For safety and to prevent a sloppy waste of water the stone should turn away from the operator.
The best way to keep a stone moist is by a trickle of water from an overhead supply. Troughs of water suspended under the stone are unsatisfactory, because the water soon gets thick and unfit for use. Such troughs are forgotten when the job is done, so that one side of the stone hangs in the water. An overhead supply of water leaks away and no damage is done.
Grindstone frames are best made of wood 3″ x 4″ thoroughly mortised together and well braced with wooden braces and tied across with plenty of iron rods. A good grindstone frame could be made of angle iron, but manufacturers generally fail in the attempt.
There are good ball-bearing grindstone hangers on the market, both for hand crank stones and for belt use.
The belt is less in the way if it is brought up from below. This is not difficult to do. A grindstone turns slower than any other farm machine so a speed reducing jack may be bolted to the floor at the back of the grindstone a little to one side to escape the drip. This arrangement requires a short belt but it may have the full face width of the pulley as the tight and loose pulleys are on the jack shaft.
Emery Grinders.—There are small emery wheels made for grinding disks that work quickly and cut an even bevel all around. They are made in pairs and are attached to the ends of a mandrel supported by a metal stand which is bolted to a bench. The same rig is used for sickle grinding and other farm jobs.
Figure 36.—Emery Grinder. The illustrations show two kinds of grinding that double emery wheels are especially adapted to. To grind a mowing-machine knife it is necessary to reverse. By placing the rest opposite the center between the two wheels the bevel will be the same on both sides, or edges, of the section.