The answer could depend on which Chem-Dip product you have. Berryman offers two different CHEM-DIP formulas.

One version is intended for general consumer use and comes only in 1-gallon paint cans (part #0996). It rinses easily in warm water, the color ranges from light brown to dark brown, and it has a mild, characteristic (almost burnt?) odor. It is safe on for use on plastic, rubber, and most paints. While 0996 is also safe for most metals, it can react with some grades of aluminum and aluminum alloys. Soak times for aluminum-based parts in 0996 should be limited to 30-60 minutes per dip with a maximum soak time of 4 hours.

The other CHEM-DIP product is our professional-strength version and comes ready-to-use only in 5-gallon cans (part #0905) and larger. (This product was recently discontinued due to EPA regulations). It is a biphasic (two-layer) product that when fresh has a yellow, passivating layer on top and an amber, active layer on bottom. Both layers darken as the product ages. It also has a persistent, antiseptic-like odor and is not intended to ever be mixed, agitated, or aerated. 0905 will adversely affect many types of rubber and plastic but is completely safe on all metals, including aluminum and aluminum alloys. Though 20-30 minutes is a typical soak time, extended soak times are permissible without damage to metal surfaces.