Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work.

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Old February 23rd 08, 04:34 AM posted to rec.crafts.metalworking
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Default Lead in solder

One of many issues is the thermal expansion of component and boards.
Most of the time it is close, but he tin-lead gave some stretch.
This lead free is harder and causes parts to come off.

I have to debug my weather station - the outside unit has several
TSSOP packages - small thin leads that Gull-wing out the sides.
These traditionally spring off the pcb in massive thermal ratios,
but across the country they are in failure mode and I suspect
the packages should have been BGA or SSOJ with the J lead that pretends
to be like a ball.

I went through a lot of engineering and stress testing - you should have
seen my oven - Hot & cold oven about the size of my office - walk in -
and put entire computers within - have them cycle up and down in all sorts
of temps - and see if any part starts to creep or spring up.

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Founder
IHMSA and NRA Metallic Silhouette maker & member.
http://lufkinced.com/


wrote:
I'd like to know where he came up with that $280B figure.


I don't know, exactly, but in my assembly business, the time taken by
our assemblers to place a component on a circuit board using lead-free
pure tin solder is about twice as long as with tin/lead solder. So,
that may be where the amount came from. The machine placed components
using a paste of tin-silver-copper takes the same amount of time. The
pass through the convection oven is also about the same time.

The scary thing is what two of our customers reported in the last
couple of weeks. That is a perfectly soldered lead-free component,
soldered to a silver plated circuit board using tin-silver-copper
solder paste, popped off the circuit board, leaving a trace of copper
from the component where it had been soldered.

The actual lead-free plating on the copper component leads detached
from the component.

I have read that lead-free wave soldering will always begin to
dissolve the copper board trace into the molten solder. Same thing may
happen with lead-free solder paste and a convection oven when the time
of the paste being liquid is too long. I have not read about the
component tinning/plating also causing copper problems in the
component.

This happened on one component on one board out of many for two
different customers. Not the same component manufacture, either.

Paul


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Old February 23rd 08, 05:04 AM posted to rec.crafts.metalworking
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Posts: 506
Default Lead in solder

clare at snyder.on.ca wrote:
Virtually NONE of the connections in/on the microprocessors and
associated controllers (think Can-bus) are constructed with crimp
connections. They have ciecuit boards, which are soldered. Leadfre
solder is a total pain in the butt to work with, and ALL devices to be
soldered with lead free NEED to be specially made for lead free
solder. The problems with lead-free solder in electronics assembly are
legion.


SORRY! I keep forgeting that there all that electronic JUNK in a car.
To me "automobile" wiring is the things that were in cars back in the
"dim dark" years of 50s and 60s when I worked on my own vehicles. :-)
...lew...
  #13   Report Post  
Old February 23rd 08, 11:49 AM posted to rec.crafts.metalworking
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Posts: 463
Default Lead in solder

I have read all of the responses as of now to this thread and the one
contribution I will make is that you boys should not panic over these
ridiculus rules and regulations that the green police are trying to invoke,
because these are wars that have already been won. There have always been
Ralph Naders and the like, but they are their own worst enemy. Common sense
will always prevail and economics will rule supreme. Stupidity has it's just
rewards. Nader killed his own carreer and so has Al Gore. Patience is a
virtue. Just look what these guys do, they take undeniable observations and
distort the analyisis. Fortunately, only the uninformed buy in. As an
example, there are now a new class of companies that have been born just to
help firms recover from ISO 9000 and all the other "Do it anyway, even if it
doesn't add value" Standards.
Steve

wrote in message
...
I thought the people on this group would be interested int his
article:

http://www.pbs.org/cringely/pulpit/2...21_004346.html

It's about "green" lead-free solder has caused problems. It think the
money quote is this one:

"And if you think this problem is minor, I have been told that just
the cost of changing to lead-free solder stands right now at $280
BILLION and climbing. That cost is borne by all of us."

It even has some metal content...



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Old February 23rd 08, 01:36 PM posted to rec.crafts.metalworking
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Posts: 5,161
Default Lead in solder

On Fri, 22 Feb 2008 20:24:21 -0800 (PST), with neither quill nor
qualm, " quickly quoth:


I'd like to know where he came up with that $280B figure.


I don't know, exactly, but in my assembly business, the time taken by
our assemblers to place a component on a circuit board using lead-free
pure tin solder is about twice as long as with tin/lead solder. So,
that may be where the amount came from. The machine placed components
using a paste of tin-silver-copper takes the same amount of time. The
pass through the convection oven is also about the same time.


Hand-assembled articles are surely in the minority nowadays, eh?
I wonder if his figure includes the fried components due to grown tin
spikes, etc.


The scary thing is what two of our customers reported in the last
couple of weeks. That is a perfectly soldered lead-free component,
soldered to a silver plated circuit board using tin-silver-copper
solder paste, popped off the circuit board, leaving a trace of copper
from the component where it had been soldered.

The actual lead-free plating on the copper component leads detached
from the component.


Whoa! That's a new one. Luckily, I didn't do more than a day or two
of assembly inspection in my QA years (shipping and receiving was much
more fun), but that was before lead-free was politically curserect.


I have read that lead-free wave soldering will always begin to
dissolve the copper board trace into the molten solder. Same thing may
happen with lead-free solder paste and a convection oven when the time
of the paste being liquid is too long. I have not read about the
component tinning/plating also causing copper problems in the
component.

This happened on one component on one board out of many for two
different customers. Not the same component manufacture, either.


This does not bode well, and if it turns into a larger trend, what
will the cost be to resolder all the lead-free equipment with leaded
solder in the future? sigh

Peter Huber got it right in his book _Hard Green_. The soft greenies
are depriving today's and tomorrow's children of their parents' wealth
and futures. Maybe the rampant idiocy in the media can be stampeded
back to sanity, so the useless forms of green thinking are eliminated
from the public eye.

Has anyone found stats for "lives saved by moving to lead-free
solders", perchance? Any bets on the figure being low to none?

---
Every moment is a golden one
for him who has the vision to recognize it as such.
-- Henry Miller
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Old February 23rd 08, 04:41 PM posted to rec.crafts.metalworking
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First recorded activity by DIYBanter: Oct 2007
Posts: 362
Default Lead in solder

On Feb 22, 8:34 pm, "Martin H. Eastburn"
wrote:
One of many issues is the thermal expansion of component and boards.
Most of the time it is close, but he tin-lead gave some stretch.
This lead free is harder and causes parts to come off.

I have to debug my weather station - the outside unit has several
TSSOP packages - small thin leads that Gull-wing out the sides.
These traditionally spring off the pcb in massive thermal ratios,
but across the country they are in failure mode and I suspect
the packages should have been BGA or SSOJ with the J lead that pretends
to be like a ball.

I went through a lot of engineering and stress testing - you should have
seen my oven - Hot & cold oven about the size of my office - walk in -
and put entire computers within - have them cycle up and down in all sorts
of temps - and see if any part starts to creep or spring up.

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Founder
IHMSA and NRA Metallic Silhouette maker & member.http://lufkinced.com/

wrote:
I'd like to know where he came up with that $280B figure.


I don't know, exactly, but in my assembly business, the time taken by
our assemblers to place a component on a circuit board using lead-free
pure tin solder is about twice as long as with tin/lead solder. So,
that may be where the amount came from. The machine placed components
using a paste of tin-silver-copper takes the same amount of time. The
pass through the convection oven is also about the same time.


The scary thing is what two of our customers reported in the last
couple of weeks. That is a perfectly soldered lead-free component,
soldered to a silver plated circuit board using tin-silver-copper
solder paste, popped off the circuit board, leaving a trace of copper
from the component where it had been soldered.


The actual lead-free plating on the copper component leads detached
from the component.


I have read that lead-free wave soldering will always begin to
dissolve the copper board trace into the molten solder. Same thing may
happen with lead-free solder paste and a convection oven when the time
of the paste being liquid is too long. I have not read about the
component tinning/plating also causing copper problems in the
component.


This happened on one component on one board out of many for two
different customers. Not the same component manufacture, either.


Paul


Thanks for the heads up on the possible thermal problems. We just
build them as the customer requires, but very few customers even knew
lead-free was required for export to Europe. So, they are still in
catch-up mode! When and if we can get in on the engineering phase of a
product, I will suggest we look at the larger component packaging to
see if the leads or pads will allow for movement caused by expansion/
contraction.

For the edification of the other posters, most, if not all, circuit
boards with surface mount components will have at least one hand-add
that is either surface mount or through-hole. Also, most current
production surface mount components are ONLY available lead-free. No
choices.

Thanks, Paul



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Old February 24th 08, 01:32 AM posted to rec.crafts.metalworking
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First recorded activity by DIYBanter: Jul 2006
Posts: 1,852
Default Lead in solder

Gosh - I forget the name/number - but there is a lead frame metal that has
the same thermal expansion coefficients as does FR4. A large Canadian Telecom
required us to use it and the J leads. They had outpost (boondocks)
electronics that would suffer heat of summer and cold of winter.

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Founder
IHMSA and NRA Metallic Silhouette maker & member.
http://lufkinced.com/


wrote:
On Feb 22, 8:34 pm, "Martin H. Eastburn"
wrote:
One of many issues is the thermal expansion of component and boards.
Most of the time it is close, but he tin-lead gave some stretch.
This lead free is harder and causes parts to come off.

I have to debug my weather station - the outside unit has several
TSSOP packages - small thin leads that Gull-wing out the sides.
These traditionally spring off the pcb in massive thermal ratios,
but across the country they are in failure mode and I suspect
the packages should have been BGA or SSOJ with the J lead that pretends
to be like a ball.

I went through a lot of engineering and stress testing - you should have
seen my oven - Hot & cold oven about the size of my office - walk in -
and put entire computers within - have them cycle up and down in all sorts
of temps - and see if any part starts to creep or spring up.

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Founder
IHMSA and NRA Metallic Silhouette maker & member.
http://lufkinced.com/

wrote:
I'd like to know where he came up with that $280B figure.
I don't know, exactly, but in my assembly business, the time taken by
our assemblers to place a component on a circuit board using lead-free
pure tin solder is about twice as long as with tin/lead solder. So,
that may be where the amount came from. The machine placed components
using a paste of tin-silver-copper takes the same amount of time. The
pass through the convection oven is also about the same time.
The scary thing is what two of our customers reported in the last
couple of weeks. That is a perfectly soldered lead-free component,
soldered to a silver plated circuit board using tin-silver-copper
solder paste, popped off the circuit board, leaving a trace of copper
from the component where it had been soldered.
The actual lead-free plating on the copper component leads detached
from the component.
I have read that lead-free wave soldering will always begin to
dissolve the copper board trace into the molten solder. Same thing may
happen with lead-free solder paste and a convection oven when the time
of the paste being liquid is too long. I have not read about the
component tinning/plating also causing copper problems in the
component.
This happened on one component on one board out of many for two
different customers. Not the same component manufacture, either.
Paul


Thanks for the heads up on the possible thermal problems. We just
build them as the customer requires, but very few customers even knew
lead-free was required for export to Europe. So, they are still in
catch-up mode! When and if we can get in on the engineering phase of a
product, I will suggest we look at the larger component packaging to
see if the leads or pads will allow for movement caused by expansion/
contraction.

For the edification of the other posters, most, if not all, circuit
boards with surface mount components will have at least one hand-add
that is either surface mount or through-hole. Also, most current
production surface mount components are ONLY available lead-free. No
choices.

Thanks, Paul



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