In over 1 year of playing with microcontrollers and doing all kinds of bad things to them (not minding ESD, inadvertently shorting pins, sloppy soldering, etc.) I have burnt exactly 1 chip valued at $6 and I think that was due to writing the wrong fuses.
For statistics purposes, humidity is 30-50%, I'm wearing cloth slippers with plastic soles, and the floor is varnished.
Now, I've been playing with electronics consistently for 1 year, but I worked in risk management for 6 years. Any discussion where risk is hard to quantify is prone to people taking extreme stances. What's difficult is striking a balance and I guess we have to at least thank Stefan for challenging the traditional view. Make a short visit to
http://en.wikipedia.org/wiki/Logical_fallacy and identify quite a few appeals to authority in this thread before you hopefully draw the logical conclusion that for the proposed target group (hobbyists) there is indeed a lack of statistical evidence.
Quantifiable loss is a function of loss per event (how much money, time or annoyance I waste due to ESD risk materializing) and frequency/probability of occurrence (how many times ESD risk does materialize). That's why when once in a few years when building my computer or disassembling my laptop (hundreds of euro devices) I take all ESD precautions because I can't afford the risk. Similarly when working with mains I take all possible precautions including having someone in the room at all times.
But when playing with my $5 TI launchpad I stay on my leather recliner with my laptop on one side and with the USB board hanging next to it. I would regret my convenience more by obeying the "rules" then having my board toasted once.
I won't sweat over the principial concern that I am going to build an unsafe machine. If I depend on the safety of my build I am hiring someone to do the job.
In a business situation the picture changes radically. I would probably go with the conventional wisdom there without questioning it if I afford the cost.
--- In Homebrew_PCBs@yahoogroups.com, "within walking distance" <wkehr@...> wrote:
>
> --- In Homebrew_PCBs@yahoogroups.com, Stefan Trethan <stefan_trethan@> wrote:
> >
> > People who say "because that's just how it is" or "end of discussion"
> > as a rule are not worth my time talking to.
>
> Some things are pretty much self evident. Using the automobile example, you might say that a car has to have brakes, end of discussion. Just as don't cross the street blindfolded, end of discussion.
> To an electrical engineer, this might be self evident. Considering the amount of silvery antistatic envelopes, pink foam, pink bubble wrap, and black conductive foam that I have been sent with components that I have ordered, it seems self evident to the manufacturers and sellers.
>
> > From: Stefan Trethan Sent: Saturday, December 24, 2011 02:28
> >
> > Come on people, stay realistic.
> > Steve is most likely not going to make assemblies for an aircraft
> > or anything like that.
> Whether it's a controller for an aircraft or a blinking led for a child, he doesn't want a failure in either case.
> >
> > In a typical home shop or even development lab setting you'll not
> > notice the effects of ESD measures - there just aren't any failures
> > even if you take no measures at all.
>
> I use the SMD to DIP adapters. This gives me the advantage of being able to test the SMD device before placing it in the finished circuit. I've had more than my share of devices that did not sit correctly on the pads and therefore did not work. But in all this time there have been two devices that were soldered exactly right (close up lens on digital camera to check) , that did not work right. One part did not respond at all and one part had some gates working and some not. These both happened during the winter (low humidity) while I was working in a carpeted room. The same circumstances where petting my cat will give us a shock. I now have a dedicated wire running from the metal legs on my table to a nearby cold water pipe.
>
> > Mike KC7NOA wrote�.
> >
> >I wouldn't use it ... I would pintch a stop sign for a flat aluminum > surface first!!
>
> Taking apart old electronic devices that have been thrown away, like fax machines, can yield aluminum for making this. An old, large UPS might even have some giant heat sinks where the fins could hold circuit boards.
>