available from akzo nobel coatings inc as a black barrier emulsion composition which is available a liquid the liquid emulsion may be sprayed and the solvent therein will evaporate relatively quickly leaving the substantially fluid impermeable coating thus this preferred coating may be regarded as a one part system of course other coatings are possible including the so called u201c two part u201d systems where two streams are mixed at the head of the spray gun and react with one another substantially instantaneously to produce the coating other coating approaches which will work in the present process include in mold paints or coatings based on polyurethane and or polyurea further instead of spraying a coating onto saddle 140 it is possible to affix a film which covers saddle 140 and separate pieces of film for covering v shaped portion 120 and u shaped portion 130 this film may be secured by any conventional means such as vacuum or mechanical means many other approaches to achieving the substantially fluid impermeable coating will be apparent to those of skill in the art having the present specification in hand as this point in the process saddle 140 v shaped portion 120 and u shaped portion.