are divisible into three categories. The first form is a flat scraper, generally triangular to oval in outline. The working end is often thin. There are a few true snub-nosed scrapers in this category. The second type is generally fan-shaped with a wide thin bit. The opposite end usually tapers to a sharp edge which could have had secondary use as a cutting tool. The third variety includes rougher forms, though there are a few well made specimens. All have a distinct keel. There are 31 of the first type, the smallest 1⁄2 × 7/16; the largest 11⁄4 × 11⁄2 inches. ”

“ Fig. 85 shows a scraper for water mains, similar to Appold’s but modified in details, as constructed by the Glenfield Company, at Kilmarnock. A is a longitudinal section of the pipe, showing the scraper in place; B is an end view of the plungers, and C, D sections of the boxes placed at intervals on the main for introducing or withdrawing the scraper. The apparatus consists of two plungers, packed with leather so as to fit the main pretty closely. On the spindle of these plungers are fixed eight steel scraping blades, with curved scraping edges fitting the surface of the main. ”

“ Suitable flakes and chips were no doubt also carried off to be turned to account for scrapers, knives, and other small implements. Partially shaped disks and other pieces of all sizes abound in the pits, but the finer manipulation, by means of which small arrow heads, lances, drills, scrapers, etc., were fashioned, was reserved for leisure hours at home, and for the patient labour of the skilled tool-maker, for whose use the raw material was chiefly quarried. ”

“ It would appear that scraping might be more quickly done by taking long scraper strokes promiscuously over the work, but in this case the bearing marks are not well defined and do not show plainly, which leads to confusion and causes indecision as to where the most or heaviest scraping requires to be done, whereas in the block scraping the marks are clearly defined and the high patches or spots on the work show very plainly, and the workman is able to proceed intelligently and with precision. ”

“ It is a good rule that files and rasps are to be used on wood only as a last resort, when no cutting tool will serve. Great care must be taken to file flat, not letting the tool rock. It is better to file only on the forward stroke, for that is the way the teeth are made to cut, and a flatter surface is more likely to be obtained.
Both files and rasps can be cleaned with a file-card, Fig. 148. They are sometimes sharpened with a sandblast, but ordinarily when dull are discarded.
Scrapers are thin, flat pieces of steel. ”

“ Of at least equal importance with the lead screw and work and their relationship to each other is the tool-support with its screw-adjusted cross-slide (fig. 2) . Just how this was attached to the frame of the machine so that it placed the tool at a suitable radius is again a questionable point. The very well-developed cutting tool is sharpened to a thin, keen edge totally unsuited for cutting metal but ideal for use on a softer, fibrous substance: undoubtedly wood, in this instance. ”

“ Nippers (Fig. 74) are made to cut wire, but not to pull nails. Being tempered for cutting, those of good quality are hard and brittle, [Pg 96] lacking the toughness necessary to pull nails, for which work a cheap pair of nippers may be purchased.
55. The scraper is one of the most useful tools in the kit of the carpenter who works upon hard wood. This tool may be purchased, or made of a very hard saw; it must be of hard, tough steel, or the edge will not last. A scraper should be about 3” × 5”, which is a convenient size for grasping with the hand. ”

“ The alternate spaces between the lines were then cut out with a chisel and hammer and smoothed by filing. A block of lead and tin, as a temporary guide nut, was then cast around the partially formed screw. Adjustable cutters were fixed upon this guide nut and it was used as a kind of tool-holding slide-rest, being rotated around the screw by hand levers, thereby cutting the finished thread. In other words, a lead screw was cut on the piece itself and the temporary nut was used as a tool holder to finish the work. ”

“ When the hole becomes deep, it should be cleared out with a scraper during the time of changing the bit, and in very [148] argillaceous rock it may become necessary sometimes to withdraw the tool, and to remove the accumulation with the scraper. When the débris does not work out freely, its escape may be facilitated by giving a slow motion to the tool, and then suddenly changing to a rapid motion. When several machines are employed, the maximum number that can be applied with advantage is one to the square yard of working face. ”

“ It is obvious, however, that there is no front rake to the tool, and that it therefore derives its keenness from the amount of side rake, which may be regulated to suit the conditions.
When tool holders of this class are employed, the end face only of the tool requires grinding to resharpen the cutting edges; hence the area of metal requiring to be ground is much less than that on forged tools, and therefore the grinding occupies less time; and if the workman grinds the tools, he is enabled to run more lathes and not keep them idle so long while grinding the tool. ”

“ The positions in which to hold cutting tools while grinding them are as follows: The bottom faces of lathe tools and the end faces of tools such as scrapers should be ground with the tool laid upon the grindstone rest as in Fig. 2064, the stone running in the direction of the arrow. The best position for thin work as blades is at f providing the stone runs true, for otherwise the tool edge will be liable to catch in the stone. ”

“ A less costly and cumbersome machine consists of a revolving brush mounted obliquely, which sweeps a track 6 ft. wide and leaves the dust or mud on one side to be gathered up by hand. A horse scraping-machine which delivers the mud at the side is also used, the blades of the scrapers being mounted obliquely and covering a width of 6 ft. For general use, more especially in the country, scraping-machines, worked by a man from side to side of the road, and scraping a width of about 4 ft., are more convenient. ”

“ Whether one or two set-screws are used, the boring tool may be forged from a single bar of octagon steel, which can be seated in a piece like that shown at e in Fig. 610, which is grooved so as to receive and hold the tool. As is well known, boring tools are the most troublesome both to forge and to adjust in the lathe, and, as the result, a light tool is often used because no other is at hand and it is costly to make a new one. ”

“ We now come to the most difficult operation in turning, that of cutting a screw; to perform it well and easily is a proof of the workman’s skill and proficiency in the art. There are many ways of doing it; we shall therefore give the best and least expensive. The screw tools, figures 14 and 15, plate 1, must fit exactly one into the other. Fig. 15 is an outside, Fig. 14 an inside tool. As the threads may be required to be cut coarse or fine, according to the work you are engaged upon, the small grooves in the tools are made to suit. ”

“ A lead screw should preferably be as near as possible to the middle of the lathe shears, and as close to the surface as possible, so as to bring it as nearly in line with the strain on the tool as possible, but on account of the cuttings, which falling upon the screw would cause it to wear rapidly, it is usual to locate it on one side, so as to protect it from the cuttings. ”

“ As the student must in any case learn how to sharpen his tools, it will be just as well to get them in that way rather than ready for use. As this process of sharpening tools is a very important one, it must be reserved for another place. Should tools be seriously blunted or broken they must be reground. This can be done by the carver, either on a grindstone or a piece of gritty York stone, care being taken to repeat the original bevel; or they may be sent to a tool [41] shop where they are in the habit of grinding carving tools. ”

“ There are a variety of mechanical scrapers on the market, and the output of goods per hour is perhaps the guide in selecting a scraper for a large output. All things considered, a vertical type barrel equipment, with scraping arms, delivering the hog into a horizontal beater type would appear as the most efficient and the less expensive for up-keep. ”

“ The workman never left his machine. He was provided with a number of tools, set in compartments in a box. When a tool became dull he took it out, set it in the box upside down, and substituted another. A boy went regularly through the shop, took up all the upside-down tools, ground them, and brought them back. The grindstones were provided with tool-holders and a compound screw feed, by which the tools were always presented to the stone at the same desired angle, and were prevented from wearing out the stone by running into grooves or following soft spots. ”

“ When the flakes have been chipped into the scraper form at both ends they may be termed double-ended scrapers—to which class circular scrapers also belong; where a sort of handle has been worked they may be termed spoon-shaped, and where the butt has been chipped to a sharp chisel-edge, at right angles to the flat face, they have been called tanged scrapers. ”

“ I used the grinding process to a limited extent, merely to give surfaces, such as those of slide-rests, the regular even appearance that was generally considered to be the proper indication of truth, to which I knew it in no way contributed.
Now, however, the mottled appearance produced by the scraping instrument is recognized as an indication of truth, and is sometimes applied to surfaces which have not undergone the process of correction, and are not true. It is very satisfactory to me to find that the advantages of the system are now universally recognized. ”

“ Scraping with pieces of glass is an antiquated, clumsy method.
When scraping, the press should lie flat on the table edge, the other end being supported by the press-jack. In scraping, the blade is held in both hands, scraping away from the worker, the scraper sloping forwards. The press must be made immovable. Scraping is continued until all places have been gone over and the whole is perfectly smooth [Pg 75] and even. When this is accomplished, the edges are thinly coated with paste, which is well rubbed in along the sheets with a bundle of waste paper until the edges look as if burnished. ”

“ If ammonia or alcohol is put into the sprinkling-water, rinse the sprinkler well before putting it away.
A Tool Box: Fill cracks with putty to keep out dampness, hinge on a cover, and furnish with a padlock. Keep in it a sharp fine saw, a hatchet, tack hammer, brace and assorted bits, chisel, monkey wrench, screw-driver, and gimlets. Also assorted brads, tacks, wire nails, screw hooks, screw eyes, and picture wire. A putty knife is useful. A T-square and foot rule are indispensable. ”