A strip caster (10) for producing a continuous strip (24) has a tundish (12) for containing a melt (14) and a pair of horizontally disposed water cooled casting rolls (22). The casting rolls are juxtaposed relative to one another for forming a pouring basin (18) for receiving the melt through a teeming tube (16) thereby establishing a meniscus (20) between the rolls for forming a strip (24). The melt is protected from the outside air by a non-oxidizing gas passed through a supply line (28) to a sealing chamber (26). Devices (29) for conditioning the outer peripheral chill surfaces of the casting rolls includes grit blasting nozzles (30A, 30B, 30C, 30D), a collection trough (32) for gathering the grit, a line (34) for recycling the grit to a bag house (36), a feeder (38) and a pressurized distributor (40) for delivering the grit to the nozzles. The conditioning nozzles remove dirt, metal oxides and surface imperfections providing a clean surface readily wetted by the melt.