How Smoothing Pads Work

How Smoothing Pads Work

It's a Fine Line

"Resin based diamond pads are used to obtain a fine surface on your glass in preparation for a final polish with cerium oxide. The diamonds are enclosed in a phenolic resin and move around within that resin providing a very fine scratched surface on your glass."


Our resin based Diamond Smoothing Pads start with an optical synthetic felt at .050-inch thickness. We then mix synthetic diamonds formulated specifically for resin bonding with our phenolic resin and coat the surface of the optical felt. Finally we add a thin rubberized magnet to the back for easy application and removal from lap grinders.


Diamonds in a phenolic resin are not locked into place as they are with electroplated diamond disks, but will roll and move as it passes underneath the glass. This gives a much finer surface scratch on the glass even at rougher grits. A 325 grit diamond in a resin bond will leave a surface more like 600 or 800 grit, but with the longevity of 325 grit.

It's Important to Brush

Since Smoothing Pads use a resin matrix on a felt substrate, it is a porous material and will need to have the ground glass cleaned out of the pad from time to time. This is easily done with a wire bristled smoothing pad brush. Just run the brush from the center of the pad to the edge while the grinder is running with water and then flush with water to clear out the ground glass from the pad.

Keep Up the Good Work

Smoothing pads will wear out faster than electroplated disks due to the nature of the resin material. You can generally expect to use 3 to 4 Smoothing Pads in the lifespan of a typical plated disk. Once a Smoothing Pad has worn to the point where it needs to be replaced it can still be used after a new Smoothing Pad to cut your polishing time down dramatically.


Smoothing pads come in various colors that correspond to various grits. You will rarely need all these grits and for most processes 325 grit is more than sufficient to move from an electroplated 270 or 325 grit to a final polish with cerium. The Black 100 grit and Purple 220 grit are excellent for working larger surface areas for a pre-polish and the Red 600 grit and Blue 1200 grit work well for smaller precise pieces like scientific glass, silicon wafer, and lapidary.