Our boys hung up another sign at this stage, and it read, "Keep your tools sharp." This ought to go without saying, but it is a fact that many people make failures of their work and become disgusted with it because they do not keep their tools in order. The satisfaction of using fine, sharp tools cannot be explained; it must be experienced.
Like other things about the shop, there are many kinds of grindstones on the market. The old-fashioned stone with a wooden frame ([Fig. 113]) worked by hand or a treadle may be good—it depends on the stone—and the new one with a small stone, iron, or pressed steel frame is handy. The last stone is provided with a bicycle seat, and is worked by both feet, so that the hands are free to hold the tool. This stone has ball bearings, is noiseless, and occupies less space than the other.
A stone that is soft and gritty, rather than one that is hard like a piece of granite, should be selected.
In holding the tool against the stone, some common sense is necessary. The harder one presses, the quicker the grinding, but if there is not plenty of water on the stone, the tool may be "burned." When a black place appears, you have destroyed the temper, showing that there has been too much pressure, or too little water, or both.
Fig. 113. Two types of grindstone
The tool may be moved back and forth across the stone to keep its face true, but never up and down. This up and down motion is careless and gives the defective edge shown at b ([Fig. 112])—very bad grinding.
It is an easy matter to test your grinding by occasionally placing the blade of a try square on the bevel. If it is not straight, your grinding needs more care. Too much stress cannot be laid on the importance of this subject of grinding. It is the key-note of success. If you are careless in this particular, your work at the bench cannot be a success. "A good workman is known by his tools."