Virgil,

The answers the last three questions are yes, yes, and yes.
The last one is the:
1. loss of structural integrity
2. allowing outside harsh environments to reach the circuitry,
3. EMI and RFI along with possible grounding problems.

The metal housing was needed for a reason. A broken metal housing
can not accomplish it's designed functions.

David A. Douthit
Manager
LoCan LLC

Virgil Lenton wrote:

> Hi all.
>
> I’m hoping you can help me. I know very little about welding. We have
> some .093 aluminum that has been bent into a box shape and then seam
> welded. The seams are then ground smooth. On a few of these units, we have
> noticed what looks like a crack beginning to form at the weld at the lip.
>
> Further investigation has found that the welder used the wrong material to
> make these welds. Apparently, he used tungsten for steel instead of
> tungsten for aluminum.
>
> These boxes hold electronic equipment and are installed in vehicles, hence,
> a fair bit of vibration.
>
> What will the ultimate repercussions of this wrong tungsten be on the final
> structure of this box? Will the small cracks propagate along the weld? Is
> it likely that we will see these cracks on all units? Is there anything
> else I should be concerned with?
>
> Thanks in advance for any and all replies.
>
> Virgil
>
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