Trinidad Pro applied over International self polishing

[B4A]

I want to replace my current anti-fouling (International Interspeed 6400NA - a TBT free, controlled depletion polymer (CDP) self polishing antifouling system) with Trinidad Pro (a hard, high cuprous oxide loaded paint.

Should I use a primer or a barrier coat after I remove the old anti-fauling?

[tkeithlu]

B4A, I think that you need to consult the Trinidad people on this question. Surface preparation for bottom paint is really tricky, and the cost of failure to adhere is really high. They may very well tell you to sand off all the International paint, while not collecting $200 or passing go. Well meant advice from people with similar situations, unless it is to say sand it all off, is one of those "advice is free, the consequences of taking advice is your problem" situations.

Good luck with it.

[Tusitala]

we were using Trinidad on our Tri, it's really good stuff. I tried a few different approaches to coating with it, some went over International Interprotect, some went over Pettit Protect and some areas were applied directly over well sanded and prepped epoxy. Sorry to say the areas that were not primed did not adhere. Now I know some people that have had great luck with both antifoul and topcoats put down directly on sanded and prepped epoxy but since it hasn't been my experience I now always prime.

Pat

[Bill O]

Not trying to be funny here, but what do the instructions tell you to do?

Were you able to sand down to bare f/g? Follow the instructions for bare hull (probably need a primer).
Do you need a barrier coat due to blisters?
Only other suggestion would be to hot coat the Trinidad into the primer so it sticks better.

[fstbttms]

Originally Posted by B4A

Should I use a primer or a barrier coat after I remove the old anti-fauling?

Yes.

Interspeed 6400 should always be applied over a recommended primer coating scheme. The primer surface should be dry and free from all contamination. Interspeed 6400 must be applied within the overcoating intervals specified for the primer (consult the relevant primer data sheet).
Areas of breakdown, damage etc., should be prepared to the specified standard e.g. Sa2½ (ISO 8501-1:2007)) and primed prior to the application of Interspeed 6400.

https://marinecoatings.brand.akzonob...4_20160418.pdf