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Require rust prevention on black oxide part

2006

We are exporter of steel forged and machined product to our US customers. We are presently struggling with a rust problem on one of our component. We are presently manufacturing a wood cutter it is basically a forged component which is then machined, heat treated and finally teeth grinding is carried out. This is then sent for Black Oxide, now since it is a cutter so our basic requirement is adhesion (i.e. blackening remains even after cutting operation) after blackening WD-40 ⇦this on eBay or Amazon [affil links] is applied for rust prevention. Finally before packing the product its teeth are coated with wax. Now we are facing the problem here that our product starts rusting in the wax coated area (Wax coated area comprise of a cavity which is non-machined forging part and ground tooth). Rusting problem is basically encountered in the forged cavity. So we require some suggestion on this to prevent our parts from rust. Then other thing which we observed was that as the WD-40 has lower flash point it gets evaporated while wax coating , so we are also looking for some rust preventive with higher flash point somewhere 160-200 °C.
RANJAN SHARMA
- NOIDA, U.P., INDIA

The WD-40 ⇦this on eBay or Amazon [affil links] and hot-melt wax are not the most appropriate materials for this purpose.

The black oxiding process should include dipping in a water-displacing rust preventative that dries to a thin, dry-touch film. The black oxide chemical suppliers have such products. Don't know whether the US companies -- EPI / Electrochemical Products Inc. [a finishing.com supporting advertiser], Heatbath, John Schneider and Associates Inc., Luster-On Products -- distribute in India, but the Indian company Guardian Anti-Corrosives Private Limited surely does.
Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.