OK, I've had a good look at the P. Kay MS2. Framnkly, I see no grounds
for sufficient originality for a patent to be granted. Let me go into
the history of solder blankets. The original one was vegetable oil,
usually peanut oil. This was effective at reducing dross formation and
the acid decomposition products actually chemically reduced some of the
dross back to metal. Two disadvantages: flammability and odour, which
rendered it unpopular. Also, it had a short lifetime because of
polymerisation, requiring skimming twice/day.
To overcome this, van t'Hoen helped develop a mineral soldering oil
which was marketed as Shell Peblum A, initially for the tinplate market
and later for soldering. This was a pure blanket product with no
chemical reduction. It had a reasonable lifetime of a few days.
Then came the most significant development in the 1960s, by the
erstwhile London Chemical Company in Bensenville, IL (later taken over
by Alpha Metals). This was marketed as Lonco Fusecote 240. This was a
blend of carboxyl alkanes and their polymers. This was popular for
immersion reflow of electroplated tin/lead alloys, as well as being a
clean substitute for soldering oils. It was easily cleaned with either
water or the usual organic solvents. It was very stable with waves up to
~245°C and was safe with a flash point of ~265°C. Typical lifetime was
about one week. Some of the components of this had surfactant properties.
A different technique was offered by Fry's Metals, in Mitcham. They
offered orange tablets of a hard wax blended with a reducing agent. This
looked like a chocolate bar and I suspect that this was a deliberate
ploy as there was also a chocolate company called Fry's. The two
companies were founded independently by two branches of the same Quaker
family in the 19th c. A small piece of the wax floated on a drossy
solder bath reduced the volume of dross and some of the metal was
recovered. The gunge resulting from this was then skimmed off, but the
technique left no or little blanket.
Other techniques used for static baths was floating pine sawdust on the
solder. This was actually quite good at reducing dross by means of the
slow exudation of rosin.
As for machinery, the most significant was the Hollis machine which
sucked a small volume of the "oil" and mixed it into the solder at the
bottom of the wave, which did not oxidise. The disadvantage was that
micro-droplets of oil were sometimes found in solder joints. This did
not appear to affect the reliability but did cause some worry. Other
manufacturers just offered an oil blanket so the wave itself was
unprotected. Another technique was to drop a few drops of oil across the
wave as each pallet or circuit approached it. Fry's recommended
occasionally rubbing their orange "chocolate" along the nozzles with the
wave off, of course.
One of the most important factors to consider is the "cleanability" of
the oil residues on the assembly. The vegetable and mineral oils
required solvent cleaning, while Fusecote, being water-soluble, could
also be water-cleaned, but was prone to foaming and additions of octylic
alcohol and soft soap were required in the wash water.
The P.Kay MS2 appears to be quite similar to Fusecote in all ways,
except that it has a higher flash point, possibly because of longer
chain alkane molecules. I have little doubt it is effective. What
worries me is the toxicity to water wildlife and the long lifetime. This
suggests (my speculation) that it may contain nonyl- or
deca-phenoxylates or something similar which are non-ionic detergents
that are not looked on too kindly in waste water by some authorities. If
so, this may require the need for elimination before emission into a
waste water stream.
Hope this helps.
Brian
Chris Schaefer wrote:
> Hello all,
>
> Has anyone within these walls used the newer flavors of solder surfactants
> or is considering using them in their solder pots for wave? Since the cost
> of Lead Free solder is so high and the dross production will be
> significantly greater, we have been considering the use of this material to
> reduce dross production thus reducing costs. There is a brand name called
> MS2 technologies which is distributed through or made by PK Metals. There
> is a material for Pb free soldering and Pb soldering depending on what you
> are using. I have ordered some of this liquid material to determine the
> effect it has on dross production and other components of flow soldering
> (i.e. joint integrity, affects on the metals inside the solder pot,
> increased or decreased wetting ability, and quite a few more components).
>
> So if anyone has some insight into the new solder surfactants, I would
> appreciate you help and guidance.
>
> Thank You in advance and hope you all have a great weekend. I know I will
> (maybe... hmmmm!) because I am proposing to my girlfriend this weekend -
> hopefully she say's yes - I need all of you prayers ha ha! Chow!
>
> Chris Schaefer
> Suntron Corporation
> Process Engineer
> 540 N. Rogers Road
> Olathe, Kansas 66062
> 913.393.5878
> [log in to unmask]
>
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