[Noisebridge-discuss] Buying ESD mats?

Tue Jan 28 19:49:02 UTC 2014

The function of the mat is to ground both the technician and the 
work-surface.  My understanding is that to properly do that, you need to 
be connected (via a wrist-strap) to the same ground that the 
work-surface is (or to the work-surface directly).  The ground in the 
wall-sockets is acceptable *if* it is up to code.  They have testers for 
that I believe.

A grounded wire attached to the body would help, but static can build up 
on the work surface too.  If the work was grounded, but the surface not, 
you'd end up with a potential discharge there too.

ESD can be a big deal. I've seen lab-coats with a wire-mesh embedded, 
connected to snaps in the front.  A professor told a story of where he 
used to work, they had a strict code of protection, consisting of a coat 
that is snapped properly, appropriate specialized footwear, and 
wrist-strap.  If you were caught once without proper ESD protection, you 
were given a warning.  Get caught a second time and you were told your 
last paycheck would be on its way.

I don't remember the name of the place, but they worked on medical grade 
and aerospace grade electronics.  The professor said the insidious thing 
about ESD is that it might only weaken a part, so the circuit appears to 
function, but breaks down a lot sooner than otherwise would, and 
sometimes in unexpected ways.

In that class when we were working with a mosfet, all the pins were 
connected to each other (so net 0v), until we assembled the entire 
circuit.  Made for an interesting failure mode when we forgot to 
disconnect the grounding.  It just always acted as a wire, not a mosfet ;-)

On 1/28/14 10:30 AM, Paul Monad wrote:
> If I understand, the function of the mat is to dissipate static 
> electricity by providing a ground for anything it touches while 
> providing a nonslip working surface.
>
> So, the mat needs to be electrically conductive and grounded.
>
> Would a grounded wire with attachments to work and body serve? Could 
> the ground in the electrically receptacles be used or would it 
> necessitate a different grounding point?
>
>
>
> On Tuesday, January 28, 2014 9:25 AM, Daniel Pitts 
> <Daniel at coloraura.com> wrote:
> That's kind of a question with a tautological answer.  It is a 
> man-made object, so of course we could make it.
>
> The better question is would it be cost effective or provide other 
> benefits to create.  Part of that would be to consider what equipment 
> and supplies are needed to produce the mats.
>
> I don't actually know much about them, but what I do know is that they 
> are partially conductive ("dissipative" is the term used).  I'm 
> actually surprised they aren't covering more surfaces at the space. I 
> was there last night for CHM, and people were soldering ESD sensitive 
> devices on a wood table.  Unless that table has properties I'm not 
> aware of, it could be the cause of damage to certain components.
>
> OTOH, I used to repair my old computers on an old carpet before I knew 
> any better, and never fried anything ;-)
>
> On 1/28/14 9:08 AM, immonad wrote:
> Are these somethings we could make?
>
>
> Sent via the Samsung Galaxy S™III, an AT&T 4G LTE smartphone
>
>
> -------- Original message --------
> From: Daniel Pitts
> Date:01/27/2014 4:06 PM (GMT-08:00)
> To: noisebridge-discuss at lists.noisebridge.net 
> <mailto:noisebridge-discuss at lists.noisebridge.net>
> Subject: Re: [Noisebridge-discuss] Buying ESD mats?
>
> Those look good, I think the price difference is in dimensions, and
> shipping (since I get free shipping with Amazon Prime). Might be good
> enough, depending on your work space and needs. If you include
> shipping, I paid a similar amount ($58 for mine, $50 for the same size
> one you listed), but I get it delivered in 2 days, not 1-2 weeks ;-).
>
> On 1/27/14 3:12 PM, Johny Radio wrote:
> > I just found some like the one you got, but much better prices. maybe
> > they're not as good tho!
> > added to same link i sent you before.
> >
> >
> > On 1/27/2014 1:35:54 PM, "Daniel Pitts" <Daniel at coloraura.com> 
> <mailto:Daniel at coloraura.com> wrote:
> >
> >> Ah, I missed those. There are two that would be suitable, but they're
> >> on the very small side, and they don't come with a ground plug. I
> >> ended up going with one from amazon:
> >> 
> http://www.amazon.com/gp/product/B009WU8J9I/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1
> >>
> >> Thanks for the suggestions though, I do appreciate it.
> >>
> >>
> >> On 1/27/14 10:11 AM, Johny Radio wrote:
> >>> A few of these items are marked "ESD" or "anti-static".
> >>>
> >>>
> >>> On 1/27/2014 8:30:31 AM, "Daniel Pitts" <Daniel at coloraura.com> 
> <mailto:Daniel at coloraura.com> wrote:
> >>>
> >>>> On 1/26/14 11:45 PM, Johny Radio wrote:
> >>>>> On 1/26/2014 10:45:59 PM, "Daniel Pitts" <Daniel at coloraura.com> 
> <mailto:Daniel at coloraura.com>
> >>>>> wrote:
> >>>>>> I'd like to start doing some electronics projects at home. Any
> >>>>>> advice for buying ESD mats?
> >>>>>
> >>>>>
> >>>>> I recently researched this very topic. Here's what i found, when
> >>>>> looking for very cheap options:
> >>>>>
> >>>>> http://r.ebay.com/HOHakQ
> >>>>>
> >>>>>
> >>>> From what I can tell, none of those provide ESD protection. They're
> >>>> for heat protection. The certified ESD mats I've found are in the
> >>>> $60+ range for 2' by 3'. I'm all for cheaper, but I'll be
> >>>> occasionally working with MOSFET and CMOS, and I'd rather not burn
> >>>> them out ;-)
> >>
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