Читать книгу The Handyman's Book of Tools, Materials, and Processes Employed in Woodworking - Paul N. Hasluck - Страница 143

A frequent mistake is to put too great pressure on the gouge, and to stroke too much, the burr thus produced being large, jagged, and too much bent over to enable the scraper to do its work at a comfortable inclination. Another is to give the gouge too much slant, as shown in Fig. 423, this also necessitating excessive tilting over of the scraper when at work, as indicated in Fig. 424. In resharpening, many workmen, instead of rubbing the corners square upon the oilstone, simply lay the scraper on the bench, and, as already stated, stroke it over in both directions afresh. Figs. 425 to 427 illustrate the bad effect of this. If the scraper was sharpened well in the first instance, it will, when ready for resharpening, appear like the section at K (Fig. 425). When the gouge is stroked heavily along it, the burr edge must either be closed against the side, as shown at Fig. 426, or be drawn out as at Fig. 427. If the former, then the difficulty of forming a new burr edge is very great; if the latter, then the original burr is merely bent outwards again when the gouge is applied to the edge of the scraper, and will invariably be found stripped off and broken, if the edge is examined after the scraper has been applied to the work a second time. Scrapers for special work are illustrated by Figs. 428 and 429, and there are many other shapes.

Fig. 423.—Wrong Method of Forming Burr Edge.

Fig. 424.—Using Badly Sharpened Scraper.