Hi,

 The No Etchback sounds correct.

 Does anyone have a cross section image that shows etch back. I would be interested in comparing the two images.

Thanks,
Bob K.

-----Original Message-----
From: TechNet <[log in to unmask]> On Behalf Of Wayne Showers
Sent: Thursday, April 19, 2018 10:11 AM
To: [log in to unmask]
Subject: Re: [TN] R: [TN] R: [TN] PCB failure

The real problem is that this PCB has no etchback, positive or negative (PCBs are defective).  As far as resin recession, yes the processing probably caused the separation, but once again, the PCB has no etchback.

I would send that cross-section image to the PCB supplier and asked them if this is typical.  I suspect that they will realize it is a trap and either offer a crazy answer or admit that their is no etchback and offer to re-run/replace the PCBs.