Paint System 1 or 2 Part Epoxy

[akswimdog]

Greetings,

I'm looking for paint system advice/information for an old hull which has recently undergone an extensive refit thereby sporting a newly laid fiberglass deck, cockpit with all new sheer clamp, deck beams, carlines, etc...

I will be eventually be putting a non-skid coating/sand on the deck. Now its time to prime so want to know whether to go with a 1 part epoxy or 2 part epoxy primer and subsequent system...

One piece of advice I was given was to stay away from the two-part because it is too brittle and prone to cracking while the one-part is more ductile and will be more forgiving.

If someone has experience in this I'd be forever grateful if you would choose to share your expertise. Many thanks in advance...

[boatpoker]

There are pro's and cons to both, I'll let others deal with that. The one piece of advice I will offer is that no matter your choice, go with two part primer it is 100 times better than one part primer for both systems.

[akswimdog]

I appreciate that-

I guess that was one of my questions as well.... whether or not I have to stay with a one-part or two-part system once I make that decision for the primer.... ?? But it sounds like they may be interchangeable in terms of what topcoat I choose... Is your preference for the two-part based on wear and tare, ease of application....both...????

I admit to being flummoxed on everything paint so I apologize for all the Q&A- Just trying to give myself some basis to make a decision from. Thanks very much!!

[boatpoker]

My recommendation to use the two part primer is based on it's adhesive qualities to the substrate and to the top coat being far superior to the one part primer.

[akswimdog]

Got it! Thanks BP for specifying about the substrate! That's what I'm looking for- Much appreciated!! Best-

[barnakiel]

I would start at the other end and look at the finish first, then I would use the primer recommended by the maker of the finish.

I hate using 2-part primers (time, mess, cost) and I avoid 2-part finishes (hard to see any difference when applied by a non-pro). But in some jobs (e.g. bottom barrier coat) or in some finish standards (e.g. gloss topsides) many professionals will go for 2-part products.

Outcome: if you want a top shelf outcome and you have the time, skill and budget, you may opt for the 2-part way.

b.

[sww914]

I was really pleased with the Interlux Brightside 1 part epoxy that I applied on my cabin top. It covered really well and flowed out beautifully with the roll & tip method, even with a crappy brush. I've painted a few thousand cars so my expectations are high.
It's only been a year but it hasn't lost any gloss.

[akswimdog]

Thank you, I appreciate that perspective! Do you know if there is any merit to the comment that the two-part is more prone to cracking because its not as ductile as a one-part system? It does sound like the two-part system may be more durable...(+/). Thanks again!!

[akswimdog]

Originally Posted by sww914

I was really pleased with the Interlux Brightside 1 part epoxy that I applied on my cabin top. It covered really well and flowed out beautifully with the roll & tip method, even with a crappy brush. I've painted a few thousand cars so my expectations are high.
It's only been a year but it hasn't lost any gloss.

Thanks for that- When you painted your cabin were you painting over a previous coating or was it on new glass? If on a previous coating, do you remember what it was and was that a consideration as to why you went with the Inter Brightside...I guess what I'm wondering is did you spend time figuring out what would be compatible or were you just lucky? I'm just trying to get a grip on how precise I need to be.... Thank you!

[sww914]

After I sanded down all the old cracked stuff and filled the voids and sanded again, I primed with Interlux 1 part primer. It was a poor quality product (it didn't dry well) and I'd have to follow the advice of the previous poster who recommended a catalyzed product.
In autobody we'd put nearly any brand of paint over whichever catalyzed primer was our favorite at that time and we never had any compatability issues as long as we used urethane, polyester, or epoxy primer (all catalyzed). Some epoxys and urethanes won't go over some lacquer primers but I don't think that lacquer primer is even available anymore, at least not on the W coast.
I didn't take a lot of time deciding, the paint guru at the chandelery recommended the interlux because I didn't want to spend a lot of money and ease of application was at the top of my list.
Compatability isn't your biggest worry. Proper technique is the hard part.
You don't have to primer everything. Talk to a great chandelery and they can steer you in the right direction.

[sww914]

Let me amend that. You're in Alaska. Your biggest worry is temperature.

[Reefmagnet]

Single pack paints are more flexible then two pack, and are generally best used on timber boats for this reason. I think fibreglass is rigid enough for this not to be an issue. Single packs are easier to touch up as well, but are softer and less abrasion resistant then two pack. They will also have a shorter service life when compared to two pack paint. You would usually use the same system you decide on i.e. single or two pack for primers, undercoats and topcoats.

[akswimdog]

Originally Posted by sww914

After I sanded down all the old cracked stuff and filled the voids and sanded again, I primed with Interlux 1 part primer. It was a poor quality product (it didn't dry well) and I'd have to follow the advice of the previous poster who recommended a catalyzed product.
In autobody we'd put nearly any brand of paint over whichever catalyzed primer was our favorite at that time and we never had any compatability issues as long as we used urethane, polyester, or epoxy primer (all catalyzed). Some epoxys and urethanes won't go over some lacquer primers but I don't think that lacquer primer is even available anymore, at least not on the W coast.
I didn't take a lot of time deciding, the paint guru at the chandelery recommended the interlux because I didn't want to spend a lot of money and ease of application was at the top of my list.
Compatability isn't your biggest worry. Proper technique is the hard part.
You don't have to primer everything. Talk to a great chandelery and they can steer you in the right direction.

Good Stuff Steve- Thanks for the detail! I've heard similar advice that the hardest part or rather the most important part of the job is the set-up...I know in welding we used to say, "Setup is everything!!" Obviously it applies to painting as well- I appreciate the info!!

[akswimdog]

Originally Posted by Reefmagnet

Single pack paints are more flexible then two pack, and are generally best used on timber boats for this reason. I think fibreglass is rigid enough for this not to be an issue. Single packs are easier to touch up as well, but are softer and less abrasion resistant then two pack. They will also have a shorter service life when compared to two pack paint. You would usually use the same system you decide on i.e. single or two pack for primers, undercoats and topcoats.

Thanks Reef- Now you're getting to the crux of my question and what was particularly confusing to me...My hull is one of the strongest fiberglass hulls fabbed in its day (ingrid 38) but the new construction (sheer clamp, deck, doghouse is wood with a fiberglass overlay on the deck....so while there's wood involved, I don't think the hull will sag and hog like a wood hull but I'm still conflicted with the wood members for the structural deck components....(If what I just said makes better sense to you than me you're a better man-) SHOULD I be worried more about using the more ductile one-part given the wood components or look for something to better match the stiffness of the hull in the two-part....Geez....too many choices!!! Also I appreciate you comments about sticking with a 'system-type' all the way through. Great comments, thanks!

[akswimdog]

Originally Posted by sww914

Let me amend that. You're in Alaska. Your biggest worry is temperature.

So Steve, given the huge temp range here in Alaska......I should be looking at......???? Something more ductile???? yes/no....