[ARC5] Bare Aluminum USN sets.

[Taigh Ramey]

I think the white material found on the screws you are referring to may be "cad whiskers". It seems to be common on cadmium plated or cad I hardware found in old equipment. 

The current specification in aircraft hardware calls for Cad II plating which uses the same plating process but ads a passivation coating at the end to eliminate the cad whisker phenomenon. This passivation coating is what gives the hardware the gold tint. 

Cad II is not so desirable for our restoration work since it wasn't used in WWII so we often have to send off new hardware for re plating without the passivation.  

Taigh



On Oct 20, 2012, at 11:34 AM, "Kenneth G. Gordon" <kgordon2006 at frontier.com> wrote:

> On 20 Oct 2012 at 7:23, Mike Everette wrote:
> 
>> I agree... but moisture can, and does, creep under screw heads and
>> work its way down the threads of the screws. 
>> 
>> Just like penetrating oil.
>> 
>> I'll bet you've taken screws out of Command Sets and found them turned green.
> 
> ...or covered with white powder...
> 
> Ken W7EKB
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