Grinders (General and Delta)

Using a low revolution grinder (1700 to 2000 rpms) can be damaging to tools. It is best to replace the original grey polishing stone that comes with most grinders with a white aluminum oxide one. This is because the grey stones are harder and will heat up the blades during the sharpening process. Polishing requires a felt wheel, positioned so that it is turning upwards. The white grinding stone should be turning in the opposite direction (downwards), towards the sharp edge of the blade. It is best to use a 100 or 120-grain stone. Remember that a finer grain stone will remove less material, cause more friction and heat. If you wish to use a fine grained stone to shorten the polishing stage, remember to cool the blade by dipping it into water. It is important to keep the blade warm and avoid extreme temperatures prior to cooling. The contrast between hot and cold will damage the blade's steel.

When polishing, use a green polishing compound (2000 / 3000 grain) with a ¾ medium felt wheel. Be careful not to apply too much pressure or leave the blade longer than necessary on the wheel, as heat caused by friction would damage the blade. Polish the bevel edge of the blade first, to a mirror-like finish. Then hone the other side to remove any excess metal. Honing must be done on a light angle to avoid dulling the bevel side of the blade.