>> Equating CEM-3 and FR4 is not encouraging as the two are fundamentally
>> different in layup PLUS use different chemistry resins.
>> I posted a longish post a few months back covering matters related to
>> different PCB materials and characteristics. It included some references=
 and
>> may be worth looking at. I've just reposted it under subject line Re: [E=
E];
>> PCB Materials (was Parallel passives and sprinkled vias?)
>
> Everything I've seen, dozens of boards from Gold Phoenix in the last
> couple years has been what appears to be real FR-4.
> I've not noticed any copper pull-up problems on boards that are gently
> reworked a couple times. When you start getting into higher
> temperatures, larger parts, larger holes, there are always issues with
> reworking too much.

Good to hear re GP.
Interestingly, he notes that PCB's from Eurocircuits do not have the
same problem.
Murphy says that there may be relevant missing information but it does
sound from what's said that E' do something differently.


      Russell
--=20
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