Flash Rust » initial conditions http://flashrust.org The real story of what flash rust is and how to cope with it. Sat, 27 Jun 2009 18:21:50 +0000 en hourly 1 http://wordpress.org/?v=3.0 VIS Guides and Initial Conditions http://flashrust.org/2009/03/15/vis-guides-and-initial-conditions/ http://flashrust.org/2009/03/15/vis-guides-and-initial-conditions/#comments Sun, 15 Mar 2009 16:00:32 +0000 charles frenzel http://flashrust.org/?p=236 Use of VIS Guides for Initial Condition
 Determine the initial condition of the steel before the flash rust forms.
 Initial condition is illustrated as painted or unpainted steel.
 Select a photograph that is similar to the initial condition

The inspector and the contractor should be aware that the initial condition of the steel can vary within a short area.

004-deteriorated-paint-compare-with-vis-standard-photo

The initial condition is deteriorated paint.

005-clean-to-bare-substrate-very-thorough-cleaning-with-discoloration-on-right-side-where-coating-was-not-intact

Example of Clean to Bare Substrate and Very Thorough Cleaning with discoloration on right side where the coating was not intact of adhered to the substrate.

 

There is a very slight yellow hue to the steel on the upper left that is the onset of light flash rust.  The condition of the steel under the paint is a mix of Grade D and Grade C.

 

If the coating is intact, the steel will look close to the original condition.  If there is corroded or pitted steel, there often is a very-dark discoloration – gray/brown to black- that cannot be removed by further WJ.

 

The coatings manufacturers have said that “Analysis shows that this thin film consists mainly of ferric oxide which is an inert material. Because it is tightly adherent, it does not present a serious contamination problem.”

 

Author’s note- This discoloration has been over coated since 1985 with no apparent effect on subsequent paint performance.

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