Training is the culmination of work of the smith. It has always been covered with mystery cover, about it the set of legends is put. Training try to reach metal durability. To check whether the knife is well tempered, it needs to be bent in vice from 45 ° up to 90 ° down. If training is made correctly, then the knife has to break only at deviation more than 45 degrees from vertical.
Instruction
1. To temper knife, make several plates of metal to make experiments. Heat the first plate unevenly from minimum to maximum temperature and lower in water or oil. In vice begin to break plate and on break find necessary to you by the size grain. If grain on break is not, then metal will have the bad cutting qualities, the break has to have coarse-grained surface. For example it is possible to consider break of large file, on perimeter it will have smooth break, but in the center there will already be already necessary granular surface. Having made such experiment, you determine the necessary temperature for heating.
2. Now you need to pick up the environment for training. It is possible to temper in water, in oil, nitrogen, and even to use mercury. After heat the plate should be lowered in oil which temperature 200 °, to sustain of 15 minutes till 2 o'clock, and then to lower in cold water. Sometimes for training use even liquid lead.
3. The environment for training can be alternated, having made double training or zonal. Continue your researches. Take plate, heat it to the necessary temperature, make training to such durability that the plate could break in vice if to reject it by 30 degrees from vertical, then holiday achieve that this plate could already break at 45 degrees. Using this technique, you receive maximum of durability and the good cutting properties.
4. Several general rules: the blade before training should be annealed, then there will be less cracks. Do heating slowly, evenly and as long as possible. Use the muffle furnace with adjustment. For tough training in liquid lower edge vertically and you hold not movably. If to do training in different environments, then the knife will serve longer.