Page 77 - CITS - Fitter Trade Pactical - Volume - 2
P. 77

FITTER - CITS



           Move the scraper in an arc to provide a slightly concave surface on the cutting edge. (Fig 3)

             Fig 3










              Note: If the scraper is carbide-tipped use silicon carbide or diamond wheels. (Fig 4)
           The cutting edges sharpened by grinding should be honed. Honing removes grinding marks and provides keen
           cutting edges.
           Use a fine grade aluminium oxide oilstone for honing. While honing use a lubricant.
           Mix light mineral oil with kerosene for preparing the lubricant.

           Hone the faces first with a movement as shown in Fig 5.
             Fig 4                                         Fig 5














           Then hone the cutting end by placing the scraper in an upright position on the oilstone with a rocking movement.
           (Figs 6 & 7)

              Fig 6                                        Fig 7



















           What should be the cutting angle? It should be
              -  for rough scraping - 60°

              -  for final scraping - 90°












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                                            CITS : CG & M - Fitter - Exercise 21
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