Monday, February 26, 2018

Storing parts to minimize corrosion

U-Line has many sizes of VCI tubing that can be used to custom make bags
I stumbled across Volatile Corrosion Inhibiting bags while looking for blue bags for my tree shelter project.   Some people like using VCI bags for storing springs and delicate mechanical pieces-parts.

Fundamentals of VCI...a cure for insomnia

For those who like to fiddle with things on their own, placing a pad dampened with a drying or semi-drying oil like linseed or soybean oil in a sealed plastic bag with the parts is an effective way to protect them from corrosion.  The vegetable oil scavenges the free oxygen.

The usual caveats about cleaning the parts and lubricating before storing them apply.

Source of table

Not surprisingly, different materials have different rates of oxygen permeability.

To save you some eyestrain:

  • Natural rubber is ten times more permeable to oxygen than Low Density Polyethylene (LDPE)
  • Low Density Polyethylene is seven times more permeable to oxygen than High Density Polyethylene (HDPE)
  • High Density Polyethylene is seven times more permeable to oxygen than unplasticized vinyl
  • Vinyl is ten times more permeable to oxygen than Saran.

Flipped around and restated a different way....A Natural Rubber film will transmit almost 5000 times more oxygen as a Saran film of equal thickness.


  1. That's a very interesting tidbit Joe, thanks for sharing. I've recently purchased some ZeRust products for my gun safe, based upon the same vapor-release corrosion inhibition principles. If you have time, a couple of questions.

    Where do you get it from?

    Can this product be used effectively as a corrosion inhibiting gun sleeve, for storage?

    How long does the treatment last?

    I wonder if it would work with my vacuum packer, i.e. if the plastic has the same melting point as food storage sheathing?

    Appreciate the info - thanks!

    1. You might look here:


      Regarding the vacuum packer...It would be easy enough to simply seal the parts you want to protect inside a food storage bag along with the VCI materials. The corrosion inhibitor is transported as vapor.

      If sealed the protection should last for years or decades.

  2. Nice product lines...and appreciate the ideas too. Thanks Joe!