Steve Damschroder

Topic: Cleanliness of machined aluminum castings

We are a medium sized aluminum foundry and machine shop and are having difficulty meeting cleanliness requirements of max chip size 750 x 75 x 75 microns and no oxides (sand grains). We clean the parts several times in a cabinet washer and patch test three times, all pass, but then get failures at the customer after the parts "bounce down the road" to the customer. The failures are for both chip size and oxides. Has anyone found a solution to this dilema?