Sealing plywood after fairing - Interprotect 2000e?

[chowdan]

Hey all,

I am currently finishing up my head rebuild and one of the things my wife and I decided was that since this is a wet head, we do not want to deal with rot ever again in this area. All of the new cabinetry we have built is completely epoxy coated, and fastened with epoxy - no penetrations into the wood so we should "never" see the new material decay(unless the epoxy coating fails).

I am in the process of fairing smooth the bulkheads with epoxy fairing compound, and one thing I'm thinking to "protect" them is to do an epoxy barrier coat with something like Interlux Interprotect 2000e.

I was thinking about doing just epoxy, but if theres any flexing in the bulkhead(of any sort) i suspect we'd see the epoxy fail in some areas and allow moisture in. Has anyone used 2000e on a plywood bulkhead?

Opinions on this method, or should I just sheath the bulkheads with a thin layer of glass(like a 4oz cloth) before painting the surface?

[Cheechako]

Well, you should be good to go for quite a time. I would just paint what you have sealed. If there is a hatch or skylite, epoxy doesn't do well in UV sunlight, so paint is good to have over it.
Isn't 2000e bottom barrier epoxy? Why would you use that? As I remember it's a little gummy, not a lot but....

[Lepke]

When I do a shower, I use 2.0 rsm and epoxy on the floor and at least 6" up the sides. I use 2.0 because it holds more epoxy and I never had a cracking problem. Whenever I use plywood, I seal it with a reduced epoxy so it absorbs, then regular epoxy over that.

[chowdan]

Originally Posted by Cheechako

Well, you should be good to go for quite a time. I would just paint what you have sealed. If there is a hatch or skylite, epoxy doesn't do well in UV sunlight, so paint is good to have over it.
Isn't 2000e bottom barrier epoxy? Why would you use that? As I remember it's a little gummy, not a lot but....

I couldnt recall what 2000e was like when i did my bottom, it's been too long and too many other projects that has gone on since then. I was reading their details and they said it's okay to use on plywood, but sometimes i dont trust manufacturers. Rather have real world experience. Whatever we end up with, we are probably going to be painting with an outdoor alkyd enamel paint, so no epoxy will be exposed. My thought on using the barrier coat would be to guarantee a water tight barrier on the walls of the shower(no section of the plywood in theory would see water then).

Originally Posted by Lepke

When I do a shower, I use 2.0 rsm and epoxy on the floor and at least 6" up the sides. I use 2.0 because it holds more epoxy and I never had a cracking problem. Whenever I use plywood, I seal it with a reduced epoxy so it absorbs, then regular epoxy over that.

What is rsm? I could run the glass layer up higher than the 4" it's currently at without too much trouble, but also just doing a sheath of 4oz wouldn't been too hard either

[s/v Jedi]

Interprotect 2000 cures rock hard, no gumming at all. In fact, it cures so hard that it’s tough to get paint to stick to it, which is why it’s normally hot-coated for a chemical bond.

Yes, use Interprotect 2000. I’m about to test TotalProtect as well. Then I also tested another product: Totalboat Penetrating Epoxy. For treating plywood, we thin it 50% (!) with denatured alcohol and brush it on. This works really well and when you let cure some leftover in a little pot, you find that it cures flexible!
You can sand it afterwards, back to the wood fiber. It then looks like wood but feels like plastic. I have tested Epifanes varnish over it and that worked very well.

Still, for bulkheads I would use Interprotect.

[chowdan]

Originally Posted by s/v Jedi

Interprotect 2000 cures rock hard, no gumming at all. In fact, it cures so hard that it’s tough to get paint to stick to it, which is why it’s normally hot-coated for a chemical bond.

Yes, use Interprotect 2000. I’m about to test TotalProtect as well. Then I also tested another product: Totalboat Penetrating Epoxy. For treating plywood, we thin it 50% (!) with denatured alcohol and brush it on. This works really well and when you let cure some leftover in a little pot, you find that it cures flexible!
You can sand it afterwards, back to the wood fiber. It then looks like wood but feels like plastic. I have tested Epifanes varnish over it and that worked very well.

Still, for bulkheads I would use Interprotect.

I was under the impression it cured rock hard, but again, it's been so long since i played with it i couldn't remember. I was actually looking at Totalboats TotalProtect. I've never used their products due to cost being a tad higher than mixing up my own batches(typically with West as I have a good pricing source). Looking at TotalProtect pricing vs InterProtect, i'm seeing roughly a $2 price difference(totalprotect being cheaper with my source).

I'm curious how deep does the penetrating epoxy get into the wood, and more importantly, how deep does it need to be to actually seal it?

[garyfdl]

Contact Paul Oman at epoxy products.

https://www.epoxyproducts.com/

Put the question to him.

[Thumbs Up]

Pricey overkill. Find a Sherwyn Williams industrial outlet. By a 1:1 ratio epoxy paint/primer. (I forget the exact name). Has a little more UV protection and is a creamy white color. 1:1 is easier to proportion and the unused portion will have a good shelf life unlike 4:1 interprotect. The problem with epoxy primers is getting it to lay down smooth with a brush or roller. Look for a 3/16" or 1/8" nap phenolic core rollers. You will be better off spraying. Don't bother with the penetrating stuff. If you want easy sanding, go with Awlgrip 545 (also 1:1).

[garyfdl]

Originally Posted by garyfdl

Contact Paul Oman at epoxy products.

https://www.epoxyproducts.com/

Put the question to him.

Oh, and don't let the website fool you. While it is not 'professional' Paul is.

[Cheechako]

Originally Posted by s/v Jedi

Interprotect 2000 cures rock hard, no gumming at all. In fact, it cures so hard that it’s tough to get paint to stick to it, which is why it’s normally hot-coated for a chemical bond.

Yes, use Interprotect 2000. I’m about to test TotalProtect as well. Then I also tested another product: Totalboat Penetrating Epoxy. For treating plywood, we thin it 50% (!) with denatured alcohol and brush it on. This works really well and when you let cure some leftover in a little pot, you find that it cures flexible!
You can sand it afterwards, back to the wood fiber. It then looks like wood but feels like plastic. I have tested Epifanes varnish over it and that worked very well.

Still, for bulkheads I would use Interprotect.

hard or soft it's not how "hard it is" that has anything to do with getting things to stick, all epoxy requires a hot coat or a lot of sanding!
All I know is the boat in my avatar was 2000 undercoated and bottom painted by the yard, and when I had to repair a small area the 2000 was not brittle at all taking it off. Some parts came off the size of a couple of quarters in one piece. maybe it wan't mixed well enough or something, but one wonders... it is designed for a perfect world?

[s/v Jedi]

If a barrier coat comes off, the prep before putting it on was not done right. It’s just epoxy.

Penetrating epoxy from TotalBoat works great. It is a 2:1 ratio epoxy and I’ve gone through almost a gallon of resin and just bought a new kit. Not cheap.

So when you thin it 50% with denatured alcohol, it is easy to apply. I pour it on and use a 4” wide chip brush to spread and fully coat. I just did some plywood with red oak top veneer and in some spots you see it disappear so I hit it with a bit more immediately. After cure you will have some areas that are glossy and some flat. If it’s out of sight then it’s good to go but otherwise I first wash it with water and a Scotchbrite pad, then sand it all smooth back to what would be bare wood when it would be varnish. It will be rock hard and sealed, you don’t need a float coat. This is where I applied varnish over it and it looks and feels like varnished wood. For paint you can consider it a pn epoxy primer except there’s no pigment… which is why I recommend to use Interprotect instead.

I would not use Awlgrip 545 primer because that is way softer and really needs a topcoat.

The attached picture shows the underside of a new wall-mounted flip-up workbench I just built, after coating it with the penetrating epoxy.

[Allied39]

Plywood will check sooner or later even when sealed with epoxy unless fiberglass is used.

End grain plywood will check much sooner......not later.

I used two layers of 10 0z cloth and faired and painted over that. 20 years no issue.

I have recently been involved with a canadian built trawler that that was built glass on ply with west 16 years ago and is having multiple failures. It appears they used a single layer. I have not ascertained their base , IE staggered scarfed joints as I did or simply butt joints.....I suspect the latter.

My first sentence is what you should take note of if you do not wish to experience failure . Just my opinion based on experience.

[chowdan]

Turns out Sherwin Williams stuff runs about $150/kit(gallon/quart). So far interprotect is cheapest for me followed by total protect.

I'm thinking I'll do high solids interprotect if they have it in stock next week to give a thick coating and more importantly fill the wood grain smooth in areas I didn't need to fair.

Still up in the air about a sheath layer of glass. I guess I could always do that in a few years if I notice issues.

[s/v Jedi]

Originally Posted by chowdan

Turns out Sherwin Williams stuff runs about $150/kit(gallon/quart). So far interprotect is cheapest for me followed by total protect.

I'm thinking I'll do high solids interprotect if they have it in stock next week to give a thick coating and more importantly fill the wood grain smooth in areas I didn't need to fair.

Still up in the air about a sheath layer of glass. I guess I could always do that in a few years if I notice issues.

Sherwin Williams has TileClad which is often used. It is a two part epoxy that can be mixed in any color, gloss or eggshell. It comes in a 1:1 ratio in 1 gallon cans which makes minimum quantity 2 gallons mixed.
People speak highly of it but I have no direct experience with it.

[zstine]

Personally, I think Interlux 2000 is too thick and hard to go directly on wood. I'd use a thin epoxy that will soak into the wood and hot-coat it with a thickened mix after