There are about a gazillion reasons why the milling machine controller
might go haywire, such as a bad solder joint or because someone forgot
a decoupling capacitor. In my opinion the chance for that to be caused
by ESD damage is so small, I rather put the effort into building a
lexan enclosure that will catch the flying tool bits or invest the
money in personal protection equipment for mechanical hazards.
I understand why you would want to be fastidious about ESD damage in a
semiconductor plant, you don't know where the parts will end up and
must meet the quality requirements of all customers. But you don't
need six-sigma quality if you make some circuit at home or even
commercial prototypes. The other error factors such as improper
soldering, faulty design, etc. will far outweigh any chance of ESD
damage. Don't confuse the quality standards of industrial mass
production with someone soldering something together on his bench.
I understand that ESD damage may not show any immediate signs, but
even the cases where semiconductors have failed "for no apparent
reason" are exceedingly rare. There just aren't any significant number
of parts failing, so there is no possible payback for any measures
taken.
Now, any more examples of even suspected ESD damage anyone? Again, no
production line stories please! Home shop or development lab only, I
do not want to argue about one-in-a-million events.
ST
On Sat, Dec 24, 2011 at 10:39 AM, John Dammeyer <johnd@...> wrote:
> Not everyone who builds PCBs at home builds frivolous projects that do no
> harm when they fail. A failed milling machine controller that has the
> table move erratically destroys a tool bit snapping it off and flinging it
> across the room or into someone is always a possibility, even if small.
>