Interprotect barrier coat concerns

[kito]

I applied my second to last coat of 2000e (white) before I start on the AF paint. I am kind of concerned about the speed the 2000e is drying. The last coat needs to pass the thumbprint test so to "hot coat" the first coat of AF. It was 65 and overcast this morning and the 2000e was already well pass the thumbprint test after just 25 minutes....no where near the time stated on the can. Anyone else experienced this too? I reck'n I need to roll 2000e in my right hand and AF in my left

 

[Ralph Johnstone]

I reck'n I need to roll 2000e in my right hand and AF in my left

I did mine back in 2001 and my notes show the same fast drying time and non sticking thumb test.

I completed applying the last coat of 2000e and then immediately started applying Micron CSC (ablative) in the same order as the 2000e went on. Scratched and picked at it after a few days and nothing was going to separate the CSC from the 2000e. That was all I was prepared to do and the first coat of CSC is still tightly adhered to the 2000e.

I would suggest another coat of 2000e to ensure you have a "green" coat and then quickly follow with your anti fouling (AF). One other thing would be to make the first coat of AF a different colour than the final coat of AF. Gives you warning when the AF is getting thin. My first coat is black and the later coats are eggshell blue.

 

[kito]

Thanks Ralph. Yea, those drying times are a joke. I have red and black Woolsey Yacht Shield SF. It is one of the few left that has Igarol (spl) and only $130 gallon at the time. I am debating to go black then red or visa versa. I wonder if one color does better than another

 

[Ralph Johnstone]

I wonder if one color does better than another

All sorts of theories abound as to whether dark or light is better. I'd do it scientifically and flip a coin .

 

[Charlie Jones s/v Tehani]

I use black- the porpoise seem to love it. The Interprotect is grey, so I can see when the paint is getting thin

 

[Gunni]

Kito;
I just did a Interprotect/ablative bottom paint job today and was able to apply the bottom paint in just over one hour - the 'thumbprint' test is the definitive call, not some numbers on the can. Those long wait hours are for the guys trying to get their bottom work done during cold spring weather, Interprotect two-part is really sensitive to air temperature.

 

[DougM]

If you are concerned about drying time, usually. You can increase the drying time by reducing the amount of catalyst somewhat, or increasing catalyst somewhat to accelerate drying time. You just cannot go to extremes. Percentage of mix on many epoxy like products changes depending on ambient temperature.
My experience with Interprotect was in reasonably mild weather, applied in early evening, low humidity, and it was at the thumbprint stage the next morning. Vc17 over the 2000 adhered perfectly. Just lucky I suppose.

 

[kito]

I will be adjusting my catalyst for my last coat I guess. Maybe go 4:1. The 3:1 just isn't cutting it. Like I mentioned, it was around 65 and overcast with low humidity. I am not sure how I can pass the thumbprint test the next morning......I had only15-20 minutes! I was thinking of doing one side at a time but would rather not. It takes me maybe 30 minutes to paint the bottom if I work fast. Hopefully going 4:1 will give me the time I need. Wondering now if I got a bad batch of the part B catalyst...............

 

[fstbttms]

I am debating to go black then red or visa versa. I wonder if one color does better than another

All sorts of theories abound as to whether dark or light is better. I'd do it scientifically and flip a coin .

If 25,000 hull cleanings experience is worth anything, I have never found one color to offer better anti fouling performance than any other, for a given product line.

 

[Ralph Johnstone]

I will be adjusting my catalyst for my last coat I guess. Maybe go 4:1. The 3:1 just isn't cutting it.

I don't think that'll work as hoped. The reactor in the mix is a component of the 2000e epoxy, not a catalyst. As such, you cannot vary the amount of the reactor same as you can the catalyst (methyl ethyl ketone) in polyester resin.

You'll wind up with an unpleasant goo of unreacted epoxy.

If you're that worried about the thumb test, any chance of waiting for some cooler weather, applying a coat of 2000e and the AF coat ? I did my AF application when the thumb test was pretty hard. No problem when I tried to scour off the AF with a rag the next time it was due for bottom paint. The final thickness of black ablative AF was NOT coming off the 2000e for love nor money.

 

[kito]

Thanks Ralph. I guess I will apply it at the crack of dawn when it's cooler. That "mix only what can be used in 5 hours" is insane. I mixed a quart at a time, enough to cover one side. By the time I got to the rudder, it was pretty much a thick goo. Maybe I am just not understanding this "thumbprint" test. After 20 minutes I can press my thumb on it where it leaves a print but doesn't leave any paint on my thumb. Maybe I need to whack my thumb with a 5 pound sledge hammer to make the 3-7 hour window that Interlux suggests

 

[Ralph Johnstone]

Maybe I need to whack my thumb with a 5 pound sledge hammer to make the 3-7 hour window that Interlux suggests

That's what we like to see ................... dedication .

Any chance of getting extra help on the application or have they all buggered off with my crew now that there's work to be done ?