Phil

You have brought up what is essentially an SME question and a good one, at that. I
don't know the specific mask you use but, being peelable, I'm assuming it is a
PVA/latex type in an aqueous base (possibly with a slightly ammoniacal odour?). The
choice of this kind of mask may be critical where "no-clean" techniques are practised.
I am not saying that your mask or any other specific makes are bad, but ***some*** of
them may leave dangerous levels of ionic contamination under some conditions of use. I
therefore recommend caution and qualification. Of course, if such masks are peeled off
before any form of cleaning using any aqueous technique, then these residues are very
effectively removed. If they are peeled off afterwards, beware (quite apart from the
accidental peeling in the cleaning machine clogging the filters!)!

When you emerge from the dark ages into the Renaissance, you may care to consider
soluble temporary solder masks, although they are not without some disadvantages as
well as great advantages. Again, you have to choose the one that best suits your
overall process.

Best regards

Brian

Phil Nutting wrote:

> Hi,
>
> We currently use Chemask CM8 for masking our through hole boards.  Our
> process uses rosin flux for hand solder and no clean alcohol based  flux in
> the wave solder system. At present we peel the mask off after wave solder.
> Post wave cleaning (after the non-waveable parts have been inserted) is by
> hand using alcohol.  We do not yet have an aqueous clean system.  Yes we are
> still working in the dark ages, but I'm working on that slowly.
>
> I'm interested to find out what other people use and why?
>
> Regards,
>
> Phil Nutting
> Manufacturing Engineer
> Kaiser Systems, Inc.
>
> ##############################################################
> TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
> ##############################################################
> To subscribe/unsubscribe, send a message to [log in to unmask] with following text in
> the body:
> To subscribe:   SUBSCRIBE TECHNET <your full name>
> To unsubscribe:   SIGNOFF TECHNET
> ##############################################################
> Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
> information.
> If you need assistance - contact Keach Sasamori at [log in to unmask] or
> 847-509-9700 ext.5315
> ##############################################################

##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in
the body:
To subscribe:   SUBSCRIBE TECHNET <your full name>
To unsubscribe:   SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Keach Sasamori at [log in to unmask] or
847-509-9700 ext.5315
##############################################################