Three families for chamfering by hand: the conical cup wheel for marble and granite, the straight cup wheel (the ring cup) with M14 or 5/8-11 thread, the cup wheel for 45° mitres on tiles. Made in Luni, Italy, in resinoid-bond silicon carbide, grit sizes C16 to C400.
A cup wheel mounts on a hand-held machine and works the edge: it breaks the arris, opens the chamfer, evens out the bevel. It is the wheel the stonemason keeps on the bench for the details that the bridge saw cannot reach, and the one the installer uses on site, for finishing a window sill or a worktop.
We make them in silicon carbide, the grain that cuts marble and granite without loading, bonded with resin. You choose the grit, from C16 for roughing to C400 for finishing, and we set the hardness on the material you work. The same angle grinder also takes the semi-flexible disc, for surfaces.

For chamfering marble, stone and granite on hand-held machines. The conical cup is the classic cup wheel: the flared rim brings the grain onto the arris at the right angle without tilting the machine. Also available with a steel backing plate, for those who want it stiffer under load.
| Size | Fitting | Use |
|---|---|---|
| 110/90x60x22 | 22 mm bore | chamfers on marble, stone and granite on hand-held machines; also with steel backing plate |
| 110/90x60 M14 | M14 thread | chamfers on marble, stone and granite, M14 threaded spindle |
| 110/90x60 5/8" | 5/8-11 thread | chamfers on marble, stone and granite, 5/8-11 threaded spindle |
| 76/64x40 M14 | M14 thread | the small cup, for narrow chamfers and light machines |
How to read it: 110/90 is the outer and inner diameter of the cup; the third number is the height, in mm. Grit C16-C400, several hardness grades.


In the workshop it goes by the name of ring cup (in Italian, anellino): a cup with straight walls, phenolic resin bond, for hand-held machines with a threaded spindle. It is for chamfers on marble and granite where the vertical wall of the wheel has to follow the edge without digging in.
| Size | Fitting | Use |
|---|---|---|
| 100x46 M14 | M14 thread | chamfers on marble and granite on hand-held machines |
| 100x46 5/8" | 5/8-11 thread | chamfers on marble and granite on hand-held machines |
| 80x46 M14 | M14 thread | the smaller size, for narrow edges and lighter machines |
How to read it: 100x46 is diameter by height, in mm. Resinoid (phenolic) bond, silicon carbide grit C16-C400.

For grinding the 45° mitre, the “jolly” edge, on single-fired and double-fired ceramic tiles. These are wider cup wheels, made for the machine that finishes the tile edge at 45 degrees: the silicon carbide grain works the glaze and the body without chipping the arris.
| Size | Use |
|---|---|
| 150x70x20 | 45° mitres on single-fired and double-fired ceramic tiles |
| 180x80x20 | 45° mitres on single-fired and double-fired ceramic tiles, for larger machines |
Grit C16-C400.
The jolly is the 45° mitre on the edge of a tile: two pieces cut this way meet at the corner with no trim profile. On single-fired and double-fired ceramic it is ground with a silicon carbide cup wheel, like our 150x70x20 and 180x80x20, mounted on the mitring machine.


The letter C stands for silicon carbide, the number is the grit size: the lower it is, the coarser the grain and the more stock the wheel removes. We make cup wheels from C16 to C400, in several hardness grades: coarse grit to open the chamfer, fine grit to leave it clean and ready for polishing.
The hardness of the bond we set together on the material: a dense granite calls for a different wheel than a soft marble. If you are not sure which grit to start from, call us with the name of the material and the machine you use.
A different diameter, a different fitting, an intermediate grit or a steel backing plate on a size that is not listed here: we make cup wheels to drawing as well. Send us the sizes and the fitting, or a sample of the wheel you use today.