Introduction to Basic Manufacturing Processes and ... - always yours

Fitting 387
1. Hand file
2. Flat file
3. Triangular file
4. Round file
5. Square file
6. Half round file
7. Knife Edge file
8. Pillar file
19.2.5.2 Scrapers
9. Needle file
Fig. 19.42 General classification of files based on shapes or cross sections
Scrapers are made up of old files and the cutting edge of scraper is hardened and
tempered. They are mainly used to scrap metal surfaces by rubbing the work surface. They
also produce a bearing surface, which has been filed or machined earlier. The scrapers are
hand cutting tools used for removing metal from surfaces in form of thin slices or flakes to
produce smooth and fine surfaces. Machined surfaces are not always perfectly true. If a very
true surface is needed, the high spots must be located and removed. It is normally done with
the help of a scraper. The scrapers are made in a variety of lengths from 100 mm upwards
and in many shapes, depending upon the type of work to be done. The following types of
scrappers according to shape are commonly classified as
(i) Flat
(ii) Hook
(iii) Triangular
Handle
Flat scrapper
(iv) Half round
Fig 19.43 shows various scraper which are
Hook scrapper
generally used for scraping job work in fitting
shop. These are discussed as under.
Triangular scrapper
19.2.5.2.1 Flat scrapers
Flat scrapers are commonly used for
removing slight irregularities on a flat surface.
Handle
Half round scrapper
Fig. 19.43 Common types of scraper