Yes Please do Steve. The supplier I'm dealing with is customer mandated
and I have contacted our customer telling him the problems I am
experiencing and he has admitted to me if he audits him he would
probably fail but he supports us in any way he can. I say audit him and
look for another Supplier.
As far as the copper not having the same shine I thought maybe it had
contaminants from the plating process and therefore the masking wasn't
adhering. What do you think on this?
Thanks so much
Sue
-----Original Message-----
From: Steve Gregory [mailto:[log in to unmask]]
Sent: Monday, February 09, 2004 5:21 PM
To: [log in to unmask]
Subject: Re: [TN] Solder Mask Flaking
Hi again Sue!
Would you like me to post the pictures on my page so others can see
them? Just give me the word.
But looking at your pictures, your problems seems somewhat different
than mine. For one thing the exposed copper on your boards doesn't have
the same shine that the copper on my boards did.
Another thing I noticed, was that there was adhesion problems with the
solder mask from the beginning before hitting the wave, as evidenced by
the solder wetting out at places where solder mask should have been.
This was a liquid photo imagable solder mask wasn't it? There definately
was some sort of adhesion problem here, but I can't really say for sure
what caused it. One thing I can say with pretty good confidence, I find
it hard to say that it's something you've done in your process that has
caused the mask to fail like this.
I must say, this is the first time I've ever heard of fab vendor telling
a customer to lower their solder pot temperature so the mask doesn't
fall off, or saying that if you don't flux your boards enough the mask
might come off too...but maybe I'm missing something.
-Steve Gregory-
> Thanks Steve, Looks like I may have the same problem, I have attached
> pictures of my problem here. I am also forwarding this response to our
> supplier to see if he will cooperate more and answer me to this point.
> Sue
>
>
>
> -----Original Message-----
> From: Steve Gregory [mailto:[log in to unmask]]
> Sent: Monday, February 09, 2004 1:55 PM
> To: [log in to unmask]
> Subject: Re: [TN] Solder Mask Flaking
>
>
> Hi Sue!
>
> I had problems with solder mask a few weeks ago that I posted about.
> In my case, I was seeing it after cleaning. Also in my case it wasn't
> merely flaking, it was like a snake sheding its skin...mask was coming
> off in huge slabs. I still have some pictures of it on my web page at:
> http://www.stevezeva.homestead.com/
>
> Look at the "Mask Peel" pictures there...it was ugly! What it turned
> out to be was that the pumice scrub before mask application hadn't
> been done on one panel even though the production paperwork at the fab
> vendor had been signed off that had been done. This was a dry film
> solder mask over bare copper by the way...
>
> The problem only affected 2 boards because it was built in a 2-up
> panel. For some reason, only one panel out of the lot that got built
> didn't get scrubbed as it should have been. The boards passed our tape
> test at incoming inspection too. It wasn't until the boards got
> thermally shocked at wave solder, and then washed, did the poor
> adhesion because of the bad surface prep show itself.
>
> -Steve Gregory-
>
>
>
> > I know this was up for a discussion a few weeks ago. Can anyone tell
> > me what the root cause was determined to be?
> >
> > I am experiencing solder mask flaking on a group of boards
> > manufactured by one certain supplier. It is a random occurrence for
> > example 10 out of the 100 boards we had this occurr. Then a
> > different board we ran 8 out of 40 were flaking same supplier as
> > previous one.
> >
> > Supplier runs samples at his facility and he see's no flaking. We
> > changed our solder temperature from 500 degrees to 450 degrees at
> > the suppliers suggestion and flaking still occurs. He then states
> > maybe were not using enough flux but review shows plenty of flux if
> > anything
>
> > maybe were using to much flux from the way the boards look coming
> > out of the wave and washer.
> >
> > Thanks
> > Sue Foulkes
> > QA Manager
> > AESCO Mfg.
>
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to [log in to unmask]: SET
Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the
posts: send e-mail to [log in to unmask]: SET Technet Digest Search the
archives of previous posts at: http://listserv.ipc.org/archives Please
visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for
additional information, or contact Keach Sasamori at [log in to unmask] or
847-509-9700 ext.5315
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
-----------------------------------------------------
|
