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Anti static bags

Started by Kipper4, August 17, 2013, 03:32:34 PM

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defaced

It's ok.  It happens to the best of us. 

I asked a similar question on a different forum a few years ago.  http://music-electronics-forum.com/t22239/
Some of the guys mention storing their parts just as you do in plastic drawers. 

Not having a known static discharge you can feel is not really applicable to electronics parts.  As an example, MOSFET gate insulation is a tiny piece of glass that's 20 volts thick.  What that means is that the glass is so thin it only takes 20 volts to punch through the glass (this is the gate/source voltage rating in the datasheet).  You can't feel a 20 volt discharge with your skin, but your part could be ruined with it.  Similarly, I've seen people post images of resistors - supposedly not sensitive to static - with holes punched through them from static discharge.  So have you damaged some of your parts - almost guaranteed (as have all of us aside from the super careful and strict adherers to anti-static practices).  But that's not the issue.  The issue is "will the part successfully perform its intended purpose for a reasonable amount of time in the service environment", and the answer to that is "most likely".  Thankfully stomp boxes (and music electronics as a whole) is a pretty uncritical application with lots of error for fault tolerance.  No one is going to die if your stomp box doesn't work - unlike a medical device or any other device we rely on for critical applications.  So don't go too hog wild, just be reasonable and don't do anything really stupid (like I did where I took out my high voltage MOSFETs and laid them on my couch before I knew better - they died which I found out after I used them).
-Mike

Kipper4

What about foil lined crisp bags (potato chips to our USA cousins) Will that work?
Ma throats as dry as an overcooked kipper.


Smoke me a Kipper. I'll be back for breakfast.

Grey Paper.
http://www.aronnelson.com/DIYFiles/up/

bluebunny

Quote from: Kipper4 on August 19, 2013, 02:08:44 PM
What about foil lined crisp bags (potato chips to our USA cousins) Will that work?

Nice idea, Rich.  Mmmm... crisps!   ;D

But seriously, aren't they plastic-coated foil, rather than foil-coated plastic?  I.e. the inside surface isn't metal?  Could be wrong.  Wouldn't be the first time...  ::)
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Ohm's Law - much like Coles Law, but with less cabbage...

defaced

Good question.  Take an ohm meter and measure the resistance of the skin of the bag (rest the probes against the bag surface, not stick them into the bag). I'd be concerned about the oils from the chips impeding solder-ability of the legs.  Oil is not a good thing to have around when working with molten metal.  And cleaning the bag seems like alot of work for little reward. 
-Mike

Kipper4

I just wondered because maybe yes the contact of the componants legs might be important with the foil but similarly wiehter the foil is sandwiched between plastic (which i doubt although i dont know) it would surely function to stop any currant from arcing through the surface as seen in the video above.
Just curious.
And i think a quck wipe with some strong iso alcohol would quckly get rid of oily deposits in the bag.
I'm not convinced of its effectiveness but it might provide a meantime solution until i can get some proper bags.
Ma throats as dry as an overcooked kipper.


Smoke me a Kipper. I'll be back for breakfast.

Grey Paper.
http://www.aronnelson.com/DIYFiles/up/

Hemmel

What about pushing the envelope and connecting a ground wire to the aluminum foil ?
Would that improve on the anti-static effect ?
Bââââ.

defaced

#26
Quote from: Kipper4 on August 19, 2013, 02:37:22 PM
I just wondered because maybe yes the contact of the componants legs might be important with the foil but similarly wiehter the foil is sandwiched between plastic (which i doubt although i dont know) it would surely function to stop any currant from arcing through the surface as seen in the video above.
Just curious.
And i think a quck wipe with some strong iso alcohol would quckly get rid of oily deposits in the bag.
I'm not convinced of its effectiveness but it might provide a meantime solution until i can get some proper bags.

Ok, I just watched the video.  He's not every explicit about this, but it is implied.  The metallic bags provide both conduction and dissipation while the pink plastic only provides dissipation.  Your potato chip bag will provide conduction (assuming it's actually got foil in it), but the surface plastic will still build a charge (it's not dissipative).  Aluminum foil is still significantly less work with known effectiveness.  

Quote from: Hemmel on August 19, 2013, 02:40:27 PM
What about pushing the envelope and connecting a ground wire to the aluminum foil ?
Would that improve on the anti-static effect ?
I'd say a grounded storage system would only be advantageous if your entire work system were grounded.  That's a manufacturing controls nightmare that would be beneficial in critical applications.  If you want to take all the fun out of building stomp boxes, instituting that level of control would be a great way to do it.  
-Mike

Hemmel

Quote from: defaced on August 19, 2013, 03:07:32 PM
If you want to take all the fun out of building stomp boxes (...)

That is SO NOT what I want to do !!!  :D
It's just that I have limited funds for this hobby and even though ICs are usually under 5$ (most are under 1$), I want to minimize the chances of wasting them because I wasn't careful enough with ESD.
Heck, I wear my ESD bracelet everytime I work on any circuit ! Even breadboarding stuff...
Bââââ.

mistahead

Static discharge is actually pretty hard to break things with, how many are you losing to what seems to be ESD?

I've seen/felt static arc between me and a CPU when it was being handed to me and was unable to error that chip using prime95 - gave up testing after around four days and nailed up a server with it for nearly two years.

Hemmel

Quote from: mistahead on August 19, 2013, 08:50:23 PM
Static discharge is actually pretty hard to break things with, how many are you losing to what seems to be ESD?

I'm not sure if I really lost any to ESD, but it seems my LM386 aren't working as they should. It was suggested I try to use a stripboard/veroboard template instead of just using them on a breadboard. I haven't been able to make any circuit using a LM386 work on my breadboard. Other circuits work, so I was suspecting bad chips, and after reading this thread I thought maybe I fried them.
Bââââ.

Kipper4

I'm sorted thanks guys a kind soul from here (you know who you are) sent me some in the post
BOOM Sorted
Ma throats as dry as an overcooked kipper.


Smoke me a Kipper. I'll be back for breakfast.

Grey Paper.
http://www.aronnelson.com/DIYFiles/up/