GOI #2 Weapon Polishing Paste

GOI #2 Weapon Polishing Paste

GOI paste (from State Optical Institute) - grinding and polishing pastes based on chromium (III) oxide, used for grinding and polishing steel alloys, including thermally hardened, non-ferrous metals, hard plastics and polymers, glass (including optical glass), ceramic materials and products made of them.

GOI pastes were created in 1931–1933 by a group of Soviet scientists and employees of the State Optical Institute - I.V. Grebenshchikov, T.N. Krylova, V.P. Lavrov, S.V. Nesmelov.

GOI pastes varieties and their application:

There are distinguished four GOI paste numbers depending on the abrasive particles size, according to TU 6-18-36-85:

№1 (1 (black paste with a green sheen; abrasive ability 0.3–0.1 µm) for fine polishing, gives the treated surface a clean specular gloss. Composition: 65-70 parts of trivalent chromium oxide, 1.8 - silica gel, 10 - stearin, 10 - split fat, 2 - kerosene, 0.2 - two-carbonic (drinking) soda;

№2 (dark green paste; abrasive ability of 7—1 microns) for fine polishing, gives the treated surface a specular gloss. Composition: 65-74 parts of trivalent chromium oxide, 1 - silica gel, 10 - stearin, 10 - split fat, 2 - kerosene, 2 - oleic acid, 0.2 - bicarbonate soda;

№3 (3 (green paste; abrasive ability of 17–8 microns) for medium grinding, gives a clean surface without strokes and is used to achieve an even polished surface gloss. Ingredients: 70-80 parts of trivalent chromium oxide, 2 - silica gel, 10 - stearin, 10 - split fat, 2 - kerosene;

№4 (light green paste; abrasive capacity of 40-18 microns) for rough grinding, gives a matte surface and is used to remove the smallest scratches left on the surface after grinding with abrasives. Ingredients: 75-85 parts of trivalent chromium oxide, 2 - silica gel, 10 - stearin, 5 - split fat, 2 - kerosene.

The abrasive GOI paste ability is determined by the metal thickness removed from the steel plate 9 x 35 mm when it passes 40 m path along the cast iron plate 400 x 400 mm [5].