Hyprez Polishing Stones

Engis offers a complete range of vitrified finishing stones for hand and machine polishing applications. Our stones come in a wide variety of grit sizes and formulations to provide you with the right tool for each job. ® DiaMold stones are available in both standard and premium white aluminum oxide as well as green silicon carbide to cover a broad range of mold materials. Please consult the chart below to identify the right stone for your application. All of our stones are manufactured in the USA.

Page	Type	Abrasive	Color	Grits	Characteristics & Application
87	DM	Aluminum Oxide	Gray	150-600	Similar to the DS general purpose finishing stone. This stone is slightly harder and does not break down as rapidly as the DS. Engineered to cut very fast, yet provide a smooth finish. Excellent for removing cutter marks on all tool and die steels.
87	EDM	White Aluminum Oxide	Dark Brown	100-600	The EDM stone is engineered for the removal of EDM scale. This stone is a soft grade which breaks down fast and cuts freely. Specially designed for hand applications.
88	RG	Green Silicon Carbide	Green	120-600	A medium stone with premium silicon carbide grains. Cuts very fast, yet provides an excellent finish on most die and mold steel types ranging from 28 to 58 Rc. Also permits finishing on aluminum, cast iron and bronze.
88	DS	Regular Aluminum Oxide	Green / Tan	100-900	Very popular medium hard stone for all types of steel. Fast cutting, provides a fine, even finish and has the perfect breakdown for a finishing stone.
89	A/L	White Aluminum Oxide	Tan	150-600	A specially treated, medium hard stone that cuts fast and leaves an excellent finish. It works well on aluminum, not scratching or tearing the surface.
90	HY	White Aluminum Oxide	Cream / Ivory	120-600	Extremely well liked, this medium hard stone is treated with a special oil to resist loading. Cuts very fast yet provides smooth finishes on most tool and die sheets. 220 grit and 320 grits work well on hard EDM scale.

DM

This aluminum oxide stone is similar to the DS general-purpose finishing stone but slightly harder and does not break down as rapidly. It is engineered to cut very fast while providing a smooth finish. It is excellent for removing cutter marks on all tool and die steels. It is a general-purpose stone, fast cutting, with consistent breakdown, and suitable for use on all tool steels.

EDM

The EDM stone is engineered for the removal of EDM scale. This white aluminum oxide stone is a soft grade which breaks down fast and cuts freely. Specially designed for hand application.

RG

A medium stone with premium silicon carbide grains. Cuts very fast, yet provides an excellent finish on most die and mold steel types ranging from 28 to 58 Rc. Also permits finishing on aluminum, cast iron and bronze.

DS

Very popular medium hard aluminum oxide stone for all types of steel. Fast cutting – provides a fine, even finish and has the perfect breakdown for a finishing stone.

A/L

A specially treated, medium hard white aluminum oxide stone that cuts freely and leaves an excellent finish. It works well on aluminum, not scratching or tearing the surface.

HY

Favored by professionals, this medium hard white aluminum oxide stone is treated with a special oil to resist loading. It cuts very fast yet provides smooth finishes on most tool and die sheets. 220 grit and 320 grits work well on hard EDM scale.