60/40 vs. 63/37 Solder

[GregS]

In article <i1p4j1$t6b$1@news.eternal-september.org>, "William Sommerwerck" <grizzledgeezer@comcast.net> wrote:

Rosin flux can be removed with 99% isopropyl alcohol
($1 a bottle at your corner drug store).

You won't find 99% for $1. (91%, maybe.)

If you can get 95% ethanol, I thinks its best. By the time
you use 98 or 99% it absorbs water anyway on the board,
and you still have a water residue. You can also drink it.

greg

 

[Jim Yanik]

"William Sommerwerck" <grizzledgeezer@comcast.net> wrote in
news:i1ovm1$ccb$1@news.eternal-september.org:

The only reason 60/40 was ever manufactured in the first place is
that tin is more expensive than lead, so 63/37 solder costs more.

Cite, please? (and I don't mean a link to commodity prices)

I can only cite "common sense". 63/37 has always been
more-expensive than 60/40.

Then you can't substantiate your contention that 60/40 was THE
worldwide standard for tens of years just because it was a few
pennies cheaper per pound? That is the statement of yours with which
I take issue.

I have no objection to your objection.

However, 60/40 was never, ever, "a few pennies per pound" cheaper than
63/37. For the last 30 years, the price of eutectic solder has been
sufficiently higher to make one think twice before buying it. The last
time I purchased solder, I decided that a one-pound roll of Kester 44
would last the rest of my life, and I splurged. (At this point in my
life, my prediction is coming true. I rarely solder any more. If I
drop dead, someone digging through the junk will find a pleasant
surprise. Assuming they know what 63/37 is.)

I just checked Parts Express, and a 1# roll of Kester 44 60/40 is
$22.23. 63/37 is $26.85. That's a $4.62 difference, almost 21% more --
hardly "pennies per pound". When I bought the same product some years
back, my memory is that the price was around $7.50 for the 60/40, $9
for the 63/37. Even that wasn't "pennies per pound".

I looked at the MCM site for Ersin products. Get this... MCM describes
its house brand of 60/40 solder as "provid[ing] the lowest possible
melting point".

Businesses almost always try to cut every corner they can. If you
think your solderers -- or soldering machines -- are doing a good job,
you might prefer to buy the less-expensive 60/40.

When I worked at Bendix Field Engineering, I often walked through the
section where a bunch of women (never men) soldered assemblies,
following NASA standards. I never thought to ask whether they used
60/40 or 63/37.

maybe the price difference is due to "new and improved" rather than any
other reason.

BTW,63/37 has the lowest melt point of all the tin/lead alloys. 361 deg F

--
Jim Yanik
jyanik
at
localnet
dot com

 

[Jim Yanik]

"William Sommerwerck" <grizzledgeezer@comcast.net> wrote in
news:i1p4j1$t6b$1@news.eternal-september.org:

Rosin flux can be removed with 99% isopropyl alcohol
($1 a bottle at your corner drug store).

You won't find 99% for $1. (91%, maybe.)

91% is what CVS sells,I don't recall the price,though.

--
Jim Yanik
jyanik
at
localnet
dot com

 

[William Sommerwerck]

Maybe the price difference is due to "new and improved"
rather than any other reason.

No, eutectic solder has always been more expensive, and the reason has
always been that tin is more-expensive than lead.

63/37 has the lowest melt point of all tin/lead alloys, 361 F

Exactly. That was my point, and MCM's error. I remember the little phase
diagram in the Popular Electronics article.

 

[William Sommerwerck]

91% is what CVS sells. I don't recall the price, though.

Drug stores periodically have sales. You should be able to get a pint bottle
of 91% for less than a dollar. No point in the 75% stuff.

 

[David]

"Jim Yanik" <jyanik@abuse.gov> wrote in message
news:Xns9DB76443FE679jyaniklocalnetcom@216.168.3.44...

"William Sommerwerck" <grizzledgeezer@comcast.net> wrote
in
news:i1p4j1$t6b$1@news.eternal-september.org:

Rosin flux can be removed with 99% isopropyl alcohol
($1 a bottle at your corner drug store).

You won't find 99% for $1. (91%, maybe.)




91% is what CVS sells,I don't recall the price,though.

--
Jim Yanik

The Meijer store here in Illinois has 99% isopropyl. It is
normally about $1.25 for a 16 oz. bottle but occasionally
they run sales of 2 for 1 at that same price. I stocked up
with about a dozen bottles the last time they ran that sale.
I avoid the lower % stuff because it is not always diluted
with just water but sometimes oils and skin lotions. These
are to be avoided for electronics work.

David

 

[William Sommerwerck]

I avoid the lower % stuff because it is not always diluted
with just water but sometimes oils and skin lotions.
These are to be avoided for electronics work.

This is usually labelled "rubbing alcohol".

 

[Jeff Liebermann]

On Thu, 15 Jul 2010 10:31:05 -0700, "Robbie Hatley"
<see.my.sig@for.my.contact.info> wrote:

Rosin flux can be removed with 99pct isopropyl alcohol ($1 a bottle at your
corner drug store).

I prefer the hardware store stuff in the metal cans:
<http://www.acehardware.com/product/index.jsp?productId=3958489>
More expensive but always 99% (ignoring what moisture it absorbs from
the air).

But frankly, I recommend NOT removing the rosin flux
scum. Leave it on; it's inert, airproof, waterproof, sweatproof, so it protects
the joint.

I have some rolls of solder around the shop that are not well labeled
or identified. Rather than risk leaving corrosive flux on a board, I
prefer to clean most everything.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[GregS]

In article <i1ovm1$ccb$1@news.eternal-september.org>, "William Sommerwerck" <grizzledgeezer@comcast.net> wrote:

The only reason 60/40 was ever manufactured in the first place is
that tin is more expensive than lead, so 63/37 solder costs more.

Cite, please? (and I don't mean a link to commodity prices)

I can only cite "common sense". 63/37 has always been
more-expensive than 60/40.

Then you can't substantiate your contention that 60/40 was THE
worldwide standard for tens of years just because it was a few pennies
cheaper per pound? That is the statement of yours with which I take issue.

I have no objection to your objection.

However, 60/40 was never, ever, "a few pennies per pound" cheaper than
63/37. For the last 30 years, the price of eutectic solder has been
sufficiently higher to make one think twice before buying it. The last time
I purchased solder, I decided that a one-pound roll of Kester 44 would last
the rest of my life, and I splurged. (At this point in my life, my
prediction is coming true. I rarely solder any more. If I drop dead, someone
digging through the junk will find a pleasant surprise. Assuming they know
what 63/37 is.)

I just checked Parts Express, and a 1# roll of Kester 44 60/40 is $22.23.
63/37 is $26.85. That's a $4.62 difference, almost 21% more -- hardly
"pennies per pound". When I bought the same product some years back, my
memory is that the price was around $7.50 for the 60/40, $9 for the 63/37.
Even that wasn't "pennies per pound".

I looked at the MCM site for Ersin products. Get this... MCM describes its
house brand of 60/40 solder as "provid[ing] the lowest possible melting
point".

Businesses almost always try to cut every corner they can. If you think your
solderers -- or soldering machines -- are doing a good job, you might prefer
to buy the less-expensive 60/40.

When I worked at Bendix Field Engineering, I often walked through the
section where a bunch of women (never men) soldered assemblies, following
NASA standards. I never thought to ask whether they used 60/40 or 63/37.

I like 63/37 because some stuff I do I like it as low a temp as possible.

Deja vu. I worked for BFEC at NASA site, and went to NASA ssoldering school.
I would guess 60/40 would be the norm.

greg

 

[Jeff Liebermann]

On Thu, 15 Jul 2010 13:06:03 -0700, dplatt@radagast.org (Dave Platt)
wrote:

Why are there these two very similar solders? Is there any situation
where one is better than the other?

I understand the eutectic nature of 63/37, and I wonder if/when 60/40
might ever be better to use.

My understanding is that 60/40 has somewhat better wetting properties
than 63/37, at least with some contact materials. Some people prefer
it for that reason.

63/37 makes a sharp transition between liquid state and solid state at
a single, well-defined temperature. 60/40 goes through a transition
between these two states over a significant range of temperature - in
between the fully-solid and fully-liquid states it can have a somewhat
mushy texture. Some people feel that 60/40 brings with it a somewhat
higher risk of creating a "cold" solder joint (inadequate fusion with
the contact surfaces) if the joint is moved or stress while the solder
is dropping through its mushy-state temperature region.

True. 60/40 goes through a semi-molten, plastic-like state, while
63/37 goes instantly from liquid to solid. The joint is not
mechanically solid in this plastic state. It's not an issue with tiny
components, that cool down rather rapidly. However, large components,
that retain more heat, can product "cold" solder joints if moved while
in the is plastic state.

In some cases, this plastic state is desireable. For example,
pre-RoHS plumbers solder was 50/50 for both low cost and the ability
to remain workable over a wider range of temperatures.
<http://www.chemguide.co.uk/physical/phaseeqia/snpb.html>

<http://en.wikipedia.org/wiki/Solder>
This got my attention:
Some alloys, namely of lead and to some degree tin, contain small
but significant amounts of radioisotope impurities. The
radioisotopes undergoing alpha decay are a concern due to their
tendency to cause soft errors. Polonium-210 is especially
problematic; lead-210 beta decays to bismuth-210 which then beta
decays to polonium-210, an intense emitter of alpha particles.
Uranium-238 and thorium-232 are other significant contaminants of
lead containing alloys.
Oh swell.... something else to worry about.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[William Sommerwerck]

I like 63/37 because some stuff I do I like it as low a temp
as possible.

Allmost all my soldering is repairs; cold joints seem more likely when
you're fixing something.

Deja vu. I worked for BFEC at NASA site, and went to NASA
soldering school. I would guess 60/40 would be the norm.

Probably. I never had to solder, so I never went to school.

Which site? When? I worked from 1974 through 1978.

 

[George Herold]

On Jul 15, 3:40 pm, zekfr...@zekfrivolous.com (GregS) wrote:

In article <7a307a68-f754-413e-8113-4b9d0ce7a...@c10g2000yqi.googlegroups..com>, George Herold <ggher...@gmail.com> wrote:





On Jul 15, 11:42=A0am, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On 15 Jul 2010 08:04:55 GMT, John Doe <j...@usenetlove.invalid> wrote:

none given.now (Joe) wrote:

Why are there these two very similar solders? =A0Is there any
situation where one is better than the other? =A0

Dunno, but... If you do detail work, try water-soluble flux
solder. You just wipe off the residue for a sparkling clean
circuit.

And one that makes a great humidity sensor.

John

Yeah, My prototype of a board with several high meg resistors (up to 1
gig.) was put together by myself with old Kester "44" (rosin flux.)
Worked great.  Production did a few with their favorite water based
flux... No good!  Now I have to convince them to go back to the old
standard.   The new ROHS fluxes seem to be even worse.  I measured a
few meg ohms between pads that had been 'cleaned'.... NOT.

I had a lot of problems with high Z circuitry. Got under the pads.
Some boards I had to clean/dry 10 times. In the interim, some of the cleaner
I used got into some caps and started their own circuit mess.

greg- Hide quoted text -

- Show quoted text -

What kind of flux were you using? I want to try some tests, just
laying down solder and flux gobs on 0805 SMD pads and measure the
resistance. Then cleaning and remeasuring. (I've got a bunch of
other 'fires' that I'm putting out so this may be a few days.)

George H.

 

[GregS]

In article <6737aa54-c264-4d4f-8dbf-86db5a76ba1f@q22g2000yqm.googlegroups.com>, George Herold <ggherold@gmail.com> wrote:

On Jul 15, 3:40=A0pm, zekfr...@zekfrivolous.com (GregS) wrote:
In article <7a307a68-f754-413e-8113-4b9d0ce7a...@c10g2000yqi.googlegroups=
..com>, George Herold <ggher...@gmail.com> wrote:





On Jul 15, 11:42=3DA0am, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On 15 Jul 2010 08:04:55 GMT, John Doe <j...@usenetlove.invalid> wrote:

none given.now (Joe) wrote:

Why are there these two very similar solders? =3DA0Is there any
situation where one is better than the other? =3DA0

Dunno, but... If you do detail work, try water-soluble flux
solder. You just wipe off the residue for a sparkling clean
circuit.

And one that makes a great humidity sensor.

John

Yeah, My prototype of a board with several high meg resistors (up to 1
gig.) was put together by myself with old Kester "44" (rosin flux.)
Worked great. =A0Production did a few with their favorite water based
flux... No good! =A0Now I have to convince them to go back to the old
standard. =A0 The new ROHS fluxes seem to be even worse. =A0I measured a
few meg ohms between pads that had been 'cleaned'.... NOT.

I had a lot of problems with high Z circuitry. Got under the pads.
Some boards I had to clean/dry 10 times. In the interim, some of the clea=
ner
I used got into some caps and started their own circuit mess.

greg- Hide quoted text -

- Show quoted text -

What kind of flux were you using? I want to try some tests, just
laying down solder and flux gobs on 0805 SMD pads and measure the
resistance. Then cleaning and remeasuring. (I've got a bunch of
other 'fires' that I'm putting out so this may be a few days.)

The boards were commercially made with water based flux.
I had to fix them. They actually laid out the boards, which was a mistake.

greg

 

[GregS]

In article <i1q2fa$nr9$1@news.eternal-september.org>, "William Sommerwerck" <grizzledgeezer@comcast.net> wrote:

I like 63/37 because some stuff I do I like it as low a temp
as possible.

Allmost all my soldering is repairs; cold joints seem more likely when
you're fixing something.


Deja vu. I worked for BFEC at NASA site, and went to NASA
soldering school. I would guess 60/40 would be the norm.

Probably. I never had to solder, so I never went to school.

Which site? When? I worked from 1974 through 1978.

http://zekfrivolous.com/goldstone/

 

[Fred Abse]

On Thu, 15 Jul 2010 23:53:31 -0700, William Sommerwerck wrote:

When I worked at Bendix Field Engineering, I often walked through the
section where a bunch of women (never men) soldered assemblies, following
NASA standards. I never thought to ask whether they used 60/40 or 63/37.

NASA standards authorize both.

--
"For a successful technology, reality must take precedence
over public relations, for nature cannot be fooled."
(Richard Feynman)

 

[William Sommerwerck]

Which site? When? I worked from 1974 through 1977.

http://zekfrivolous.com/goldstone

Did you ever change the klystron frequency from the control panel (there
were six buttons along the bottom), rather than going out to the
transmitter? If so, you used one of the improvements I installed.

 

[Robbie Hatley]

"GregS" recommends for flux removal:

If you can get 95% ethanol, I thinks its best. By the time
you use 98 or 99% it absorbs water anyway on the board,
and you still have a water residue. You can also drink it.

And then you accidentally plug the 120VAC into the 5VDC output of
a voltage regulator, which promptly explodes and emits flames and
smoke, and you just have time to say "oh wow, man, pretty fireworks"
before the lights go out and the boss comes storming in saying "What the
hell is going on in here? Why is that circuit board flaming like that?
Someone grab the fire extinguisher!" Yep, ethanol works wonders,
but it's probably not best for job security. I think I'll stick with the
isopropanol.

 

[GregS]

In article <i1qa75$p2m$1@news.eternal-september.org>, "William Sommerwerck" <grizzledgeezer@comcast.net> wrote:

Which site? When? I worked from 1974 through 1977.

http://zekfrivolous.com/goldstone

Did you ever change the klystron frequency from the control panel (there
were six buttons along the bottom), rather than going out to the
transmitter? If so, you used one of the improvements I installed.

I never ran that, but do recall them tuning them up. Something
rings a bell though about mods. As the 80's rolled through everything
was remote controled off site.

I do remember the time I pushed a button on one of the antenna motors,
and everything went black for miles.

I also remember the time one would go outside and point at the falling Skylab,
and the other person would try to move the antenna and lock on to it.
What with the 1 degree beamwidth was impossible. We were using Norads
predicts and they were too far off to be able to use. Somebody finally locked
onto the spacecraft and finally got good predicts.

I also remember the time we tracked the moon with a wrench.
For a while.

Big 85 ft.antenna made in Pittsburgh, as was much of the stuff made in the USA
back then.


greg

 

[Michael A. Terrell]

Jeff Liebermann wrote:

On Thu, 15 Jul 2010 10:31:05 -0700, "Robbie Hatley"
see.my.sig@for.my.contact.info> wrote:

Rosin flux can be removed with 99pct isopropyl alcohol ($1 a bottle at your
corner drug store).

I prefer the hardware store stuff in the metal cans:
http://www.acehardware.com/product/index.jsp?productId=3958489
More expensive but always 99% (ignoring what moisture it absorbs from
the air).

But frankly, I recommend NOT removing the rosin flux
scum. Leave it on; it's inert, airproof, waterproof, sweatproof, so it protects
the joint.

I have some rolls of solder around the shop that are not well labeled
or identified. Rather than risk leaving corrosive flux on a board, I
prefer to clean most everything.

I just tossed solder like that into my solder pot.

--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.

 

[David Eather]

On 16/07/2010 7:35 AM, Jim Yanik wrote:

"William Sommerwerck"<grizzledgeezer@comcast.net> wrote in
news:i1nqh7$7qt$1@news.eternal-september.org:

Because it is a eutectic mixture, 63/37 does not have "much
of a plastic state". This means it is more [sic] sensitive to
movement in the joint while the solder is cooling -- if the
connections are unstable it forms more [sic] dry joints.

I don't what you meant to say, but what you did say is backwards.
Eutectic solder is less likely to produce a dry or crystallized joint.




I agree;
the eutectic joint solidifies faster and thus less likely to move while the
solder is still "plastic".

When the joint moves while in the plastic stage it is still electrically
connected - when the joint moves with a eutectic mixture it cracks - the
joint is very weak when still close to the liquid stage. With the non
eutectic mixture the crystals of tin provide strength while the solid is
cooling.

I might not have explained it very well, but I assure you, with total
honesty, that the reason 60/40 was popular was the better reliability
for point to point soldering and the reason 63/37 is now taking its
place is that point to point has all but disappeared and the eutectic
mixture gives slightly lower thermal stress.

Either that, or you believe or antecedents were morons, who while they
knew about the eutectic mixture, were too stupid to use i,t or too
clumsy to mix it, or they thought a few dollars extra per ton of solder
was too much to pay for the good stuff.