Jotsun Industrial Marine Primer

[ianto7]

Hi, I just completed scraping and sanding 30 years of old antifoul and primers off my 22 foot GRP sailboat. Following an article in the PBO yachting magazine they suggest using a primer to seal the GRP, has anybody used Jotan Industrial Marine Expoxy GRP primer, prior to putting there antifoul
Many thanks

Ian

 

[Caer Urfa]

Hi Ian
Have you sanded back to the gel coat? I assume the hull?

I have used Jotun paints for years and have used their Vinyguard silvergrey primer before applying 2 x coats of antifoul https://www.smlmarinepaints.co.uk/primers and this usually last me two years IN seawater
Their 2 1/2 litre tin should easily do you boat with spare for a second coat.

Mix well before applying and allow to stand to release air bubbles with another quick stir between topping up your paint tray, I used a 3" (100 mm) roller no problem

However are you talking about a two pack epoxy for osmosis protection? which is completely different, years ago I used International Gelshield 200 but Jotun will have an equivalent, in this case whichever make you choose ONLY mix what you can apply in 20 minutes per tray otherwise it will start to go off or suggest you speak to them on the phone as they are very helpful

However remember you can apply a one coat primer onto a two coat epoxy, BUT you can not apply a two coat epoxy onto a one coat primer !

No connection just a satisfied customer for many years

Good luck Mike

 

[ianto7]

Thanks Mike for your reply, yes I have more or less sanded back to the Gel coat apart from some residual primer, didn't want to go too deep. The Gel coat looks good and I don't think I have any problems with osmosis, I just wanted to get a smooth surface base for the antifoul as it has been like the moon surface since I bought her 4 years ago. However after spending many hours taking it all back I wanted to make sure there was a good water seal primer before starting back with the antifoul. The Gelshield 200 seams rather expensive and probably unnecessary for my needs so I was just looking for a cheaper but good alternative, sounds as if this stuff will do the job, don't want to be scraping and sanding back any time soon

Many regards Ian

 

[Quandary]

I would second the Jotun Vinyguard recommendation though it is not epoxy it is much easier to use. It is not very different from Primocon but perhaps more versatile, I first used it as a transition coat between Jotuns Penguard epoxy and the antifouling but it is also a great metal primer and not too expensive, it keeps well. Jotun have a considerable range of two pack epoxy paints for different purposes, a lot of them developed for use on oil rigs including direct to rust two pack primers, they have a website to explain them and to designate the appropriate thinners, they also supply a low temperature additive which allows the stuff to be used in winter, even up here. Having made all the effort to clean right back to the gelcoat I would do a proper priming job, the cost is not that great compared to having to do it all again.
I usually buy from SML, if you live in Highland Scotland you select suppliers who do not screw you on carriage charges.