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Old 2nd Jun 2009, 23:07
  #34 (permalink)  
blakmax
 
Join Date: Jul 2008
Location: Australia
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Thumbs down How to waste time: do injection repairs

So the repair is to inject resin?

the MRR fix is to inject resin up into the crack, allow to cure and then perform the stated repair with resin and glass. If you read it carefully they also tell you to apply vacuum.
Let me assure you that this is totally futile. To achieve a bond, chemical reactions must occur at the interface between the resin and the surface. For these reactions to happen, the surface must be clean AND chemically active. The injected resin will cure but it will not bond to the surface. The only things achieved by resin injection is that the air gap is filled so it appears that the joint has bonded and you get the opportunity to sign off that the repair has been completed IAW the MRR. You will not make one ounce of difference to the strength of the component.

The Australian Air Force prohibited injection repairs in 1996. [DEF (AUST) 9005 Chapter 11].

I invite all manufacturers who use resin injection for MRR repair of disbonds to show any experimental or other evidence whatsoever that this method restores any bond strength.
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