Has anyone else tried or used this technique? Let me know of a
better way if you have one. thanks.
Thomas, I've generally not needed the flux trick to get off burned
on dirt, per se, since I've not often had the problem of not being
able to get a stone clean enough except for those types, with no hole
behind a burnished in/flush set, where there's no way for flux to get
behind the stone either. But, i've found this VERY useful in
conjunction with laser welding, when you sometimes get a good deal of
black "smoke", from recondensed vaporized metal from the welding
process, coating nearby things, sometimes in areas you cann't reach.
Sometimes an hour or two in the ultrasonic still doesn't get it off,
but the flux sure does. I don't use Handy flux. Just lots and lots
(repeated applications) of batterns. You don't risk it burning away
as much, so the stones remain protectede better, I think. But if
this has worked for the black smoke from welding, I see no reason why
it wouldn't also be generally useful for your cases as well, as
you've found. The only trouble with your use is that sometimes,
since the stones also got hot enough to carbonize that dirt, the
stones too will be damaged, with a lesser polish or even bits and
pieces of the surfaces having become etched or frosted. No cleaning,
of course, can fix that.
One other trick you might try, either before your drastic means are
needed, just to also get the dirt off first, or afterwards, to get
the black off, is oven cleaner. We use the spray on type, with LOTS
of ventilation (It's mostly straight lye, with some surfactants
added, I think, so this is nasty stuff). Spray the ring, and enough
into a small container to then immerse the ring, and let THAT soak
for a while. Then try your ultrasonic and steam again...