I don't see anything for edge delam, there.
End use - part of power supply for communications equip.
Some delam goes into traces, some goes fully past vias - the board is small and densely featured. Many delam areas have components mounted on the top side of the board. They aren't spread so bad that you can really see into it to shoot some epoxy easily. I know the vias and/or internal trace areas are probably unsalvageable, but if it isn't into an area with an internal trace or via, and there are components over the area, do you need to rework them, and if so, how?
Steve - could you post a few pics? Just a few examples.
Steve Gregory <[log in to unmask]> wrote:
Hi Pearl!
Just how bad is the delamination? What is the end use of these boards?
If the delam goes into traces, that may be problematic, but not the end
of the world. If it's just base board material, that can usually be
repaired fairly easily. It's just a matter of getting some good two-part
epoxy (I use Loctite 0151), and patching everything together.
Here's a link for some good guidelines for base board repair:
http://www.circuitrework.com/guides/3-0.shtml
I feel your pain when it comes to re-scoring boards that haven't been
scored deep enough and have been already built. I've been there and done
that and even got a tee-shirt. It ain't no fun, but I don't have to tell
you that. Sometimes you have to do what you gotta do.
I found that when you have to go back and make the score deeper with an
exacto knife, patience is key. You have to understand that it's going to
take some time. You need to go over the existing score, scores and
scores of times (pun intended). It's better to go over the score with
your knife many times lightly, rather than trying to make deep cuts,
because it's then when your knife comes out of the score line and goes
into nearby traces. You also need to go over the score from both sides
of the board, not just one side.
Good luck!
-Steve Gregory-
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of pearl petras
Sent: Monday, November 06, 2006 11:37 AM
To: [log in to unmask]
Subject: [TN] Delam from separating boards
We had some v-scored boards, with components so close to the edge that
we could not use a depanelizer to separate them. (I know, I know, root
cause - no DFM)
On top of that, the V-score done was basically just a lightly etched
line.
Some enterprising people used some exacto blades to try to score them
further, and then just applied brute strength...
I have been told that most delam is non-repairable. Is that so? We
have an extremely high percentage of a build that will need to be
written off, if so.
If not, any thoughts on where to go for tips and tricks on how to
repair?
How do you determine what is repairable and what is not?
Switching away from RoHS to other headaches for a bit...
Thanks in advance.
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