Back before I found compressed dehydrated sponges in the painting section of my local crafts store or gourmet kitchen sponges at a local kitchenware store, I wanted to put some sort of sponge in my pocket tin, so I resorted to cutting a piece out of a local supermarket's sponge cloth.
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I put it in my PSK...
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...and all seemed well.
But, when I opened my tin for annual inspection and maintenance, I found...
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...that something about the spongecloth had damaged the aluminum foil, merely by prolonged contact.
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Please note that all of these pictures were taken after
unpacking. The aluminum foil residue you see in the first image was not there when I packed it; nor was the rust you see in the second image. The rust, BTW, came from a safety pin, which was also ruined.
So...
The first lesson might seem to be:
This brand of sponge cloth is hard on metals. Don't use it. <img src="images/graemlins/mad.gif" alt="" />
The second lesson might seem to be:
Be careful with aluminum foil. Over time, and with pressure, it can be unexpectedly damaged, even in storage. <img src="images/graemlins/tongue.gif" alt="" />
And the third lesson might seem to be:
We should all periodically unwrap, untape, open and inspect all contents of any kits, tins or packages we use, carry, store or (perhaps especially) sit on. <img src="images/graemlins/laugh.gif" alt="" />