CPES- (clear penetrating epoxy sealant)- uses, and how to make your own…

With all the talk, recomendations, plus my own personal use of LOTS of CPES products (ie. all the money I have spent on it)
I thought it migh be interesting to start a thread about this type of product.

Personally I have used the international everdure on my new ply and timber, and treated my old ply and timber with epiglass wood preserving epoxy, that contains a wood preserving toxin I think.

My main queery is- How can we make this stuff ourselves?
Though I have been told that while thinning epoxy is possible, the end result is not the same, and is less than ideal.
But I have a sneaking suspicion that this is simply a load of bollocks, designed to keep us all addicted to the product. Like selling us cordial already watered down, by telling us the water that comes out of our taps is just not good enough.
After all, CPES is a thicker epoxy that has been thinned with something (isn't it?),
question is, what with.

Now I did a little test or two. After letting a mixed portion of evidure (CPES) cure in a bucket, it turned out to be a stretchy flexy sort of hard jelly rubber like substance that would tear with shattering/fractures and sort of snap if folded to extreme.

I also tried thinning some west sytem epoxy with paint thinners and with acetone. I thinned it to the consistency of CPES, and I tried it on some ply. It seemed to seep in and behave very simarly. When it set, it also had the same sort of attributes as the set CPES did.

Now my tests have been far from thorough, just playing around with leftovers, but what does everyone else think, or what have people tried.
Success failures etc..

Can we make this stuff ourselves, and save ouselves a lot of money?
Or are we to believe the Hype?
Is there a real reason why CPES is something fundamentally different from a normal thicker epoxy resin that has been thinned?

Hans.

 

Hans,

Shouldn't be that hard to make penetrating epoxy at home. Just take a perfectly good resin and ruin it with the same solvents the commercial CPES products use.

Yoke.

 

Well that is what I was thinking (but without the ruining part),
While I did make some epoxy resin that penetrated, simply by thinning it, the shop people I have talked to say that this sort of thing is Far from the quality of CPES. Now I don't believe them, so I want to hear other peoples knowledge and expertise on the subject.
I am genuinly interested in your sceptiscism.
Do you think CPES is that bad/worthless?

On a lot of stuff that I have used it, like old timber that is has been stripped and cleaned for varnishing, I will saturate it with CPES, then apply a coat of "perfectly good resin" on top of this when the CPES is still tacky. Then prepared for marine varnish- the epoxy protecting the varnish underneath from water, and the varnish protecting the epoxy from UV. A perfect relationship I hope. This is for the aim of getting the epoxy deeper into the wood, and thus getting a deeper better bond with the wood.
On my new deck, the CPES has saturated down through the first veneer to solidify and strengthen it against scratches and water intrusion. It has then been primed over.

Thanks Hans.

 

Thanks Hans, after reading your post I had to go play with some resin

I think its probably not the same, but for what we do, and the money it'll save, its fine. Acetone evaporates quick and thins good, thats what you want. I'm sure that some chemists would have something to say about it, but fine, maby we'll learn something!
My vote for CEPS; worthless.

 

Hans,
The ingredients of CPES are as follows, and according to its followers are
what makes it superior to DIY thinned epoxy.Also, Evadure has no fungicide anymore.
In order of quantity. (From the MSDS , no actual proportions))

Aromatic Naphtha
xylene (common paint store solvent)
toluene (common paint store solvent)
isopropyl alcohol (2-propanol) (common, cheap rubbing alcohol)
2-butanone
4-methyl 2-pentanone
2-heptanone
4-methyl 2-hexanone
2-pentanone
dipropylene glycol monomethylether
diisobutyl ketone
ethyl acetate
isobutyl acetate
ethyl 3-ethoxy propionate
propylene glycol monomethylether acetate
hexyl acetate
isobutyl isobutyrate
diacetone alcohol
cyclohexanone
The first four are apparently, the bulk of the product.
I have heard it is a great product under varnish. But you still have to do at least 6 coats of UV inhibited over. I may import some for my brightwork.

BTW. Cheers for the moral support on the project.
Post some pic's of yours.

Roly

 

Hey Roly,
thanks for that CPES info.
I imagine that the different mix of solvents might be desinged to penetrate deeper and a larger range of materials.
What all the other stuff is, I wouldn't have a clue.
I am sure that some have a purpose, and a lot just make the ingredient list look good. It is like this with a lot of stuff. Cosmetics especially.

Can anyone recognise what the purpose of all that non-solvent stuff is?

Anyway Roly, check out my old and continuing thread
http://boatdesign.net/forums/showthread.php?t=11026
there are a fare few photos of my boat on that, with some recent aditions tonight.

Hey Figgy, did you try your mix on some wood?
How'd it go?
I think that soon I will do a little test with some scrap ply, coat some in the DIY and some in the real stuff, then paint it and leave it hanging off my swing mooring.

 

Hans, I just threw some on som scrap ply I had from another project and I found good penetration into the wood. The only thing I worry about is the acetone being able to evaporate out, thats the key, and im not so confident about it. I'll try some more tonight, and I look foward to hearing about what happens to the scraps on your mooring.
-Fig

 

That is a concern about the acetone evaporating out,
but wouldn't this be just the same with xylene and toluene?
I mean they are all pretty similar stuff.
Are we sure that all the solvent from CPES evaporates out?
I had a sneaking suspicion that when my navy blue topside paint began to bubble back to wood on the sunny side, it may have been from CPES solvents, not water. It wouldn't have explained all the bubbles but certainly two big patches of them.

M

 

Nice topic.

I remembered a similar thought by a user "seven up", who made his own by thinning with laquer thinner. I love laquer thinner for clean up, and it is always gone before you are done with it. Might be superior to acetone for evaporating.

I think I'm gonna try this myself.

Mike

 

Figgy, That is a concern about the acetone evaporating out or not.
But isn't there just as much a concern with CPES?
I mean xylene and toluene, and a lot of those solvents are all pretty similar.


Maybe with the DIY we have to make sure that the mix is not too hot, not to much hardener, or just use a slow hardener, to give the solvents time to evap, befor the rubber/jelly setting begins.

Once I get my boat out of the marina, and onto its swing mooring, and I get all my tools and resins and paint etc back home, then I will play around a bit more.

 

weird double posting by me,
sorry,
lost the page and then re-wrote-

Hey bilgeboy,
sorry, you posted while I was writing (second time)
What is the chemical name of the solvent in Laquer Thinner?

Plus, to anyone-
can we recognise any of those ingredients in the list Roly provided?

 

Good question.

I've studied organic chemistry for a year, and I still don't have a clue whats in lacquer thinner. Googling it just now, I realized I can't even spell it correctly. I think its really laCquer thinner.

First page identified these chemicals: http://hillbrothers.com/msds/pdf/n/lacquer-thinner-mckb.pdf

Aliphatic petroleum distillates
Isobutyl Acetate
Toluene
Isopropanolol
Methyl Ethyl Ketone
Methyl Alcohol
Normal Butanol

Here is another one http://www.setonresourcecenter.com/msds/docs/wcd00034/wcd03410.htm

SECTION XII - Ingredients/Identity Information
Ingredient # 01
Ingredient Name ACETONE; DIMETHYL KETONE (10-20%)

Ingredient # 02
Ingredient Name TOLUENE (40-50%)

Ingredient # 03
Ingredient Name PROPYLENEGLYCOL MONOMETHYL ETHER ACETATE, 1-METHOXY-2-PROPANOL ACETATE (1-5%)

Ingredient # 04
Ingredient Name ISOPROPYL ALCOHOL (10-20%)

Ingredient # 05
Ingredient Name PETROLEUM DISTILLATES (10-20%)

Anyway, you can see that although there may be slight variability by manufacturer, they are very similar.

Looks like Toluene is the major component,
then petroleum distillates,
isopropyl alcohol (AKA isopropranolol),
dimethyl ketone or methyl ethyl ketone (manufacturer variability?)
acetates with very long prefixes not worth trying to type.

Compared to what Roly typed, its looking pretty good! I've got to get back to work...

Mike

 

Ever tried sanding a piece of wood that was coated with CPES a long time ago? That smell is the trapped solvents finally getting out.

To my admittedly simplistic way of thinking, once the epoxy is not flowing anymore, the escaping solvents must leave pores behind.

Yoke.

 

Thinned epoxy has been proven to be way more water pemeable than neat epoxy. Therefore, I would be only comfortable leaving it to flash off all the solvent and then 100% epoxy over top.(several days between) Gotta be mindful of a blush also.


The glycol's in CPES I suspect are the fungicides.
Epiglass, Courtnauds or whoever owns the company now, sayes that they
removed the preservative because of "problems." (Evadure)

 

In a previous life I worked with this stuff. If memory serves me right, the ketones, ie acetone and methyl ethyl ketone are more reactive with the epoxy resine than the toluene and xylene. The acetone is likely to degrade the quality of the epoxy bonds. However, the acetone will evaporate quicker. I would expect the acetone to evaporate quickly even from wood. The toluene evaporates a little bit quicker than xylene but is more expensive.
If you want to make your own, I suggest getting some emperical data with a two part solvent mixture, acetone and xylene. You want the min amount of acetone so as not to degrade the epoxy bonds, but still get quick evaporation. Xylen will thin the resine for penetration, but should slow evaporation. Find the optimum (minium) acetone and xylene which gives the penetration and reasonable evaporation times.

Ethylene glycol ( antifreeze) makes a good fungicide and kills bacteria. Ethylene glycol could be applied before anything else as a good penetrating fungicide.