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Gunner Asch[_6_] Gunner Asch[_6_] is offline
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Default What causes this?

On 28 Oct 2011 01:42:54 GMT, "DoN. Nichols"
wrote:

On 2011-10-27, wrote:
http://www.flickr.com/photos/2768312...in/photostream

Previously when I saw pits like these I thought it was caused by pin
holes in the resist. There was some discussion about its here. I
firmly believed that it was the hydrogen bubbles cavitating causing
this. However, in this case there is *no* resist!


Are those truly pits, or are they projections? I could imagine
air bubbles (or hydrogen) forming on the surface which would prevent as
much access from the etchant.

Either tapping the edge every so often, or applying ultrasonics
from a cleaner might break them up fairly quickly.

Good Luck,
DoN.


I think DoN has the answer.

Gunner

One could not be a successful Leftwinger without realizing that,
in contrast to the popular conception supported by newspapers
and mothers of Leftwingers, a goodly number of Leftwingers are
not only narrow-minded and dull, but also just stupid.
Gunner Asch