OT: Unknown Kester solder alloy

[Robert Baer]

Someone gave me a 4oz roll of Kester solder that is only marked ALLOY
95/5 with a blue label, diameter 0.031 in, net wt 4oz (1/4 lb).
There is no other useful info on the labels; maybe the color of the
label is the clue?
Kester cannot tell *which* alloy it is (Sn95Ag05 or Sn95Sb05)?
If they cannot tell which alloy it is, how can a customer know?

 

[Fred Bartoli]

Someone gave me a 4oz roll of Kester solder that is only marked ALLOY
95/5 with a blue label, diameter 0.031 in, net wt 4oz (1/4 lb).
There is no other useful info on the labels; maybe the color of the
label is the clue?
Kester cannot tell *which* alloy it is (Sn95Ag05 or Sn95Sb05)?
If they cannot tell which alloy it is, how can a customer know?

You can tell it from their melting temperature range:

http://www.kester.com/en-US/technical/alloy.aspx

How to test this now? I don't know

Well, maybe with a TC.
Melt a bit of it, the solder, not the TC , and let it cool slowly while
monitoring the temperature. You should have some plateau in the curve, owing
to the solidification latent heat.

 

[Glen Walpert]

Someone gave me a 4oz roll of Kester solder that is only marked ALLOY
95/5 with a blue label, diameter 0.031 in, net wt 4oz (1/4 lb).
There is no other useful info on the labels; maybe the color of the
label is the clue?
Kester cannot tell *which* alloy it is (Sn95Ag05 or Sn95Sb05)?
If they cannot tell which alloy it is, how can a customer know?

The easiest way to check is by melting temp range:
Sn95Sb05 - solidus 232 C liquidus 240 C
Sn95Ag5 - solidus 221 C liquidus 245 C

SnSbo5 is a standard alloy for plumbing usually available in larger
diameters as solid core, SnAg05 is a standard but not very common
electronic solder likely in smaller diameters and possibly with rosin
core.

 

[Joseph2k]

Someone gave me a 4oz roll of Kester solder that is only marked ALLOY
95/5 with a blue label, diameter 0.031 in, net wt 4oz (1/4 lb).
There is no other useful info on the labels; maybe the color of the
label is the clue?
Kester cannot tell *which* alloy it is (Sn95Ag05 or Sn95Sb05)?
If they cannot tell which alloy it is, how can a customer know?

Sounds like it may be 95Bi 05Sn (a lead free composition), not that Bismuth
is all that much less toxic.

 

[kell]

Someone gave me a 4oz roll of Kester solder that is only marked ALLOY
95/5 with a blue label, diameter 0.031 in, net wt 4oz (1/4 lb).
There is no other useful info on the labels; maybe the color of the
label is the clue?
Kester cannot tell *which* alloy it is (Sn95Ag05 or Sn95Sb05)?
If they cannot tell which alloy it is, how can a customer know?

Who took your phone call or answered your email? Some doofus that
didn't want to deal with it.

 

[Robert Baer]

You can tell it from their melting temperature range:

http://www.kester.com/en-US/technical/alloy.aspx

How to test this now? I don't know

Well, maybe with a TC.
Melt a bit of it, the solder, not the TC , and let it cool slowly while
monitoring the temperature. You should have some plateau in the curve, owing
to the solidification latent heat.

Hmmm.
Sn95Ag05 range 221-245C, Sn95Sb05 range 232-240C.
That is a lot of overlap...
Do you know enough about the plateus for a measurement to be
non-ambiguous?

 

[Robert Baer]

The easiest way to check is by melting temp range:
Sn95Sb05 - solidus 232 C liquidus 240 C
Sn95Ag5 - solidus 221 C liquidus 245 C

SnSbo5 is a standard alloy for plumbing usually available in larger
diameters as solid core, SnAg05 is a standard but not very common
electronic solder likely in smaller diameters and possibly with rosin
core.

Like i said, that is a lot of overlap; also Kester makes both with
fine diameters and flux cores.

 

[Robert Baer]

Robert Baer wrote:



Sounds like it may be 95Bi 05Sn (a lead free composition), not that Bismuth
is all that much less toxic.

AFAIK nobody makes solder with that wierd alloy.
Furthermore, Bismuth is so non-toxic that it is used in Pepto Bismol
and as a lead replacement in birdshot for environntmental considerations.

 

[Tim Williams]

Kester cannot tell *which* alloy it is (Sn95Ag05 or Sn95Sb05)?
If they cannot tell which alloy it is, how can a customer know?

Welllll, you can take hydrochloric acid, add some hydrogen peroxide (30% if
possible; 3% is practically water and isn't very useful) and dissolve a
sample. Silver doesn't dissolve, but antimony does, so if it is
silver-bearing, it will leave a precipitate.

Alternately, instead of adding H2O2 or waiting a long time, you can use a
few volts to dissolve it electrically. Cut a strip of solder, connect it to
+3V (current limited to say, 10A) and put it in half-diluted muriatic (HCl)
acid. Copper wire is fine for the cathode.

Tim

 

[Robert Baer]

Who took your phone call or answered your email? Some doofus that
didn't want to deal with it.

That would be Kester representative.
Their question was "is there any other information on the label?"
My answer was "no" which resulted in dead silence.
Seems to be poor salesmanship to have incomplete information on
product labels, especially when there are good possibilities of
confusion and more to the point contamination (where alloys or metal
content is rather important).

 

[Robert Baer]

Welllll, you can take hydrochloric acid, add some hydrogen peroxide (30% if
possible; 3% is practically water and isn't very useful) and dissolve a
sample. Silver doesn't dissolve, but antimony does, so if it is
silver-bearing, it will leave a precipitate.

Alternately, instead of adding H2O2 or waiting a long time, you can use a
few volts to dissolve it electrically. Cut a strip of solder, connect it to
+3V (current limited to say, 10A) and put it in half-diluted muriatic (HCl)
acid. Copper wire is fine for the cathode.

Tim

Far out!
Thanks.

 

[Glen Walpert]

Like i said, that is a lot of overlap; also Kester makes both with
fine diameters and flux cores.

11 C difference in solidus should be trivial to measure, melt a drop
on a thermocouple junction with hot air and observe the inflection
points on cooling rate. Cooling rate will be slower during
solidification; either between 240 and 232 or between 245 and 221.
Compare to a drop of known alloy if the results are not immediatly
clear. If you don't want to do it the easy way, post on
sci.engr.metallurgy and ask if there is a usable chemical spot test -
but don't expect the chemicals to be readily available.

 

[Joseph2k]

AFAIK nobody makes solder with that wierd alloy.
Furthermore, Bismuth is so non-toxic that it is used in Pepto Bismol
and as a lead replacement in birdshot for environntmental considerations.

Not the way my reference books read. There is no longer any Bismuth in
Pepto any more, it is a hardener in lead alloys (not a replacement for lead
because of cost issues).
Tin-Silver and Tin-Antimony alloys are both more plausible than [my guessed]
Bismuth-Tin though. Even though Bismuth has a conveniently low melting
point.

 

[John Popelish]

There is no longer any Bismuth in Pepto any more,

(snip)

(copied from the label of the Walmart generic competition for
Pepto-Bismol) Active ingredient, per tablespoon: Bismuth Subsalicylate
(262 mg)

See also:
http://www.pepto-bismol.com/liquid.shtml

 

[Jim Thompson]

(snip)

(copied from the label of the Walmart generic competition for
Pepto-Bismol) Active ingredient, per tablespoon: Bismuth Subsalicylate
(262 mg)

Gag! That stuff makes me barf.

See also:
http://www.pepto-bismol.com/liquid.shtml

If you get traveler's diarrhea try Imodium A-D. Then you'll pray for
diarrhea ;-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

"Don't mess with my toot toot!", Antoine 'Fats' Domino

 

[Robert Baer]

11 C difference in solidus should be trivial to measure, melt a drop
on a thermocouple junction with hot air and observe the inflection
points on cooling rate. Cooling rate will be slower during
solidification; either between 240 and 232 or between 245 and 221.
Compare to a drop of known alloy if the results are not immediatly
clear. If you don't want to do it the easy way, post on
sci.engr.metallurgy and ask if there is a usable chemical spot test -
but don't expect the chemicals to be readily available.

I do not have enough politicians to do that (no hot air).

 

[Michael A. Terrell]

I do not have enough politicians to do that (no hot air).

You don't need any politicians, JT has enough hot air to run a couple
reflow ovens.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

 

[Ancient_Hacker]

There used to be a MIL-spec that required some Antimony in MIL-spec
solder. This was due to a mostly-mistaken belief it helped keep the
Tin from changing into allotropic forms.

So you might have some MIUL-spec 95%Tin/5%Antimony solder here.!

BTW Antimony is not toxic in pure form. Just stay away from Antimony
Trioxide!

 

[Robert Baer]

Someone gave me a 4oz roll of Kester solder that is only marked ALLOY
95/5 with a blue label, diameter 0.031 in, net wt 4oz (1/4 lb).
There is no other useful info on the labels; maybe the color of the
label is the clue?
Kester cannot tell *which* alloy it is (Sn95Ag05 or Sn95Sb05)?
If they cannot tell which alloy it is, how can a customer know?

Finally found an "old timer" at Kester, and he determined the alloy
and age of the solder from the type and color of the label.
It is about 3 years old and is Sn95/Sb05.