Modern Blacksmithing Rational Horse Shoeing and Wagon Making

with rules, tables, recipes, etc., useful to manufactures, blacksmiths, machinists, well-drillers, engineers, liverymen, horse-shoers, farmers, wagon-makers, mechanics, amateurs and all others who have occasion to perform the work for which this book is primarily intended. by J.G. Homstrom 1901

Twist Drills

Twist drills are not easy to make by hand, as they should be turned to be true, but a twist drill can be made this way. Take a piece of tool steel round and the size of the chuck hole in your drill press. Flatten it down to the size wanted, heat, put the shank in the vise, take with the tongs over the end and give one turn to the whole length, turn to the left. When finished be sure that it is not thicker up than it is at point, and straight. Now harden, heat to a low cherry red, cool off in luke-warm water-salt water, if you have it-brighten it and hold over a hot bar of iron to draw temper, cool off when brown, the whole length of the twist should be tempered.

Another way to make a drill is to just flatten the steel and shape to a diamond point and bend the shares forward. This is a simple but good idea and such drills cut easy. In cooling for hardening turn the drill in the water so that the edge or shares are cooled in proportion to point, or the shares will be too soft and the point of such a drill too hard. Our trade journals, in giving receipts for hardening drills, often get watch-makers receipts. This is misleading: watch-makers heat their drills to a white heat. Now, remember, as I have already said, when your drill or tool of this kind is heated to this heat the best thing to do is to cut that part off.

It is different with watchmakers; they do not look for strength, but hardness. They run their drills with a high speed, cut chips that cannot be discerned with the naked eye, and must have a drill that is hard like a diamond. For drilling iron or steel the drill does not need to be so very hard, but tough rather, because of the slow speed and thick chips. Few smiths have been able to master the simplest tempering, and they think if they could get a complicated receipt they would be all right. We are all more or less built that way. Anything we do not understand we admire. Simple soft water and the right heat are in most cases, the only thing needed for hardening. I had occasion to consult a doctor once who was noted for his simple remedies. A lady got some medicine and she wanted to know what it was so she could get it when the doctor was not at home, but he refused to reveal it to her. When the lady had left the doctor told me the reason why. "This lady said the doctor "does not believe in simple remedies which she knows, but believes in those remedies she knows nothing about it. I think it is better for us to try to understand things and not believe much in them before we understand them.




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