Substitute for CPES

[mikeschn]

Does home depot, or other big box store have anything that would be an acceptable substitute for CPES?

I'd like to waterproof my sides on Wednesday, and an order to the rot doctor wouldn't arrive in time.

Any ideas?

Mike...

[SteveH]

Mike,

I don't think you will find anything like it at Home Depot, but if you have a West Marine around you, they sell epoxy resin by the gallon at a pretty good price. If you would mix some of that, and then thin it with alcohol, it should work the same. We do that with model airplanes all the time and it makes the wood impervious to the oil and stuff in the fuel.

[Geron]

I had the same thought as suggested by SteveH's post as I epoxied my TD. Why not thin the epoxy with denatured alcohol for greater penetration??? Gradually adding less and less DN alcohol as the layers build for a thicker brew for smoothing and filling.

Maybe some epoxy experts can fill us in.

g

[Miriam C.]

MIke some of the box stores carry Bondo marine epoxy. It isn't too bad and doesn't thicken fast if used in small amounts. You might be able to thin "Table epoxy" too but that might be a polly blend. Not sure.

GitRdun

[Podunkfla]

A better thinner for polyester resin is acetone.
EDIT: Hmmm... West System says lacquer thinner may be an even better choise because it evaporates faster. Hafta try that.

I have used it for years this way to soak into rotten or soft wood such as window sills before filling with bondo. It still hardens just fine.

[Juneaudave]

You can thin epoxy, but you might not accomplish what you want...here is a link to West Systems that talks about thinning their product for purposes such as sealing. My gut take on the writeup is "consider the source". Epoxyworks Article

BTW...I do believe that using heat on the wood is a pretty good and safe method. It will draw the epoxy in as it cools.

[Dooner]

If you have a Benjamin Moore dealer around, they have a Polymide Epoxy Clear Sealer/Finish (M36-00/M37). You mix it up with a thinner and it penetrates the wood.
Just a suuggestion.

[Podunkfla]

If you have a Benjamin Moore dealer around, they have a Polymide Epoxy Clear Sealer/Finish (M36-00/M37). You mix it up with a thinner and it penetrates the wood.
Just a suuggestion.

Looks like a good product for the money. I haven't used the clear... But I have used the Polymide Epoxy paint and it is darn good stuff. Last I bought about 9 months ago cost me about $80. for a 2 gallon kit, plus $16. for gal. of thinner/reducer... So, 40 bucks a gallon for epoxy is a pretty good price.

Of course, $20. a gallon for polyester resin is still cheaper; and for something that is going to be painted anyway, seems like a good idea to me? (none of this stuff resists UV radiation, I'm told).

[steve wolverton]

Of course, $20. a gallon for polyester resin is still cheaper; and for something that is going to be painted anyway, seems like a good idea to me? (none of this stuff resists UV radiation, I'm told).

I was thinking polyester resin doesn't need a UV inhibitor, only epoxy resin. I need to dig into this more.

EDIT: "Note that unless a UV inhibitor has been included in the formulation, such as in polyester resin gel coatings, the cured resins are UV sensitive and will eventually weaken with exposure to sunlight and will need protection with a UV blocking surface coating. "

[angib]

a link to West Systems that talks about thinning their product for purposes such as sealing.

I'm reassured to see that they have the same objection to thinning epoxies for sealing that I was taught - it reduces the water resistance of the epoxy.

If you mix in a solvent, when it evaporates it leaves behind tiny voids in the epoxy that are dying to fill with water. With the small gaps between the voids, you create a transmission path for water.

Mind you, we're talking about shortening the lifespan of the wood from 40 years to 'only' 25, or something like that!

Andrew

[Podunkfla]

a link to West Systems that talks about thinning their product for purposes such as sealing.

I'm reassured to see that they have the same objection to thinning epoxies for sealing that I was taught - it reduces the water resistance of the epoxy.

If you mix in a solvent, when it evaporates it leaves behind tiny voids in the epoxy that are dying to fill with water. With the small gaps between the voids, you create a transmission path for water.

Mind you, we're talking about shortening the lifespan of the wood from 40 years to 'only' 25, or something like that!

Andrew

As I've used it to solidify punky wood before I fill the voids with body filler, then paint it; I doubt much water can get to the wood... so it works fine for me. But, Now that I've read that it does seem like warming the resin to 115 degrees is a better way to lower the viscosity. Will try it next time.

[SteveH]

The trouble with warming epoxy is it shortens the pot life dramatically. 45 minute epoxy glue if warmed after mixed, will start to flash in about 20 minutes.

[Guy]

Dear All,

I do believe that M36/38 is the BM product for wood. However, the BM store near me told me last year that they would not recommend or guarantee the product for use on a teardrop because of the constant shrinking and expansion due to use to which teardrops are put to, including exposure to elements and road conditions. They told me to spring for the marine epoxy which they did not sell.

[Arne]

Mike, are you doing the whole tear with cpes, or just the joints?

What will the final finish be....?

[mikeschn]

I went ahead and ordered the CPES. I should have it by Friday.

I was planning on coating the entire tear with it, and sanding it smooth, and shooting it with car paint.

If the CPES alone doesn't get smooth, I'll add a layer of regular epoxy resin.

Mike...