Hello All-
WOW !!! two postings from me in two days...

Here is the case:
We run a double sided reflow process.
We Print, Place, and Reflow the bottom of the boards..

Then

Print, paste, and reflow the top side.

Since the bottom side is mostly discrete and Resistor networks (unlike the
one pictured on Steve's Site) it works well.

For the through hole components we hand insert and solder them.


I just went down to the wave soldering room and found the
operator...........

Covering  the bottom side components  with removable masking material
(Chemtronics Brand) and sending the boards through wave.

Once Soldered...he removes the masking and all looks well.


Question(s);
1) Is this an acceptable practice?
2) What documentation is available to support or disclaim this?
3) What reliability issues are there due to any thermal mismatch?
4) Any leaching of masking material into the solder join causing poor joint
integrity?

Please advise,

Cal

P.s. Steve be a fountain; not a drain...keep up the excellent work

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