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

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