Alberto,
I cannot claim to be an expert, but I believe the answer to your question is: "It depends"
The "goodness" or "badness" of any process will depend heavily on the constraints of your system, the product reliabilty level desired, finances, etc, etc, etc, ad nauseum.
Eric Kalgren
BFGoodrich Aerospace
Data Systems Division
[log in to unmask]
(505) 938-5139
>>> Alberto Callo <[log in to unmask]> 11/30/99 09:33AM >>>
So what process is better? No-clean, water soluble, etc?
Brian Ellis wrote:
>
> Dave
>
> As a pedant, I may go along with you on this, at least partially. I have used the
> term "no-clean" (always in inverted commas) for both material and process. "Low
> residue" is not necessarily the same, though. Many people use RMA with 25% or more
> solids as a "no-clean" and certainly the DIN F-SW32 fluxes, generally 15-30% solids,
>
> must be "no-clean" because you cannot clean them for love nor money. And no solder
> paste can be classed as low solids, as 50% or thereabouts of the stuff (by volume)
> is low-volatility chemistry. OK, the residues may be neatly transparent and matt, so
>
> you have difficulty seeing the residues but they are there.
>
> My personal definition of a "no-clean" flux/paste is one where the residues do not
> have to be removed for selected and qualified applications. A "no-clean" process is
> one where the post-soldering residues are not removed.
>
> Again, as a pedant, I think your message has revealed a requirement for a new
> terminology but, where there is already a firmly entrenched one, neither you nor I
> will ever budge it.
>
> Best regards
>
> Brian
>
> [log in to unmask] wrote:
>
> > Hi TechNet! Just to add a bit of wordsmithing to Brian's internet references.
> > The electronics community has created itself a technical "cultural" bias which
> > is going to take some time to undo. We have interchangeably used "no clean" to
> > describe both the material and process aspects of a product (e.g. flux). We
> > should be using the term "low residue" to describe the material characteristics
> > of a flux - how much flux residue is left on a printed assembly after soldering
> > processing. We should be using the term "no clean" to describe the process
> > characteristics of a flux - is it removable or non-removeable after solder
> > processing. The use of the term "no clean" for both the material and process
> > aspects is very confusing to the folks on the factory floor because they can
> > unintentionally misinterpret the product labeling as permission to no longer
> > clean an assembly which may not be the case. I also know very few process
> > engineers who are keen on having someone unfamiliar with their soldering process
> > to suggest that a "no clean" flux is ok. The description of "using a low
> > residue flux in a no clean process mode" leaves little room for
> > misinterpretation. Ok, enough soapboxing.
> >
> > Dave Hillman
> > Rockwell Collins
> > [log in to unmask]
> >
> > Brian Ellis <[log in to unmask]> on 11/27/99 02:21:23 AM
> >
> > Please respond to "TechNet E-Mail Forum." <[log in to unmask]>; Please respond to
> > Brian Ellis <[log in to unmask]>
> >
> > To: [log in to unmask]
> > cc:
> >
> > Subject: Re: [TN] Wave Soldering
> >
> > The United Nations Environment Programme Solvents Technical Options
> > Committee gives an excellent explanation, with the advantages and
> > disadvantages of each, in Chapter 2 of their 1998 Report to the Parties to
> > the Montreal Protocol. This 200 + page report can be downloaded (free) in
> > PDF format from the non-commercial committee site at
> > http://www.protonique.com/unepstoc
> > or you may purchase the printed document from
> > http://www.unep.org/ozone
> >
> > Brian
> >
> > Alberto Callo wrote:
> >
> > > Hi,
> > >
> > > I wonder if anyone can explain the difference between NO CLEAN and Water
> > > Soluble wave solder methods.
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