[amphead]

Apparently there is a secret threat when removing lead from tin based electronic products:
http://www.vmecritical.com/columns/foreword/2005/8/

 

[amphead]

Not the kind of thing that can be easily removed with a razor and a little shaving cream!

 

[Log1c]

This is a bigger deal for electronics in space than it is on the ground.

 

[pinkfloyd4ever]

um is NASA really worried about RoHS compliance? I doubt it. They're not selling their stuff to the comsumer market, and I know there are exceptions in RoHS for military and healthcare applications, so I seriously doubt that NASA gives 2 craps about RoHS

 

[KerryKing]

The thing with the exceptions is that they will not be for ever, they will with some years in between see and retry the exceptions, so even if something has an exception now it could change in just c couple of years, I don't remember how often it would be but I think it was like 2 or 3 years between each vote...

And also I believe ROHS is only for those who sell items not for the ones who build it for themselves, but i can be remembering wrong, it was some time ago i took the ROHS course

 

[Log1c]

RoHS is for all items sold/imported in the EU save a couple exceptions.

Your own personal use you can still do pretty much what you want.

 

[KerryKing]

Quote:

Originally Posted by Log1c /img/forum/go_quote.gif RoHS is for all items sold/imported in the EU save a couple exceptions. Your own personal use you can still do pretty much what you want.

Ah yes forgot to say I am in the EU and took the course here ^^

And its good to see i have not forgotten all

 

[ericj]

tin whiskers are not a "secret" threat. Everybody in the electronics industry is accutely aware of them.

And yes, they are a problem. The old Bell company had issues with relays in their switching equipment that were caused by tin whiskers, way back in the dark ages.

A touch of lead solves a lot of problems.

Every manufacturer with ROHS compliant parts claims to have solved the tin whiskers issue with some other combination of minerals. Only time will tell whether they got it right or not.

FWIW i thought NASA was exempt, as is the military and the medical profession.

 

[Log1c]

Quote:

Originally Posted by ericj /img/forum/go_quote.gif tin whiskers are not a "secret" threat. Everybody in the electronics industry is accutely aware of them. And yes, they are a problem. The old Bell company had issues with relays in their switching equipment that were caused by tin whiskers, way back in the dark ages. A touch of lead solves a lot of problems. Every manufacturer with ROHS compliant parts claims to have solved the tin whiskers issue with some other combination of minerals. Only time will tell whether they got it right or not. FWIW i thought NASA was exempt, as is the military and the medical profession.

NASA doesn't count because its an initiative specifically for European Union member countries. Almost all military and medical stuff is exempt for some reason I don't know offhand.

RoHS and its successor WEEE are attempts to remove lead and other poisonous substances from consumer and industrial products that end up in landfills and 'supposedly' leak hazardous stuff into water supplies.

 

[MCC]

This is exactly the reason I always prefer to buy leaded parts. If given the choice, I never pick ROHS.

Sadly, this might not be the "environmentally friendly" thing to do. Until there's proof that the latest lead free components are reliable, though, I'm sticking with time tested leaded parts.

My entire computer is old enough to be non-RoHS, but newer products are all lead free. I really hate to see lead free solder going into things like 65nm CPUs where even a nanoscopic whisker can wreak havoc. Again, until proven...

 

[beerguy0]

Defense contractors are having huge heartburn over this. There is little history on lead-free solders, at least compared to leaded solder. The military is still pushing leaded solder for high-reliability systems. One problem is that as more component manfacturers to to Pb-free parts, they stop making the regular versions, as it's not cost effective to have two product lines when one is very low usage.

Military contractors have begun having Pb-free parts actually dipped in lead solder, so they can continue to use their traditional methods. Until Pb-free solders have a proven track record, they will likely continue to use this approach.

 

[threepointone]

yep--I'm pretty sure that none of the space organizations are going to be using lead-free solder. In fact, NASA has an entire page dedicated to tin whiskers: http://nepp.nasa.gov/whisker/
They've already lost two satellites from tin whiskers, iirc.

>>edit
http://nepp.nasa.gov/whisker/failures/index.htm
four lost satellites and four partly lost satellites due to tin whiskers. Rather expensive problem, eh?

 

[MCC]

Quote:

Originally Posted by threepointone /img/forum/go_quote.gif In fact, NASA has an entire page dedicated to tin whiskers: http://nepp.nasa.gov/whisker/ They've already lost two satellites from tin whiskers, iirc.

I found this page to be especially informative.

 

[XGJFilmsX]

tin whiskers are very well known, and the lead does help but they do not totally solve the problem.

 

[amphead]

There are also gold, silver and aluminum whiskers. he he
http://nepp.nasa.gov/whisker/other_whisker/index.htm