Anyone ever use Rot Doctor's CPES?

[gunner1]

Thinking of using this to seal my new floor before final installation. It says it'll cover between 200-300 square feet per gallon. It also completely seals the wood from water. Any info/tips?

 

[Coors]

Re: Anyone ever use Rot Doctor's CPES?

After a lot of on-line reading, and talking to people---not that good.
Only for surface area rot.
During my stringer re-build, I diluted some MAS epoxy, and tested it-same thing, not good at penetration.

 

[qaztwo]

Re: Anyone ever use Rot Doctor's CPES?

Yes I used it when I redid my stringers, floor, and transom. For the price was not impressed with the penetration that in provided. When I did the transom applied to entire transom. installed transom, when dried cut out for outdrive. When I examined the piece of wood that was cut out the cpes had only gone into the wood 1mm to 2mm. I believe resin by itself would have done the same.

 

[ondarvr]

Re: Anyone ever use Rot Doctor's CPES?

From what I've read about it these results are typical, and not just for this product, but for most, if not all penetrating type products. Epoxy already bonds very well to dry wood and rot has little to do with penetration, it has more to do with encapsulation (as in no water getting to the wood). As you add solvents to epoxy to lower the viscosity, you also reduce it's strength and water resistance, so it's a real trade off that really doesn't have a big benefit.

 

[seven up]

Re: Anyone ever use Rot Doctor's CPES?

Never used it. I make thinned epoxy with laquer thinner.

 

[Robj]

Re: Anyone ever use Rot Doctor's CPES?

I have some Git Rot which is the same type of thing. The literature that came with it says that it will penetrate about 1/2 inch. But based on what you guys are saying, it sounds like it is not he case. I have some wood that I was not able to replace, it was solid but was going to treat it with CPES as a preventative measure. Sounds like that is a waste of time.

Have a great day,

Rob.

 

[gunner1]

Re: Anyone ever use Rot Doctor's CPES?

How far does the stuff really have to penetrate to make the wood watertight? I can't see much water reaching the plywood anyways since I'll be putting marine vinyl over it.

 

[Coors]

Re: Anyone ever use Rot Doctor's CPES?

I have some Git Rot which is the same type of thing. The literature that came with it says that it will penetrate about 1/2 inch. But based on what you guys are saying, it sounds like it is not he case. I have some wood that I was not able to replace, it was solid but was going to treat it with CPES as a preventative measure. Sounds like that is a waste of time.

Have a great day,

Rob.

Epoxy and cloth.

 

[Coors]

Re: Anyone ever use Rot Doctor's CPES?

Epoxy and cloth. That seal it and lasts.

 

[BillP]

Re: Anyone ever use Rot Doctor's CPES?

When I first heard about this it sounded like the best thing since sliced bread...that was back in the 1960s. I immediately tried what is still a well known name brand (the only one back then) penetrating epoxy on a piece of very rotten mahogony trim. The wood was so punky it could be dug out with my fingers. So I drilled holes in the piece as printed on the instructions and applied the stuff. Later I cut samples to see how well it did...most places were 1/8" deep or less. I've tried this with several brands and done it with my own mixes. All had the same results. "Penetrating epoxy" is voodoo science in my opinion and at best a cosmetic fix. What nobody mentions is the resin traps air and makes penetration more difficult or impossible. I had bubbles appear but most wouldn't release from surface tension unless popped by me.

bp

 

[oops!]

Re: Anyone ever use Rot Doctor's CPES?

bonds very well to dry wood and rot has little to do with penetration, it has more to do with encapsulation (as in no water getting to the wood).

i think this is an exellent point that i hope everyone got.....

we just gotta make sure no water gets in there......(i know this is impossible.....but as best we can)

 

[seven up]

Re: Anyone ever use Rot Doctor's CPES?

I would guess that the CPES would work very well on the end grain of plywood.

Especially if you are using the box store quality of pressure treated ply. The endless number of voids and low quality inner plies could benefit from treatment.

From using my own concoction it just disappears into the endgrain. Any void that is sealed up is an improvement as there is less chance of water vapor penetration.

Enjoy

 

[gunner1]

Re: Anyone ever use Rot Doctor's CPES?

OK how about something like Thompson's WaterSeal Advanced? Remember, I'm going to be putting vinyl over the plywood anyways so there will be little moisture if any reaching the plywood.

 

[oops!]

Re: Anyone ever use Rot Doctor's CPES?

i have not used thompsons water seal.....

but from the foul language ive read on here...(&%#&^$#@^)......

I assume there might be a better product for boat restoration....

 

[ondarvr]

Re: Anyone ever use Rot Doctor's CPES?

Thomsons water seal if junk (IMO) for this type of use. There's nothing wrong with coating your plywood with epoxy, it works well.
You asked about penetrating epoxies like CPES and what people though or knew. The penetrating part is the problem, you (they) add a great deal of some type of solvent to reduce the viscosity of the epoxy, this makes it weaker and less water resistant and really doesn't help with deep penetration. So just use regular unthinned low viscosity epoxy and take advantage of it's full strength.

P.S. Like others already said, a layer of cloth with the epoxy will make a much better water barrier than just a layer of epoxy and the vinyl flooring won't do much to keep water out.

 

[seven up]

Re: Anyone ever use Rot Doctor's CPES?

If you've ever used thinned epoxy then it's a waste of time to write that it disappears into the wood as you will already know.

Try plywood laying vertical with the thinned stuff and next to it try another with unthinned epoxy. The unthinned epoxy will drool down onto the wax paper and the thinned goes into the wood.

There are cases where you do not want to use cloth and epoxy. Thinned epoxy will provide the basic starting point. Nowhere did anyone write that the CPES or thinned epoxy is to be used as a laminating agent with cloths or claim equivalent properties.

I would definitely recommend CPES or thinned epoxy on marine fir plywood that I wanted to paint, only for the benefit of stabilizing the grain from checking and lifting the paint off.

IF you want cloth on the cockpit sole, use dynel. It will leave a non-skid surface after wet out and cure.


Enjoy

 

[Coors]

Re: Anyone ever use Rot Doctor's CPES?

When I first heard about this it sounded like the best thing since sliced bread...that was back in the 1960s. I immediately tried what is still a well known name brand (the only one back then) penetrating epoxy on a piece of very rotten mahogony trim. The wood was so punky it could be dug out with my fingers. So I drilled holes in the piece as printed on the instructions and applied the stuff. Later I cut samples to see how well it did...most places were 1/8" deep or less. I've tried this with several brands and done it with my own mixes. All had the same results. "Penetrating epoxy" is voodoo science in my opinion and at best a cosmetic fix. What nobody mentions is the resin traps air and makes penetration more difficult or impossible. I had bubbles appear but most wouldn't release from surface tension unless popped by me.

bp

Yep

 

[Coors]

Re: Anyone ever use Rot Doctor's CPES?

I would guess that the CPES would work very well on the end grain of plywood.

Especially if you are using the box store quality of pressure treated ply. The endless number of voids and low quality inner plies could benefit from treatment.

From using my own concoction it just disappears into the endgrain. Any void that is sealed up is an improvement as there is less chance of water vapor penetration.

Enjoy

Why not use full strength, and be done with it? All that solvent went into the air, not the wood ( it carried hardly any resin in).

 

[Lou C]

Re: Anyone ever use Rot Doctor's CPES?

The stuff does have its place, like in a project where you can't really rip everything out (the best if you can) but you want to halt existing rot and build up what is there. I fixed some rot on my back porch about 5 years ago, cut out as much as I could, then treated all the wood with the CPES. Next made patch panels and used rot docs epoxy filler and then used their epoxy resin on top of the new wood. It still looks good, 5 years later, in a damp climate.
If you look at some of the test panels on their site, the stuff does work as far as preventing plywood from delaminating. But for most deck repairs you are going to use resin anyway so at that point it may not matter. Wooden boat guys love the stuff though.

 

[JustJason]

Re: Anyone ever use Rot Doctor's CPES?

whatever you put over the wood... marine vinyl or whatnot... your going to get a layer of moisture inbetween the vinyl and the wood anyways. It will get in there!!
How bout this....
take 3 samples of the wood your using in the boat and set them aside (scrap wood)
get some good high quality polyester fiberglass.(not the stuff at autozone or home depot)

Rough up your wood with 36 grit on a dual action or orbital sander. Mix up 3 batches of glass in 3 containers according to the directions on the box... in container 1 do not thin it. in container 2 thin it slightly with acetone or whatever the product calls for to thin it... in container 3 thin it a whole bunch.
let it cook off overnight.
on day 2, sand the pieces with 150 grit to rough it up, blow off and wipe down with cloth lightly damped with acetone.
mix up 1 batch of glass not thinned... and go over all 3 test pieces again...
let it cook off another night
day 3.... run all 3 pieces through the saw and see which one you like better.