Abstract: A method of making a filter or screen can include directed a high pressure cutting jet against a hard material at a plurality of positions to be cut that are separated by a portion of the material that is to remain uncut. Prior to moving from a first position to a second position, the abrasive can be replaced with a liquid or gaseous interference medium in such a way that reduces an energy density of the cutting jet from an energy density sufficient to remove or cut the material to an energy density insufficient to remove or cut the material. Once moved from the first position to the second position, the interference medium can be replaced with the abrasive in such a way that increases the energy density of the cutting jet from an energy density insufficient to remove the material to an energy density sufficient to remove the material.