Yes, this is correct, old paste looks good, but it doesn't work well,
as noted below.

My first experience with solder paste was using a 'sample' from EFD.
They give you an enormous tube of it-way more than any 'normal'
non-industrial user needs for a year or more. When it begins to show
signs of not working well, fill the ultrasonic bath with tap water,
and drop the syringe in-needle and all. I used that sample from EFD
for 8 years, with no special treatment other than the ultrasonic bath
from time to time.

As far as I know, EFD still offers teh same enormous sized 'sample'
for free, although I haven't re-ordered yet.

Enjoy.

Art

>> Basically, the stuff comes from the tube as
>> thousands of tiny little balls.
> ...
>
> This happened to me too (I could see the little balls using a 20x jewellery
> loupe), however, I knew the paste was relatively old. When it was new it
> made a perfect job though, so your paste might has just gone or the quality
> might not so good. I've read somewhere that it is possible to "renew" solder
> paste using an ultrasonic cleaner, so they put the synergy in it (without
> water) and then the ultrasonic sound mixes up the paste - not sure if I
> remember well the method and never even tried, however,  may worth to try it
> out once.
>
> Tamas
>
>
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