>Here's a shot of this technique courtesy of Tony K's web site.
I think I had seen this already on Tony's site (and BTW it's probably a
good idea to just post a _pointer_ to a publicly available file like this,
rather than posting a copy to the list, especially a non-text file - see
the FAQ).
However, I studied it a bit more closely this time and it appears to me
that some of the drillings have almost started to break through to the
inner surface - am I imagining it, or are there slight bumps on the visible
part on the inside? If so, this is probably bad news ....
Any drilling like this needs to be done to a carefully set depth stop using
a bench drill, _not_ a hand-held one, with the workpiece supported in a
precisely repeatable way for each hole location.
regards
Rowland
... that's Rowland with a 'w' ...
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