Paint or Gelcoat?

[Bigjim]

I'm going to need to redo the entire deck of my 1978 Columbia 10.7. Should I use paint or gelcoat? Any opinions?

[Bigjim]

I just found that there is an existing thread for this topic here:

http://www.cruisersforum.com/forums/...nt-226718.html

Anyone have anything to add or refute?

[slug]

Use paint ...2 component system

[s/v Jedi]

Well yes, I would argue that a good paint system is a much better option, especially for horizontal surfaces that get the full UV dosis.

Ideally it starts with Awlgrip 545 epoxy primer. That stuff truly is awesome, greatly stabilizes the substrate and I would argue even reinforce it. The topcoat is to protect it from UV and for aesthetics. I would recommend the regular Awlgrip topcoat.

Does your deck have the wafer molded anti skid or something like sand in the gelcoat? If molded, keep the primer thin so as not to fill it. Use brush formula for catalyst and reducer.
If you have something like sand in the paint then I recommend the product “soft sand”, mix it through top coat paint and use a big brush to dab it to get the pattern.

[slug]

Originally Posted by s/v Jedi

Well yes, I would argue that a good paint system is a much better option, especially for horizontal surfaces that get the full UV dosis.

Ideally it starts with Awlgrip 545 epoxy primer. That stuff truly is awesome, greatly stabilizes the substrate and I would argue even reinforce it. The topcoat is to protect it from UV and for aesthetics. I would recommend the regular Awlgrip topcoat.

Does your deck have the wafer molded anti skid or something like sand in the gelcoat? If molded, keep the primer thin so as not to fill it. Use brush formula for catalyst and reducer.
If you have something like sand in the paint then I recommend the product “soft sand”, mix it through top coat paint and use a big brush to dab it to get the pattern.

I prefer to first use a substrate primer...like awlgrip hull guard, then 545

Molded non skid is always a pain to paint ...in some cases it's better to fill it in completely .

[s/v Jedi]

Originally Posted by slug

I prefer to first use a substrate primer...like awlgrip hull guard, then 545

Molded non skid is always a pain to paint ...in some cases it's better to fill it in completely .

I never used hull guard yet. I looked it up but can’t really find how it compares to 545. Do you know the advantages?

[slug]

It’s a very hard , waterproof , high adhesion primer

545 is a soft , sandable waterproof primer the promotes topcoat adhesion

For Technical painting ... metal...underwater ... always use a substrate primer

In many cases an all purpose , sand-able primer like 545 is all you need

Since I charge for work I tend to follow paint application schedule exactly

[mvweebles]

I asked this exact question of Steve D'Antonio a few months ago. He kindly allowed me to cut/paste his reply on Trawler Forum so I'm sure he'd be fine with my pasting it here. For him, it's not a close call - go with a decent two part paint such as Awl Grip of AlexSeal


While I continue to encounter this, gelcoat vs. paint, question from time to time, it continues to surprise me. In short, other than for repairs, gelcoat is best suited for use in a mold, i.e. it is applied to the inside of a female mold first, then fiberglass fabric and resin are applied on top of it, before the gelcoat is fully cured, thereby creating a very tenacious, chemical bond between the two.

Applying gelcoat, in paint-like fashion, for deck, cabin or whole hull applications, after the fact, has two results. One, it does not achieve a chemical bond with the underlying substrate. Two, when gelcoat cures while exposed to air, it becomes porous. I find that those who are willing to spray entire hulls in gelcoat do so because they understand the product, its strengths and weaknesses, and it can be sanded and buffed to near-perfection. Still, those reasons are not good enough in my opinion to choose it over poly-urethane, PU paint is the preferred approach by far.

It’s worth noting, typically, PU paint also does not achieve a chemical bond with its substrate, however, its ability to adhere tenaciously to properly profiled surfaces is considerable, and in my estimation it does so more effectively than gelcoat.

When it comes to two part paint, there are a number of choices, in both chemistry and manufacturer. This column covers some of the details, choices and trade-offs.

[s/v Jedi]

Originally Posted by slug

It’s a very hard , waterproof , high adhesion primer

545 is a soft , sandable waterproof primer the promotes topcoat adhesion

For Technical painting ... metal...underwater ... always use a substrate primer

In many cases an all purpose , sand-able primer like 545 is all you need

Since I charge for work I tend to follow paint application schedule exactly

Okay... that sounds a bit like Interprotect2000 ... is that comparable?

[valhalla360]

Originally Posted by slug

Use paint ...2 component system

We liked the 1 part we did because it was easier to touch up when you drop an anchor or bump a dock a little hard.

Either is better than gelcoat.

[Chotu]

Originally Posted by valhalla360

We liked the 1 part we did because it was easier to touch up when you drop an anchor or bump a dock a little hard.

Either is better than gelcoat.

Which 1 part did you use and how durable was it?
I have 2 part that looks the same as new 5 years later. Except where damaged. Trying to proceed with a plan for the topsides. Considering paint options. Don't want to respray the whole thing.

[valhalla360]

Originally Posted by Chotu

Which 1 part did you use and how durable was it?
I have 2 part that looks the same as new 5 years later. Except where damaged. Trying to proceed with a plan for the topsides. Considering paint options. Don't want to respray the whole thing.

We used Interlux Brightside and when we sold 4yr later, it was still nice and shiny never having buffed or waxed.

It was only where something hard hit it that the paint chipped but we kept a quart and 5 min to shake the can to mix it up and then a disposable foam brush and unless you get within inches, you wouldn't notice the touchup.

[slug]

Originally Posted by s/v Jedi

Okay... that sounds a bit like Interprotect2000 ... is that comparable?

I think so

In Europe international industrial paints are marketed with different names.

One of the nice features of awlgrip is that the marketing names always seem to be the same

[slug]

Originally Posted by valhalla360

We liked the 1 part we did because it was easier to touch up when you drop an anchor or bump a dock a little hard.

Either is better than gelcoat.

Single component will work

It’s just not at hard and not as Uv resistant

One benefit with 2 component is its ability to be applied wet on wet. No sanding

[valhalla360]

Originally Posted by slug

Single component will work

It’s just not at hard and not as Uv resistant

One benefit with 2 component is its ability to be applied wet on wet. No sanding

Yeah, you have to let it dry between coats. If you try to do thick layers, it doesn't work so well.

Durability...while we didn't keep the boat for 10yr, what we did see wasn't an issue.