It may be possible, but I think there are two things to 
consider:

1. In the time between soldering and cleaning, does the
older flux harden to the extent that it becomes difficult
to clean?

2. Are the flux types in the sequential steps all 
compatible?  You don't want to mix water soluble residues
with rosin, for example, because you may end up with a
highly reactive residue that is difficult to remove.  Better
to clean off the reactive residues before they become mixed
with something else.

-Joe

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Ioan Tempea
Sent: Tuesday, March 16, 2010 10:06 AM
To: [log in to unmask]
Subject: [TN] Eliminating interemediate washes

Dear Technos,

 

Is it doable to wash a mixed technology board ( SMT + TH) only at the end of TH?

 

I mean instead of repeatedly washing (SMT first side-wash, SMT second side-wash, TH-wash, manual soldering-wash) adopting a one wash strategy (SMT first side-no wash, SMT second side-no-wash, TH-no wash, manual soldering-wash). TH might not be done in the same day as SMT, but no later than next day and boards washed within 3 hours after wave soldering.

 

Is anybody in the industry doing this?

 

Pros and cons?

 

Thanks,

 

Ioan Tempea, ing.
Ingénieur Principal de Fabrication / Senior Manufacturing Engineer T | 450.967.7100 ext.244 E | [log in to unmask] <mailto:[log in to unmask]> W | www.digico.cc <http://www.digico.cc/> 

 
 N'imprimer que si nécessaire - Print only if you must

 


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