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Tin Whiskers

Views: 2583

Samir Nagaheenanajar

#38340

Tin Whiskers | 9 December, 2005

So, I'm workin' my damn fax machine; unfortunately, it's one of the 1st generation fax machines, because in Riyadh, we get stuck with the old equipment, and then it gives a message on the LCD display: Paper Jam..so I get mad, and yell:

WHY DOES IT SAY PAPER JAM WHEN THERE IS NO PAPER JAM...I SWEAR TO GOD...ONE OF THESE DAYS I KICK THIS PIECE OF SH*T OUT THE WINDOW!

Then I took the controller board out, had it electron micro'd, a lo-and-behold, a Tin Whisker was shorting out 2 TO220 leads!

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#38342

Tin Whiskers | 9 December, 2005

Are you sure it was a whisker and not a peace of paperclip??

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Rob

#38343

Tin Whiskers | 9 December, 2005

Nah, couldn't have been a tin whisker, we keep getting told they're a myth, & we're getting excited over nothing.

A bit like the loch Ness monster or sunshine in the UK.

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URL

#38344

Tin Whiskers | 9 December, 2005

Are you using the machine correctly? Ya just can't slap any ol' paper in there. Or just could be a conspiracy!

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#38345

Tin Whiskers | 9 December, 2005

Dont tin whiskers vaporize if they short because of the current going through them? I also think they're a myth...

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Amol Kane

#38346

Tin Whiskers | 9 December, 2005

why in the world would you have a fax controller board electron microscoped?

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Peter

#38348

Tin Whiskers | 9 December, 2005

Yeah, that was a Horrible....horrible idea!

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ola

#38356

Tin Whiskers | 9 December, 2005

Let the MythBusters investigate it. They look professional...

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#38358

Tin Whiskers | 10 December, 2005

Tin whiskers are real and can cause serious problems. That's why NASA maintains a web page on the issue. [ http://nepp.nasa.gov/whisker/ ] and why space flight is is exempt from Euroland lead-free requirements.

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Sergei

#38364

Tin Whiskers | 10 December, 2005

This is absolutely true. We have spent more than 10.000 man hrs on this, investigating of a fail safe interconnection that need to last more than 50 years in extremely harsh conditions. Tin Whiskers was at our "ten most wanted" list to be solved. Background radiation and solar eruption could even in rare circumstance accelerate the growth. One could wonder why we need lead-free alloys in such, but in terms of reliability and strength, there can not be any lead involved, which will cause other defects/problems.

Hopefully our results in a near future will be at public, free to use, so that everybody can benefit from it. Unfortunately I am not in the position to decide this. I am just pleased to be able to share this little information into this forum. новая встреча or se you later.

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Kris

#38392

Tin Whiskers | 12 December, 2005

Hi Samir

can you post some pictures of the whiskers ? I would also recomend you post your pictures on the IPC listserve forum for lead-free where you will find a focussed group that will be very interested in your pictures.

http://listserv.ipc.org/archives/leadfree.html

Who made the fax machine ?

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Rob

#38410

Tin Whiskers | 13 December, 2005

Hi,

Sorry, English humour.

So as not to trivialise an issue so important - yes tin whiskers are a very real problem. I Don't know much about it though, as I didn't get past dendronic growth at Uni.

If I ever get the time I will educate myself on the issue.

N.b. in the NEMI pictures it appears that they are growing/forming along surface scratches in the PCB finish - from the direction of growth & the angular nature. Are they known to form in air? or is it always along a substrate?

Cheers,

Rob.

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Samir Nagaheenanajar

Samir Nagaheenanajar

#38418

Tin Whiskers | 13 December, 2005

patrickbruneel

#38419

Tin Whiskers | 13 December, 2005

Samir,

This growth doesn't look like a tin whisker which are needle like and very fragile (they don�t bend they break). I have seen similar growth in the past in an EMS defect analyses with connectors in stressed conditions. The growth seen was similar to the growth shown in your picture. The interesting part was that when we did a spectrum analyses the main element in the growth was lead.

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