First, clean the surface of the potter's wheel thoroughly. Small pieces of any debris on the wheel head or the disc can cause an up and down wobble, and that will be transferred to to what you are grinding.
Firmly attach the included special zinc plated low profile bat pins to the wheel head. Regular bad pins will not work because they will stick up above the surface of the diamond disc. The thin low profile of the grinding discs keeps water in the splash pan during use. The two holes on the disc will not interfere with the grinding operation. If you are grinding an edge at an angle, avoid the holes, and use the interior part of the disc until the edge is smoothed off. This takes just a few seconds. You can also use a 1/8" bat underneath the grinding disc and use your regular standard bat pins. Zinc plated or stainless steel bat pins are best to avoid any possible rust (iron oxide) staining, and these are now included with all discs.
Place the diamond grinding disc onto the attached pins, just like you would a throwing bat. It has a coarse/medium side (120 grit) and a fine side (400 grit).
Use water with the disc. It is best to use a steady, continuous drip of water. Clean the disc with soapy water and a stiff brush occasionally to remove compacted material from between the diamond particles. It is a good practice to rinse the disc well, quickly brush it, and remove it from the wheel head, dry it off and put it away after you use it.
The diamond particles are much harder than any ceramic, and the discs should never completely wear out. They do, however, over time become “dull” because tiny pieces chip off and leave a less sharp cutting edge. This can be remedied some by reversing the direction of the potters wheel for an hour or two of use from time to time, thereby using a different edge on the diamond particles. A worn disc can be "dressed" by rubbing an aluminum oxide or silicon carbide dressing stick back and forth along across the stationary disc, creating new edges on the worn diamonds and removing some of the electroplated nickle bond, exposing more diamonds. This can all lengthen the life-span, but the discs will eventually have to be replaced. Each side is separately replaceable.
The two sides of the grinding disc are held together by a very strong magnetic rubber sheet. The alignment of the bat pin holes can sometimes slip in shipping or use and make it difficult to attach to the wheel head. If this happens, just pry the two sides apart and reassemble over regular 1/4" high bat pins to re-align the holes. Take care not to pinch your fingers when you do this, and that both sides are free of any debris. The diameter of bat pins, nominally 3/8” in diameter can vary between manufacturers. It is possible some bat pins may be too large for the disc and not slip into the hole. If this happens slightly file or grind down the diameter of the over-sized bat pin until it slips into the hole. or use a round file to very slightly enlarge the hole.
The photograph at the bottom of this page shows a large chip in the bottom of a vase before and after it was ground away.
TIPS FOR USING THE DIAMOND SATURATED POLISHING PADS