I've never actually done this but here is something worth thinking
about. How about running a simulation using a small solder pot. Just
keep the proportion close to what the conditions are going to be in
the actual bath. Take a sample from the old solder, mix it with the
new stuff in appropriate proportion, run a few dummies or cheap
components on test coupons. Then look for drossing, increase new
solder concentration until you are satisfied with the results. You
might save  some money, but is it really worth the time?

Just an idea,

Alain Savard, B.Sc.
Chemical Process Analyst
CAE Electronics Ltd.
e-mail: [log in to unmask]

-----Original Message-----
From: Stephen R. Gregory [mailto:[log in to unmask]]

I'm gonna word this email very carefully, so I don't ruffle anybody's
feathers...
We're fixing to get a newer (used) wave solder machine to replace the tired
ol' Hollis we have now. The newer one is a Treiber with a 20" wide conveyer.
The guy we're getting it from asked me if I had plenty of bar solder on
hand,
because the pot holds 2200 lbs.!!! Holy-moly! Reminds me of Earl asking
about
how to empty a SEHO pot when the pot heaters went "kaput" on one of those
beasts they hold a ton of solder too...(by the way Earl, HOW did you do
that?)

But my question is; I'm gonna have to buy probably close to 1500 lbs or more
to charge the pot! Is there a problem mixing brands even though it's all
supposed to be 63/37? I have my favorite brand that I use, but it's a little
on the pricey side, and not too painful to management when I only get 250
lbs. every once inna while...

But I know someone up front is gonna crap their pants when I tell them we'll
need to buy over $4,000 of solder to fill the pot up! I know darn good and
well somebody is gonna ask if I can find some cheaper solder. I'd rather
stick with what I'm using now, it's the brand I've always used and I've
never
had any problems at all. But what if I mix brands? Tell me that I shouldn't
do that and give me some ammo...

-Steve Gregory-

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