These Veritas Silicon Carbide Lapping Grits are to be used in conjunction with a flat lapping surface, such as the GSP-1, Granite Surface Plate.
Silicon carbide is ideal for flattening oil and water stones or lapping plane bottoms and blades. Just sprinkle the grit on a piece of glass or other ultra flat surface; add a shot of oil or water (as required); and lap the item flat. This fast and easy process lets you keep all of your stones dead flat. 90# is used for most applications; while the finer grits are used to put a silky finish on plane bottoms or blades.
Using PSA-backed plastic laminate sheets on glass speeds up the process; but is not mandatory. We offer a range of grits, but we recommend 280# for twisted, wavy or linished objects, 400# for ground surfaces with a slightly rough texture, and 600# for surfaces requiring little material removal.
While any grit size will ultimately achieve the same end result (since particles become progressively finer during the lapping process), the coarser the abrasive, the longer it takes to achieve.