On 2013-01-29, Doug McDonald wrote:
The real state of the art for pinholes is twofold:

1) Laser drilling or 2) spark erosion drilling

Both make nice pinholes down to about 0.001 inch. Lasers go smaller.

One can buy such pinholes at reasonable prices (i.e. a few to a few tens
of dollars).

Doug McDonald

Oddly enough, though, whereas I can easily lay hands on a bit of bean can
and a nail and a rough lump of rock (or even a hammer and a file!), I can't
seem to find either a laser drill or a spark erosion drill in my tool box
)

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