Corrosion Protection

From Matronics

Contents

Overview

Proper corrosion protection will extend the life of your airframe significantly. This subject has been debated many times. This page aims to bring a collection of research together in one spot.

Corrosion Prevention Chemicals

IMPORTANT: READ VENDOR-SPECIFIC MATERIAL SAFETY DATA SHEETS (MSDS) PRIOR TO USING ANY CHEMICAL

The following chemicals have been used and/or recommended for treating aluminum by builders.
Chemical Suppliers Application Pros Cons
Zinc Chromate (MSDS) Aircraft Spruce (Catalog) Aerosol Time-tested; used for decades in the aviation industry Health risks; Known carcinogen.
Zinc Oxide Aircraft Spruce (Catalog) Aerosol Less health risk than Chromate-based pigments ?
Cortec Zenith Aircraft Brush-on Less airborne particles than aerosol-based primers ?



The following chemicals can be used to prepare aluminum for corrosion protection application.

Chemical Suppliers Application Used For
Alumiprep Aircraft Spruce (Catalog) Comes in a bottle
Alodine Aircraft Spruce (Catalog) Comes in a bottle

Aluminum Treatment Techniques


General Information

  • "Corrosion Protection Answers": On INTERNAL corrosion protection, adhesion, surface prep techniques, use of automotive primers. A nice bit of information from PTI as part of the analysis. This thread recommends inexpensive preparation of aluminum by using a rag and isopropyl alcohol. It also recommends against using automotive primers, even if they are zinc chromate based.
  • Where can I buy Cortec 373? - Describes how to apply 373. You can get Cortec from Zenith. Recommends wearing a respirator during application of Cortec, along with good ventilation.
  • Newbie building CH701 - Corrosion / Gotchas - 1 2 3 4 - A thread featuring the following topics: thinning and application of cortec; metalprep 79, automotive primer, sacrificial zinc anodes, seaplanes, aluminum prep with soap, scotch brite #7557, zinc chromate on exterior rivet lines, more.
  • EAA Chapter 1000 - Corrosion Control Articles - A nice collection of articles related to corrosion.
  • How many don't use some kind of anti-corrosion primer? - Recommendations derived from the advice of a head metallurgist at a major aluminum smelter. Concludes that 6061 probably doesn't need additional protection, but suggests applying to mating surfaces if flying near the ocean.
  • Cortec 373 - Safety concerns, cleanup procedures, etc.