Clear Penetrating Epoxy Sealer as a "primer" for teak?

[Stumble]

Originally Posted by nhschneider

I have used Smith's Clear Penetrating Epoxy Sealer for about 20 years and have been so pleased with the results that I'm getting desperate now that my personal inventory is getting low and the product isn't available in the Caribbean. All the bare wood I'm preparing to finish gets coated with CPES. I have found that the finish adheres better and lasts longer if I've used CPES first. I have researched thinning an epoxy resin like the West System but the company doesn't recommend it. As far as the differential in costs are concerned, at defender.com, a 2-pint package of Smith's is about US$47 whereas one quart of West System 105 Resin is about US$44 but you'd still need to buy the West System hardener at about US$22 for 7 ounces. Granted, the West System would be diluted but the difference per application would probably be pennies.

Fair winds and calm seas.

Pull the MSDS for CPES. It's standard 100% solids epoxy with a bunch of thinners in it that are available off the shelf. Buy WEST or Systems 3 and dump the same amount of thinners that CPES uses and you will get a comparable product. If I remember right CPES is only about 40% epoxy and the rest a mixture of xylene, acetone, MEK, and other nonsense. You can make it for about 1/2 the price.

[Three Sisters]

I'd say the same. Try a homebrew on a test piece. That's how I got started using the thinned stuff. Went to the box store and bought a can of laquer thinner, xylene, alcohol, acetone and tried each one. The laquer thinner provided the best results with the 1:1 epoxy...and no fire. I mean, the application is meant for a tuned-up wood sealer, not for laminating cloth or structural pieces. Our next experiment will be a topcoat of automotive clearcoat. A major determining factor on cure has been humidity. Never have tried West Mas or Awl anything.

Best of luck in whatever path you choose. Completely Re-doing brightwork every 6 months has to be quite the task

[Celestialsailor]

Originally Posted by TeddyDiver

Nope! CPES is a hoax.. and teak being oily wood needs oil wiped of with acetone if using any epoxy based coat.

BR Teddy

...and you know this how?

I've been using CPES for years with great success.

[TeddyDiver]

Originally Posted by Celestialsailor

...and you know this how?

I've been using CPES for years with great success.

Sure, the right way to do teak is to wipe with acetone, let it evaporate and seal with proper epoxy. The right way to treat a rotten board in a boat is to chance it with a new one. The right way to treat rotten board in a 100yrs old my grandgrandfarther build it hut is to treat the board with glycol (monoethyleneglycol), a bit more glycol and let it be until the surface is dry and treat with good epoxy.
I know this becouse I've done all the above

The bad way do to all this is to mix together good epoxy, acetone, glycol and some cheaper ingredients and say it's good..

Does that make sense

BR Teddy

[minaret]

You will get a much better bond epoxy to teak if you wipe with MEK instead of tone and then thin your sealer coat of epoxy with MEK as well.

It's quite obvious the first time you do this. Wipe freshly sanded teak with a wet acetone rag, and not much comes off, just a hint of light brown on the rag. Do the same with an MEK rag, and you will instantly see that a whole lot more brown stuff comes off on the rag. This is teak oil. I keep wiping with very wet rags till they come back clean. Allow a minimum of half hour for solvent to evaporate, and then apply the first sealer coat quick before oil rises to the surface again. Wait overnight, and you will find if you rewipe you don't come back with a clean rag anymore.


Teak oil really just isn't very soluble in acetone, which is true of many oily products. But MEK eats it right up!



Preheating the substrate and coating as it cools also makes a huge difference. This can be as simple as picking the right time of day to seal.

[Beausoleil]

Wow - I post a query before heading out for the weekend, and all hell breaks loose.

Seems to be a significant love-hate relationship with CPES. I can understand the logic behind it not restoring rotted wood to its natural strength, but I'm doing brightwork, not restoring rotted wood. As far as the "lack" of moisture and UV resistance - well, I thought that was what the UV topcoat is supposed to accomplish. Whether it's 2-part Bristol Finish or one-part polyurethane with UV additives, or a good spar varnish, it's the top coats not the primer that give moisture resistance, right?

I guess what's really frustrating is that multiple posters mention qualities which are directly in opposition to each other - it's too hard and brittle, it's soft like "a skateboard wheel". I read some of the old threads, and it seems to be two camps - it's junk, and it's great. Sorry to open the proverbial can of worms...

[TeddyDiver]

Originally Posted by Beausoleil

Wow - I post a query before heading out for the weekend, and all hell breaks loose..

fun

[Celestialsailor]

Originally Posted by Celestialsailor

...and you know this how?

I've been using CPES for years with great success.

Originally Posted by TeddyDiver

Sure, the right way to do teak is to wipe with acetone, let it evaporate and seal with proper epoxy. The right way to treat a rotten board in a boat is to chance it with a new one. The right way to treat rotten board in a 100yrs old my grandgrandfarther build it hut is to treat the board with glycol (monoethyleneglycol), a bit more glycol and let it be until the surface is dry and treat with good epoxy.
I know this becouse I've done all the above

The bad way do to all this is to mix together good epoxy, acetone, glycol and some cheaper ingredients and say it's good..

Does that make sense

BR Teddy

So when I asked "you know this how? The answer is you've done it your way and it works. Just like the other people have done it with CPES and it worked.

Originally Posted by Beausoleil

Wow - I post a query before heading out for the weekend, and all hell breaks loose.

Ya...that kinda happens here.

[Three Sisters]

Originally Posted by Beausoleil

Wow - I post a query before heading out for the weekend, and all hell breaks loose.

Seems to be a significant love-hate relationship with CPES. I can understand the logic behind it not restoring rotted wood to its natural strength, but I'm doing brightwork, not restoring rotted wood. As far as the "lack" of moisture and UV resistance - well, I thought that was what the UV topcoat is supposed to accomplish. Whether it's 2-part Bristol Finish or one-part polyurethane with UV additives, or a good spar varnish, it's the top coats not the primer that give moisture resistance, right?

I guess what's really frustrating is that multiple posters mention qualities which are directly in opposition to each other - it's too hard and brittle, it's soft like "a skateboard wheel". I read some of the old threads, and it seems to be two camps - it's junk, and it's great. Sorry to open the proverbial can of worms...

Oh your the thread starter.

The CPES, or if you use regular epoxy or homebrew thinned epoxy; there's alot of brightwork from looking at your blog. I'm thinking the above mentioned mixtures would be used on bare wood.

Are you considering CPES over already finished brightwork ?

I couldn't say if that would be it's intended purpose.

Off topic, the photo of the gal holding up the boulder at The Baths, that was sweet, thanks !

[leftbrainstuff]

Originally Posted by bletso

And your source for this information is? Contrary to your belief, I have had very good results with CPES and their Teak glue/epoxy. I have been using it for four years now.

+1

Smiths Penetrating epoxy is a great sealer before coating. Have used west system and varnish over CPES on high wear areas.


Sent from my SM-N900T using Cruisers Sailing Forum mobile app

[TeddyDiver]

Originally Posted by minaret

You will get a much better bond epoxy to teak if you wipe with MEK instead of tone and then thin your sealer coat of epoxy with MEK as well.

I don't have MEK available locally and ordinary carriers don't deliver hazardous chemicals.. but thanks for the tip

But nevertheless, if needed an additive with epoxy blend it as Minaret, don't use premium priced one with all kind of stuff.

BR Teddy

[Beausoleil]

Originally Posted by Three Sisters

Are you considering CPES over already finished brightwork ?

I couldn't say if that would be it's intended purpose.

Nope - I specifically said I was intending to use CPES as a base coat, as in a sealer over bare wood. Right now, virtually all the finish is gone.

My thinking was than CPES penetrates the wood better than thinned polyurethane (which we did last time) or varnish. And to me (an EE rather than a ChemEng or chemist), I would think that Bristol Finish over not-quite cured CPES would have a better chemical bond than poly or varnish. And to my non-chemist mind, CPES would provide a better mechanical bond to teak than a normal viscosity epoxy.

We've done Bristol Finish on bare teak on parts of our brightwork before, and found that it lasted at least a couple years in the tropical sun before beginning to fail. I was just wondering if we could do better...

[Three Sisters]

I'd want to obtain the consensus at the Bristol Finish technical division before continuing.

The chemical make-up of the two products may conflict considering the list making up the CPES.

[Beausoleil]

Originally Posted by Three Sisters

I'd want to obtain the consensus at the Bristol Finish technical division before continuing.

The chemical make-up of the two products may conflict considering the list making up the CPES.

Found the following at the Bristol Finish website:

"One way to greatly reduce the chance of moisture intrusion is to seal up a wood project completely with a thin coat of epoxy or penetrating epoxy sealer (PES). If a piece is going to be re-mounted make sure to epoxy over the bungs after mounting. For the prep treat the epoxy the same way as any other existing coating."

I submitted a question to them regarding specific use of CPES. I'll post the response when I get it...

[TeddyDiver]

Originally Posted by Beausoleil

Found the following at the Bristol Finish website:

"One way to greatly reduce the chance of moisture intrusion is to seal up a wood project completely with a thin coat of epoxy or penetrating epoxy sealer (PES). If a piece is going to be re-mounted make sure to epoxy over the bungs after mounting. For the prep treat the epoxy the same way as any other existing coating."

I submitted a question to them regarding specific use of CPES. I'll post the response when I get it...

In the quote they were not speaking of Teak which is quite different from most wood..