Do I Really Need an Epoxy Barrier Coat ?! Help Needed ASAP !

[windtraveler]

I know there are tons of threads on this but I'm having trouble deciphering between what "I NEED to do" and what would "be a good idea to do" and I'm planning on starting tomorrow!

Keep in mind that we are currently in Chicago but will be leaving this fall to sail "around" the world - at least to the caribbean, the south pacific, and beyond for about 2-3 years. We are limited on time as we have many projects to complete before leaving this fall. The boat seems to have been taken very good care of by the, at least, 3 PO's. It's most likely been in the Great Lakes for it's lifetime.

We already scraped at least a couple layers of paint - with chisels and carbide scrapers. Then we power sanded with 80 grit to get any remaining paint off and smooth it out. I don't really know what layer we are at now. Are we at an existing barrier coat or are we down to gelcoat?? I just don't know. The hull is showing NO signs of any blistering - it appears to be in great shape for a 35 year old boat - it's a Hallberg-Rassy 35 Rasmus. This leads me to the question...

Do I really NEED to put on 2-4 coats of InterProtect 2000 barrier coat before applying 2 coats of West Marine PCA Gold (rebranded Pettit Ultima SR 40) ablative antifouling paint. Or do I just need 1 coat of InterProtect 2000 or other product as a primer before the 2 coats of paint. Or, and this is obviously what I'm hoping you'll say is ok... can I just get away with 2 coats of bottom/antifouling paint?!

Please see our blog with pictures of the hull before and after stripping and sanding the previous antifouling paint. Windtraveler: I think I can, I think I can, I think I can.....

Thanks for your help!

Scott (& Brittany)

[SeaBungalow]

After we removed our bottom paint and gelcoat and did a multitude of blister repairs, and let it dry out for 10+ months we ended up putting 6 coats of Interprotect. The yard thought we were crazy. They suggested 2 was plenty.

Pictures can be found on our blog. Was not a fun job!

[CharlieCobra]

If you'd like to avoid a very expensive blister repair job later, then yes, you need it.

[witzgall]

Do you have blisters now? If not, then no way do you need the epoxy. Blistering happens more easily in fresh vs. salt water, so your boat is already in the worst situation for this to happen.

Chris

[S/V_Surya]

I have done the bottom peal on my 32 1976 columbia back in late eighties. Five years later they were back. Now I have a 1974 gulfstar that needed major work on keel. Blisters were not a big problem but there were some. I just fixed individual ones and that is all I am going to do. I did remove most of the old bottom paint down to gel coat. So my advice is if it ain broke don't fix it.

[CharlieCobra]

Ok, first of all. Just because he may not have them yet doesn't mean he won't later. Polyester resin is NOT waterproof. Epoxy resin and barrier coat is much more resistant to water intrusion. There are very few substances and coatings available that ARE 100% waterproof. Water always wins eventually but the barrier coat greatly extends the life of the GRP lamination. The ability of his HR to avoid blistering also depends on when it was built and with which resin. Some builds just aren't prone to blistering or osmosis.

[windtraveler]

See, this is typical of all the forums I've read! One person will say you're stupid not to barrier coat and others will say you don't need it.

Witzgall - no, there are no blisters or signs of repaired blisters - and it's most likely been in fresh water it's whole 35 year life.

I'm just worried that when we scraped and sanded that we may have taken off a barrier coat which is why I'm leaning towards meeting in the middle and just putting 2 coats of barrier on (rather than 4 coats) and 2 coats paint and calling the job done!

We could do under all the pads with 2 coats barrier and 2 coats paint on Saturday. And do the rest of hull with the same on Sunday.

[David_Old_Jersey]

Originally Posted by windtraveler

We already scraped at least a couple layers of paint - with chisels and carbide scrapers.

Sounds fun I would've got someone in to "blast" it with grit..........

I don't really know what layer we are at now. Are we at an existing barrier coat or are we down to gelcoat?? I just don't know.

That comment surprises me - especially given the time you have recently spent underneath her but, whatever, if it ain't paint I would stop scraping

The hull is showing NO signs of any blistering - it appears to be in great shape for a 35 year old boat - it's a Hallberg-Rassy 35 Rasmus.

Nice boat

No signs of blistering after 35 years would be enough for me to decide to go with a simple primer coat and then a couple of coats of straight antifoul.......whatever brands go together (too lazy to google your suggestions - but I wouldn't go for any special (aka $$$ ) formulations / barrier coats / voodoo preperations ). If it worked for the last 35 then odds are good for another 35.

If I am proved wrong in the year 2045 I will give your money back (for this advice )

[Adelie]

Water temp also has a BIG effect on blistering, most chemical processes procede faster at higher temps, including osmosis and the water/resin reactions that generate the acids(?) producing the blisters.

If the boat has spent 35ish years in the Great Lakes which are fairly cold year round, it doesn't surprise that he hasn't got blisters. I'm not saying he's going get blisters as soon as he hits the tropics, but past performance in cold water is no indicator for future performance in warm waters.

[witzgall]

If a 35 year+ boat does not have blisters, then I would not put the $$$ into labor intensive, costly work that MOST LIKEly, will not be needed. Yes, I could be wrong, but hey, if you want to hedge your bets, but that $$$ instead into an interest bearing acct, and if you need to do the work later, you will have more $$$ to do so.

Another thing that most miss. Barrier coats keep water from moving across it from both directions. So if you have some moisture in the hull, gelcoat, what ever, it will not come out and may blister the barrier coat itself trying to get out. Chew on that one!


Chris

[Pete7]

Scott, presumably the boat is out of the water, you have scraped it to within an inch of its life and its now dry. All you have to do it paint a couple of extra coats on the hull.

Alternatively if you don't in a few years time you could be back to lifting her out, scraping it back again and then painting on the epoxy resin, and a whole load of pain again to do it.

I would have someone measure the hull for moisture who knows what they are doing, probably a professional surveyor. If its dry, then go for the epoxy now. If its wet, then epoxy won't work and you would have to stay out for months to dry out, so not worth it.

We have an epoxy coating, applied by the previous owner at the 10 year point because they decided to keep the boat long term. When we bought her at the 19 year point our surveyor measured the moisture within an hour of lifting out and scraping 30 patches, then declared the readings very low and similar to the topsides used as reference. The epoxy coating was a plus when we were deciding if to buy or not.

HR have a great reputation in Europe for quality and prices to match, anything you do to maintain this yacht must be worth that extra little bit of effort to maintain her. So out with the brushes and by Sunday afternoon the job will be done

Pete

[SkiprJohn]

I vote for "you don't need an epoxy barrier coat." You will be doing a haulout every 3 years or more often so check your hull for blisters at each haulout and when they appear repair them. You can't repair them before they are there. Just my opinion.
kind regards,

[leslie]

If you have the money and the time and wish to keep the boat for the nex ten years...yes do it but if you wish to cruise as quickly and cheaply as possible dont. If it has no blisters yet chances are it wont in 5 years time. By then you would sell it. Slight osmosis does not affect the sale value of a vessel of that age. Many new boats have osmosis after 2 or 3 years. The fact that she came from the great lakes might suggest that she was on the hard over winter. This will give the hull time to dry out resuling in an olb boat with no osmosis. Osmosis also arely affects the structural soundness of a vessel as long as blisters are not much larger than 3" in diameter. Only about 1 in 1000 hull will be condemed due to osmosis. Epoxy hull coating is great for prevention but hey if it is not broken why fix it? Its not like you take a spare mast with you when you go sailing.

[amarinesurveyor]

I say since there are no blisters in 35 years, you are probably better off not applying any barrier coat. Blisters occur most times from problems with the lay-up; uncatalized(sp?) resin or air voids and dry lay-up.
I have also seen boats with barrier coat applied develop blisters under the barrier coat due to trapped moisture. If you do decide to barrier you are going to be looking at a long dry-out process.
Brian

[windtraveler]

Although the answers are all over the board, thank you for very much to everyone that has responded.

Alright, so let's say we decided NOT to do the InterProtect as a barrier coat. Should we still apply 1 coat as a primer coat? Or should we use a different primer?

BTW - It's been out of the water since October - and it's been inside for about a month and a half so the hull should be dry enough.

Scott