Page 78 - CITS - Fitter Trade Pactical - Volume - 2
P. 78

FITTER - CITS

           Sharpening half round scrapers

           Objectives: At the end of this exercise you shall be able to
           •  sharpen a half round scraper.



           Scrapers are usually re-sharpened on oilstones. When cutting edges are badly damaged, they are ground on
           pedestal grinders.
           Sharpening half round scrapers
           Half round scrapers have two cutting edges on the rounded back. (Fig 1)

           The cutting edges are formed by the bottom surface, and the flat surfaces are ground on the rounded back of the
           scraper. (Fig 2)

             Fig 1                                               Fig 2














           Grind the bottom surfaces with a slight curve. This helps the cutting edges to make point contact on the surfaces
           being scraped. (Fig 3)
           Rub the bottom surface with a rocking motion on the oli stone for re-sharpening. (Fig 4)

             Fig 3                                             Fig 4










           When the cutting edge is blunt it can be re-sharpened by grinding the bottom surface.

              Note: As far as possible avoid grinding of the edges. (Flat surface ground on the rounded back)






























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                                            CITS : CG & M - Fitter - Exercise 21
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