Steve,
I dont have all the details on this one but I can get you started.
There is a MIL spec plating process that gives good grounding connectivity and retains corrosion resistance.  It is Chromate based and can be applied to Zinc and Aluminum, and other's I guess.  The chromate is put on very thin.  That's all I know.  I will forward more info if I can get hold of the ME that used this process.

---------------------------
John Laur
Rockwell Automation
Allen-Bradley Co Inc.
1201 South Second Street
Milwaukee, WI 53204
+1 414 382 2162 (fax)
+1 414 382 2393 (phone)

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---------------------------


> From: Steve Collins <[log in to unmask]>
> Subject:      [TN] DES: PCB Mounting
> To: [log in to unmask]
>
> Looking for inf. or specifications regarding mounting of PCB's into casting
> and metal housings. Specifically screws (self tapping), lockwashers,
> torquing requirements, grounding issues, durability of screws/ mounting
> hole thread requirements. Do any of the IPC spec's delve into any of these
> areas?
>
> Steve Collins
> PCB Design Supervisor
> ANTEC Network Technologies
> [log in to unmask]

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