Imagine you’ve just installed a job using stainless steel fasteners. You shake the customer’s hand, bank their cheque, and you’re a happy camper. Four weeks later the phone rings with a very unhappy camper on the line – “my stainless screws are rusting!”.

What is iron contamination?

Iron contamination causes rust staining on stainless steel. Stainless Steel has a Chromium Oxide passive film on its surface to prevent the Iron in the steel from oxidizing and forming rust. If loose Iron particles end up on the surface, these can oxidize to form rust and kick start corrosion.

How do I avoid iron contamination to prevent rust?

It is important to follow guidelines when using stainless steel, such as that any tools you use with stainless steel fasteners or hardware should only be used with stainless steel, and not also used on carbon steel fasteners where they could bring access loose Iron particles from.

- The driver/screw tips you use to drive the screws should be Chrome Vanadium steel.
- Allen Keys should be Hardened-Chrome plated.
- Cutting wheels should be made from Aluminium Oxide, be ‘Iron’ or ‘Carbon’ ‘free’, or be labelled “For Stainless Steel”.
- Hammers should be good quality Hardened-Steel or Hardened-Chrome plated. You can also get covers for the hammer ends to be used just for stainless nails.
- These tools should be kept just for stainless steel.

Let us know if you have had any bad experiences with tool contamination or have any other tips.

Disclaimer: This article is meant as a guide. Anzor Fasteners Ltd does not accept any liability for the application or use of the information in this article.