aligned in spaced parallel relation to one another the rods 29 are held in parallel alignment by a plurality of support bars 30 that extend at right angles transversely there across as seen in fig5 of the drawings the support bars 30 themselves are radially spaced about an outer surface 22 a of the filter drum 22 each of the drum rods 29 are oriented with their respective u201c wide base u201d 31 of the triangle facing inwardly defining a contoured smooth interior surface 32 as best seen in fig6 of the drawings it will be apparent that the relative spacing between the adjacent rods 29 define the effective filter resolution i e grade or grid size of the filter drum 22 in this example an initial material contact area 33 within the interior of the drum 22 is of a relatively u201c fine u201d filter surface which extends approximately one third the overall length of the drum as seen in fig4 and 5 of the drawings the remaining drum interior surface at 34 has the respective rods 29 and their associated bases 31 spaced further apart imparting a relatively u201c coarse u201d filter surface which will allow selectively larger material particle size to pass there through referring now to fig1 and 2 of the drawings the multiple stage air washer 35 can be seen positioned directly below the filter drum 22 to receive selected recyclable abrasive blast media there from the multiple air washer 35 is well known within the art and is comprised of a vertical chamber having multiple deflection angularly positioned veins 36.