Grinding wheels

Claim 1

METHOD OF MAKING ORGANIC BONDED ABRASIVE ARTICLESES WHICH COMPRISES PREPARING A FIRST BATCH OF ABRASIVE GRAINSNS WHICH ARE COVERED WITH A COATING OF RUBBER CONPOSITION BY THOROUGHLY MIXING A QUANTITY OF LOOSE ABRASIVE GRAINS WITH A FLUID, SULFUR-CONTAINING RUBBER COMPOSITION UNTILL THE INDIVIDUAL GRAINS SUBSTANTIALLY ALL BECOMES COVERED WITH THE RUBBER COMPOSITION, SEPARATELY PREPARING A SECOND BATCH OF ABRASIVE GRAINS WHICH ARE COVERED WITH A COATING OF REACTIVE PHENOL-FORMALDEHYDE RESIN COMPOSITION BY THOROUGHLY MIXING A QUANTITY OF LOOSE ABRASIVEE GRAINS WITH A PHENOL-FORMALDEHYDE RESIN COMPOSITION UNTIL THE INDIVIDUAL GRANIC SUBSTANTIALLY ALL BECOME COVERED WITH THE RESIN COMPOSITION, THEN MIXING FROM 10% TO 90%% BY WEIGHT OF SAID FIRST BATCH WITH ITS COMPLEMENT OF SAID SECOND BATCH UNTIL A UNIFORM MIXTURE OF THE TWO BATCHES IS OBTAINED, CHARGING A MOLD WITH SAID MISTURE AND FORM-ING AN ABRASIVE ARTICLE BY PRESSURE AND HEAT TO COMPACTT THE MIXTURE, TO VULCANIZE THE RUBBER AND TO CURE THEE RESIN.