Primocon over antifoul not drying

[webcraft]

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I needed to prime areas of the rudder that have been repaired (glassfibre). Reading up on primocon I saw that it could be used as a tie-coat between different antifouls, so decided to paint the whole rudder. I was expecting it to be dry in a few hours.

The bit over the fibreglass seems fine, but the primocon on top of old antifoul is soft (fingernail leaves an impression) and some of the antifoul underneath is sticky.

Anyone else had any experience of this? Will it harden eventually?


- W

 

[johnalison]

Odd. Never happened to me and I used it regularly for touching up before I had the lot stripped.

 

[chrishscorp]

I know its June allegedly but how warm and damp is it where you are ?

 

[Cactus Sailing]

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I needed to prime areas of the rudder that have been repaired (glassfibre). Reading up on primocon I saw that it could be used as a tie-coat between different antifouls, so decided to paint the whole rudder. I was expecting it to be dry in a few hours.

The bit over the fibreglass seems fine, but the primocon on top of old antifoul is soft (fingernail leaves an impression) and some of the antifoul underneath is sticky.

Anyone else had any experience of this? Will it harden eventually?


- W

have you checked compatibility, i read somewhere when i was doing mine that some anti-fouling does not agree with it.

i did mine earlier this year after getting rid of some rust spots on the keel and it dried pretty darn quick although i left it the full 24 hours as recommended in the leaflet before anti-fouling.

 

[vyv_cox]

Does the old antifouling contain any silicones? Inhibitor for many paint and resin systems.

 

[Pasarell]

How long since you applied it? Primocon uses the same solvent as many antifoulings so they are likely to be softened temporarily by putting Primocon over the top whereas the new grp would not. There are other possible reasons but I suggest this is about 90% probable

 

[Spirit (of Glenans)]

If it were me I would have just primed the repaired bits and then put on a coat or two of a/f. Perhaps you can remove the primer with thinners and start again?

 

[Quandary]

The OP did exacly what International paints recommend, Primocon is marketed as a bridging primer with the implication that you do not need it if you are applying antifouling over older stuff known to be the same. With the proviso referred to above regarding someone not having been daft enough to use a silicone coating on a sailing yacht I would be confident that the coating will harden up some, the solvents should have been the same. Eroding antifoulings do tend to be quite soft anyway.
Having said that, if it wus me. I would have used Jotun Vinyguard 88, though that is because I believe it is a bit more versatile and the price is not quite so silly, we have a responsibility to resist International Paints effort to milk us by dominating the market.

 

[webcraft]

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Seems to harden afterwards. The secret is to slap it on very, very quickly - if you then overbrush the a/f underneath is softened.

I'll sand down the couple of really gnarly bits.

- W

 

[johnalison]

I had some adhesion problems in patches with my old AF. My routine was to paint with Primocon, overlapping the edges. I then sanded the edges to feather them smooth and then repainted the patches with Primocon before the main antifouling.