In a message dated 8/13/99 6:30:07 PM Central Daylight Time,
[log in to unmask] writes:

> Hi all,
>    Just a few more wave soldering questions, I promise!!!
>  Here's my situation:
>  We (as a company) have been hand soldering 99.9% of our parts to PCA's
since
> 1954.  We make low volume, high mix military and space reliable assemblies.
>  We've recently purchased what we feel is a good, reliable wave soldering
> machine.  The problem is that only one or two individuals are familiar with
> wave soldering operations.  And one of them is not me!  Does anyone out
there
> know of any good references,texts, or classes on wave soldering as a
process
> that I can get/attend so that I know a little bit about what I am talking
> about?  It is hard to persuade an engineer with 30+ years of experience
that
> this is a good thing if you have only the vaguest notion of what you are
> talking about!
>
>  Thanks,
>
>
>  Eric Kalgren
>  BFGoodrich Aerospace
>  Data Systems Division
>  (505) 938-5139
>  [log in to unmask]

Hi Eric!

First let me say, that the fact that you come out and say that you've done
things one way all these years, and want to learn more is very relieving! I'm
a transplant from "Silicon Valley" into Tulsa, Oklahoma with a company that's
been doing things in the old "mil-spec-2000" way, and expect the same kinda'
"picture-perfect" results when you start to get into "Class-II" specs, or
when you start automating things...like with a wave solder machine.

As I probably don't have to tell you, there's so many variables that come
into play to keep you from achieving perfection...the perfect solder joint.
The joint that exhibits perfect qualities...perfect wetting, perfect shiny
surface conditions, and perfect volume...ahhh, if life were so easy! But as
we all know, that is a goal. What is reality, is that you can assemble a
product that will meet the expected life, and do it in a manner that will be
cost effective...in other words, make a few bucks along the way. Ain't that
why we all have jobs? To make a few bucks?

You can strive for perfection until you go broke...and that's the honest to
gods truth. That's one of the problems that I need to overcome where I'm at,
is that you've got to be realistic about things. The Wave Soldering process
is a very capable process that will give you very high quality solder joints
at a very cost effective means where your company can stay competitive and
make the money it needs to pay everybody's paycheck, but if you're looking
for the same visual quality of solder joints that you can get from a hand
solder operation, then it's gonna be a hard road to go...you can keep the
boards in a merry-go-round from final QA to rework forever if you want, but
the bottom line, is the bottom line...is it really necessary?

Not to make judgements about anything, but going through what I'm going thru
now, what I would've liked is for some people to go through some sort of
training where I'm at now before they went through any training about the
wave solder process, is the true nature of being competitive...how quality,
efficiency, and turn-around times have to be a concurrent goal, not one
before the other...

Does a solder joint that looks exactly like the pictures in the Martin
Marrieta pictures mean that it's a truely reliable solder joint? How many
times did it have to be touched-up and reheated to match that picture? Does
that matter? The problem that I see is that people from the "old school" (no
offense intended), get too hung-up on the cosmetics of things instead of
looking at the metallurgical aspects of what constitutes a reliable
joint...you can go broke making things look pretty...

Sorry I got up onna soapbox...pardon me...

-Steve Gregory-

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