RoHS, Lead-free Solder, and "Tin Disease"

[K2PG]

The European preoccupation with real or imagined environmental issues, the resulting RoHS protocol (Regulation of Hazardous Substances), and the ripple effect on countries that trade with the EU countries will all have an effect on us and our hobby. Mouser Electronics and other parts vendors are already stocking RoHS-compliant parts and phasing out the noncompliant inventory, even for domestic U.S. sales. The EU has banned the use of lead in solder. Most solder used in electronics work is either 60% tin and 40% lead or 63% tin and 37% lead. The solder being substituted in the name of RoHS compliance contains between 95 and 96% tin, 3 to 4% silver, and 0.5 to 1% copper.

There's a problem with using pure tin or the new tin-silver-copper alloy for soldering connections. Tin is a highly crystalline metal that exists in two forms: the alpha or gray form, with a cubic crystalline structure, which is a very brittle material that readily crumbles into a powder and the beta or white form, with a tetrahedral crystalline structure, which is the familiar shiny metallic form of tin. When tin is cooled below 13.2 degrees Centigrade (about 56 degrees Fahrenheit), it slowly changes from the beta to the alpha form. This transformation was once called "tin plague" or "tin disease", as it initially looks like dark, warty spots on tin objects. The addition of antimony, lead, or bismuth to the tin prevents this transformation, but all three metals are taboo under RoHS due to their toxicity. Joints soldered with RoHS-compliant solder will disintegrate over a period of about 18 months to several years if they are exposed to low temperatures. The silver and copper will not prevent the beta-to-alpha conversion of the tin; in fact, copper may actually accelerate this change!

Another problem with using RoHS-compliant solder is the growth of "tin whiskers". Fine, crystalline needles of tin will extend from the soldered joint, causing short circuits and intermittents. The higher temperatures required for melting pure tin or the new tin-silver-copper alloy may also damage sensitive electronic components. The German amateur radio magazine Funkamateur ran an article some months ago about this problem.

Ironically, "tin disease" was first observed in Europe. Organ pipes were once made of tin. The tin organ pipes in northern European churches would start to disintegrate in the cold northern winters. Once thought to be the work of the devil, this "tin disease" was later shown to be a change in the crystalline structure of the tin, as the tin changed from the beta form to the alpha form...and the organ pipes eventually fell apart!

<sarcasm> You've just got to love the environmentalists! </sarcasm>

[Jim, W5JO]

Ironically, "tin disease" was first observed in Europe. Organ pipes were once made of tin. The tin organ pipes in northern European churches would start to disintegrate in the cold northern winters. Once thought to be the work of the devil, this "tin disease" was later shown to be a change in the crystalline structure of the tin, as the tin changed from the beta form to the alpha form...and the organ pipes eventually fell apart!

<sarcasm> You've just got to love the environmentalists! </sarcasm>

The home of Dracula, and other myths live!  Long live the paranoid.

[David, K3TUE]

Is there a solution in the works for this?  It sounds like they have put the cart before the horse here.

[w3jn]

All of the crap they're making now will be obsolete and unusable well before the tin whisker problem happens.  Unless they grow in 3 years or so.

[K1JJ]

Guess it's time to hit RatShack and blow a couple hundred bux on solder rolls before it's gone forever.

The cold problem bothers me. What do ya do with feedpoint soldered connections that are hung out on a Yagi in the WX? The temps get down below zero sometimes, never mind 56 degrees. Take it down every 18 months to resolder?
Like I said, Ratshack is about to be cleaned out.

Speaking of metals...  I use to buy 500' of #14 stranded insulated wire at Home Despot for $12.  I saw it there last week for $44.95 a roll!  That's about right considering copper on the futures exchange has gone from 70 cents to over $3 a pound.

T

[Jim, W5JO]

If you have an air conditioner compressor outside, watch it.  Down here they are lifting the things because they have so much copper tubing in them.  Take snips and cut the lines, reverse the cut out switch and away they go.  Crooks are also watching the electiician install wiring in new houses and stripping them the following night.  Security companies are making big bucks right now for guards.

[WU2D]

What a royal pain.

But apparently, it doesn't matter. Management told us 6 months ago that even though our industry was "100% exempt" from RoHS (defense industry is exempt), we would have to convert to lead-free. That was because they fear that all of our suppliers are going that way and we would have to convert anyway, so we might as well do it now.

We can not even add a part on a new design unless it has a RoHS certification. If no compliant part exists, the VP Engineering must sign off on a part by part basis.

Of course the initial results are showing quality problems, especially in ball-grid array SMD devices, but again it doesn't matter, we are being told that everybody will change over. We are also being told that it is costing a fortune for people to figure out how to deal with the change.

Compliance "experts and consultants" are making a fortune on this crap.

Mike WU2D

[k4kyv]

And the lead-free technology will be oriented towards surface mounted components.  I suspect there will be no solder on the market suitable for point-to-point wiring.  No doubt, the new stuff will cost several times what we pay at present.

I think I have a lifetime supply of lead/tin solder, that I have accumulated over the years - several 5 lb rolls.

Watch the price of lead/tin solder go sky-high until the supply is exhausted.

Wonder if they will still make lead/tin solder for non-electronic and non-electrical use.  I have seen rolls of solder that were nothing but the metal alloy wire - no core.  If that is still available, you can always go back to the method used back in the 20's and early 30's before rosin core solder was developed: use solid solder, and apply the flux separately.

The EU has gone even more berserk with this bullsh¡t than the US.  They have strict "health" regulations in place that forbid certain traditional methods of making cheeses, wines and other food delights that some of the European countries have been famous for, for centuries.  The cheesemakers are pissed off, but apparently no-one in the bureaucracy is paying them any attention, and the local governments are obligated to enforce the rules.  There is strong sentiment in UK (which hasn't changed over to the Euro currency) to withdraw from EU, but I suspect that has a snowball's chance in hell of happening.

I suppose next, broadcast stations will be afraid to release old transmitters because of the lead solder, just as many of them now are reluctant because of the PCB scare.

[WA1GFZ]

Anybody who ever worked for motorola in the '90s knows about tin wiskers in tuned cavity front ends. Mot had this VCO inductor that would go microphonic after a few years. We changed them out like underwear. Those stupid little trunking radios had a hunded screws if they had 50.
As soon as I heard lead was going away I made sure I bought a life time supply of real solder.

[W1RKW]

This environmental stuff is out of control.

[K1JJ]

This is the cheapest 1 lb roll of solder I could find that is 60/40, rosin and is at least .050" in diameter.  $7.25/ roll.  Ratshack gets about $12/roll now.

I ordered 12 rolls. I really don't believe that's a lifetime supply. It sure goes fast sometimes.

http://www.partsexpress.com/webpage.cfm?webpage_id=3&SO=2&DID=7&CATID=51&ObjectGroup_ID=361



Actually, the RatShack solder is usually 60 tin and 40 lead - This stuff is 60 lead and 40 tin. What is the problem using it, if any... weaker and lower temp melting?  I still have time to cancel the order.

The Kester solder is so much more expensive - wonder why?


BTW, I'm a little cornfused.. they all have different ways of describing the core. Some say, "rosin", while others call it "resin" and others say, "flux".  Hope I got the right thang. They do say it is for electronics.  I usually buy "rosen-core" solder at Ratshack.

T

[W1RKW]

Just ordered 6 rolls of Kester .062  60/40 tin/lead at $8.00 per 1lb roll.


This would be a PITA and add time to construction but one can always clip on a clip on heatsink to a heat sensitive component.

 The lower melting point would actually be an advantage for solid state work, as less heat is needed to melt the solder and less heat means less of a chance of damaging sensitive components.

[K1JJ]

Tnx for the info, Phil.

Bob, where did you order the 60/40 .062 for $8?   I might as well buy some more, cuz I'll use it within the next 20 years....

T

[W2JBL]

   damn tree huggers banned lead bird shot a while back. ammo makers scrambled for a replacement and came up with "hevishot", using tungsten instead of lead. now it seems the darn fool branch bangers found it in ground and swamp water too, so it's gonna be banned. yet through all of this (at least here in New York) it's actually illegal to shoot a bird with a (nice enviornmentally friendly) pure copper bullet. go figure!  i have been stockpiling lead solder for a few years now, and am ok for life. if you like anything containing lead, better buy now, or the tree huggers are gonna get you !

[John Holotko]

Ironically, "tin disease" was first observed in Europe. Organ pipes were once made of tin. The tin organ pipes in northern European churches would start to disintegrate in the cold northern winters. Once thought to be the work of the devil, this "tin disease" was later shown to be a change in the crystalline structure of the tin, as the tin changed from the beta form to the alpha form...and the organ pipes eventually fell apart!

<sarcasm> You've just got to love the environmentalists! </sarcasm>

The home of Dracula, and other myths live!  Long live the paranoid.

But Dracula IS real !!

[W1RKW]

Tom,
Found it on EBay.  There's a Buy It Now sale for 3 rolls at $22.00 plus $6.00 shipping of the same stuff I picked up here: http://cgi.ebay.com/Kester-Solder-3-Rolls-1-Pound-Each-Unused_W0QQitemZ190003832712QQihZ009QQcategoryZ109555QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Tnx for the info, Phil.

Bob, where did you order the 60/40 .062 for $8?   I might as well buy some more, cuz I'll use it within the next 20 years....

T

[K1JJ]

Tom,
Found it on EBay.  There's a Buy It Now sale for 3 rolls at $22.00 plus $6.00 shipping of the same stuff I picked up here: http://cgi.ebay.com/Kester-Solder-3-Rolls-1-Pound-Each-Unused_W0QQitemZ190003832712QQihZ009QQcategoryZ109555QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Got 'em!

Thanks for the hot tip, Bob....

T

[k4kyv]

Wouldn't steel birdshot be just as effective as copper?

Plain old steel is cheap and would quickly rust away.  Besides, copper has become a semi-precious metal these days.  And unllike lead, ground chemicals don't dissolve it right away.  That's why it is used for radial systems in commercial radio installations.

[KB2WIG]

   The mistake in your thinking is that you apply logic to New York State. This is a grave error in that logicit is not used up here....

[WBear2GCR]

Friends,

Buy the stuff that is 2% silver, also known as "Sn62" iirc. Not plubing solder, fyi.

In that it contains some silver it will not leach the silverplating from all sorts of things like Tek scope ceramic strips, silver plated wire, and of course connectors. It is also Eutectic.

Also 63/37 is far better to use than 60/40, since 63/37 is also Eutectic.

Which means it liquifies and solidifies at the same temperature - meaning you get better joints and fewer cold solder joints.

         _-_-WBear2GCR

[W1RKW]

Got 'em!

Thanks for the hot tip, Bob....

T

Excellent!
Anytime! You've helped me many times. Glad I could return the favor.

[k4kyv]

I use plumbing solder, or should I say brazing rods, for outdoor grounding connections as well as bonding together the radial system on my vertical.  The  stuff comes in a flat stick, about 1/8" wide and about 18" long.  No flux is required.  Once melted, copper seems to soak it up like a sponge soaks up water.  Just make sure the scaly stuff is removed, but no need to polish the copper to a bright finish.  It is unaffected by outdoor weather or ground minerals - even after 25 years.

It takes a Mapp Gas torch to melt it.  Propane doesn't get hot enough.  The copper has to be heated to a dull red glow.  Careful, when brazing radial wire - it is easy to melt the copper wire to a round blob by leaving the  heat on too long.

Less hassle than cad-welding and it appears to be just as permanent.

[John Holotko]

I don;'tunderstand the reasoning of this. I'm all for the idea of protecting the environment but banning lead solder before  their is a suitable substitute doesn't make a bit of sense. It is sort of like banning an important medical  procedure before a suitable alternative procedure is in place. What is the sense in banning  lead solder if the replacement solder is inadequate  and deterirorates in a few short years. Won't  that actually create more waste ? Imagine hiow many more electronic gadgets will end up having to be thrown awaybecause the solder joints disintegrate in record time. There are many more sensible ways that things can be made more environmentally friendly. This solder banning is just plain foolishness.

[W1RKW]

Unfortunately, the "knee jerks" know more than the experts.  And apparently there are more of them.

I don;'tunderstand the reasoning of this. I'm all for the idea of protecting the environment but banning lead solder before  their is a suitable substitute doesn't make a bit of sense. It is sort of like banning an important medical  procedure before a suitable alternative procedure is in place. What is the sense in banning  lead solder if the replacement solder is inadequate  and deterirorates in a few short years. Won't  that actually create more waste ? Imagine hiow many more electronic gadgets will end up having to be thrown awaybecause the solder joints disintegrate in record time. There are many more sensible ways that things can be made more environmentally friendly. This solder banning is just plain foolishness.

[Ian VK3KRI]

I don;'tunderstand the reasoning of this. I'm all for the idea of protecting the environment but banning lead solder before  their is a suitable substitute doesn't make a bit of sense. It is sort of like banning an important medical  procedure before a suitable alternative procedure is in place. What is the sense in banning  lead solder if the replacement solder is inadequate  and deterirorates in a few short years. Won't  that actually create more waste ? Imagine hiow many more electronic gadgets will end up having to be thrown awaybecause the solder joints disintegrate in record time. There are many more sensible ways that things can be made more environmentally friendly. This solder banning is just plain foolishness.

The expected lifetime of any consumer  electronic gadget is probably less than that of lead free solder anyway. Besides, if you ban lead based solder then market forces will surely devolop a viable alternative .

Then again my thinking could be fuzzy because of 35 years of exposure to 60/40 . I hope Ive got enough stored away for another
few decades.                                                                Ian VK3KRI