EVAPO-RUSTTM works through selective chelation at a pH of 6.1 to 7.0 (neutral). Selective chelation is a process in which a large synthetic forms a bond with metals and holds them in solution. Most chelating agents bind many different metals. The active ingredient in EVAPO-RUSTTM bonds to iron exclusively. It can remove iron from iron oxide, but is too weak to remove iron from steel because the iron is held much more strongly.

Q) Do parts have to be completely clean before immersion?

No. EVAPO-RUSTTM has detergent, which penetrate oils and dirt. However, surface contaminants do slow the process. The soils must be penetrated before EVAPO-RUSTTM can come in contact with the rust underneath. Soil residue will also shorten the life of EVAPO-RUSTTM. Heavy greases and cosmoline should be removed prior to de-rusting. Also, adding hazardous contaminants can change the disposal requirements.

Q) Will EVAPO-RUSTTM remove bluing and other oxide finishes?

Yes EVAPO-RUSTTM will remove these in 30 minutes. Anodizing will not be removed. Powder coating and paint will not be removed as long as the paints do not contain oxides.

Q) What if I have a multi-metal or multi-surface item?

EVAPO-RUSTTM will not harm copper, brass, aluminum, plastic, rubber or vinyl. Even more amazing, EVAPO-RUSTTM will not remove non-oxide coatings, such as paint or chrome that are still bonded to the surface. Do not use with Cadmium coated surfaces.

Q) I get a black film on some parts after using EVAPO-RUSTTM. What is it and how do I Remove it?

The black is carbon from the steel. Generally high carbon steel is used in making items that are flexible (e.g. springs, saw blades, etc.). High carbon steel and tool alloy steel items, when de-rusted, will have a darker appearance. Much of the carbon can be removed simply by wiping with a cloth.

Q) Can I spray EVAPO-RUSTTM on the rusted area?

No EVAPO-RUSTTM only works in the liquid form. When sprayed on a surface, the water in the solution will evaporate before de-rusting can be completed. It can however be sprayed on as a rust preventative.

Q) How long does EVAPO-RUSTTM last? Does it evaporate?

This question can be answered three ways.
1) One gallon of EVAPO-RUSTTM will remove the rust form up to 300 pounds of moderately rusted steel.
2) One gallon of EVAPO-RUSTTM will remove the rust from approximately 20 square feet of moderately rusted steel.
3) If you could scrape all the rust off and weigh it, one gallon of EVAPO-RUSTTM will remove just over ½ pound of rust. Only water is lost from evaporation, if any of the bath evaporates, simply add fresh water.

Q) How do I know when the bath is spent?

The bath will turn completely black and will not perform

Q) How do I dispose of the spent solution?

If no hazardous contaminants are introduces, only the iron contents of the solution should dictate the disposal method In most cases, it is sewarable. Always dispose of product per local, state, and federal regulations.