Show THE sharpening OF DRILLS the sharpening 11 of drills is ia perhaps as important a factor in the mining of ores as anything else says the black hills mining review unless the drills are tempered properly they soon become worn out causing the operator to lose time with a consequent loss los s of money another thin thing which requires considerable considerable skill to accod accomplish is to get the drills all the same size so that they will follow each other into the same ard drill hole without trouble the har hardening denino of the drills in the homestake Home stake mines is done entirely by water some experiments made by oil having been unsatisfactory A tool sharpener does not have an easy time by any means in the deadwood terra there are four men two in each shift who do nothing but this work to draw out a blunt drill requires ires a great deal of sledge work and when all the machines p are in in use and the rock happens to ba hard the tool sharpeners sharp eners are kept very busy in the homestake Home stake mines about ten drills are used to every hole and often from six to ten holes are drilled to the shift which would give fr from om sixty to one hundred drills to the two sharpeners sharp eners the Home homestake stake company is noted for the deep holes drilled for blasting work most of them being about twelve feet deep and from that to eighteen and twenty feet the holes start with a two and three quarters inch drill and drop to one and one half inch before the hole bole is finished it often requires three shifts before all of the holes are finished ready for the final blast the 44 chambe chambering riny of a hole is quite a delicate undertaking and when the hole is finished a stick or two of powder is pushed clear into the end and there exploded A hole is made several inches in diameter and after clearing out the broken rock a larger charge of powder is put in and still another if necessary until the chamber is made large enough to take in two or three kegs of powder the last charge is usually 11 great enough to break loose several hundred tons of rook rock it is a difficult matter to get the drills all tempered to the same hardness some of them will last but an hour while a few instances have been noted where they have been used for two weeks |