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Matt (Staff) - 9/24/2018 9:18:34 AM

Sorry to come into this late but I have ready through the thread. Warren is off at the moment so I'm checking in on some support threads. ZEBAS I think the way forward here is to simplify what's being tested, isolating as much as possible.

The conclusion that you have come to regarding cure inhibition caused by different brands of cured epoxy substrate seems highly unlikely but could be tested for in a controlled way by making up some small samples:

1. I would make up 4  petri-dish sized samples (ideally in an inert thermoplastic container, such a polyproylene) with accurately weighed and mixed XCR, EL2 and the MGS L285+H286 at a 2mm depth in the bottom of each. One sample with no resin in (making up the four samples).
2. Cure all resins off fully in the same environment (a temperature controlled oven at 20°C would be ideal).
3. Make sure the samples should be fully cured (according to their datasheets, with respect to their cure time/temperature).
4. Key the surface of the three samples and then pour a 1mm coating of correctly measured and mixed XCR over the top of the three cured and keyed resin samples and into the remaining empty dish.
5. Cure all samples together back in the 20°C oven until fully cured.

I believe this would quite quickly provide results that would give a good indication as to whether there is any substance to your suspicions and, as unlikely as it seems to me, I would certainly be happy to remain open-minded and investigate further if you do find a difference across the samples. For the results to be genuinely helpful though it would be essential that the mix ratios were correct (helpful if you give us the actual grams used) and that the cure state was complete for all resins. Before they reach full cure there is the potential for a reaction which could more plausibly inhibit or affect the cure of a resin applied over the top.

I hope this helps and look forward to working with you to get to the bottom of this.