What is "CPES"?

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bobinpowayca
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What is "CPES"?

Postby bobinpowayca » Mon Feb 23, 2015 2:26 pm

Hi, I'm building the Geronimo, getting close to finishing planking the hull; next I'll be encapsulating the hull, fiberglassing it then painting with a 2-part polyurethane (probably gonn a brush it vs. spray).
Can someone tell me what "CPES" is? I see it mentioned a lot on the forum and I'm wondering what it is and for what purposes you'd use it. This will likely be my last build and I want to use only the best materials, cost isn't a problem. Thanks, bob
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Bob
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Built the Glen-L 17 (1988), Geronimo under construction (2013)
PBR support (1968)

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chugalug
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Re: What is "CPES"?

Postby chugalug » Mon Feb 23, 2015 3:59 pm

:D According to the Rot Doctors Clear Penetrating Epoxy Sealer(CPES) it is the leading product for treating rotted wood.However it can be used as a preventative too.The resin is derived from wood and besides alcohol the are other organic solvents added so they can "carry the mix into the wood" then the carriers can evaporate out of the wood and leave the resin to harden up and seal up the pores yet stay flexable.The fumes are pretty strong so a respirator is highly recommended unless using outside.The only spraying method recommended is the hand operated spray bottle.Otherwise use a brush.It's really thin so soaks in fast -keep applying until wood won't soak up any more.Let cure for a few days.I put 4 coats of CPES on my 18 ft hull before putting 5 thin epoxy with cloth on hull.Still had about 1gal left (from 2 gal kit)So put that in hand sprayer and sprayed all the really hard to get at spots after the hull was turned-Waiting on another 2 gal kit to soak down insides.
Working on regular-sized Bo-Jest


"If it's not crooked,It's not mine

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chugalug
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Re: What is "CPES"?

Postby chugalug » Tue Feb 24, 2015 5:40 am

:D I got the cold formula from rots .I got the shop up to about 80,then turned off all thing that might cause a spark.Not sure if fumes would ignite.From the looks of your shop,I would check into the stuff that Jamestown Distributers has-they claim no fumes but can be thinned out with acetone.I haven't worked with that yet am tempted tho. :D
Working on regular-sized Bo-Jest


"If it's not crooked,It's not mine

cusoak
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Re: What is "CPES"?

Postby cusoak » Tue Feb 24, 2015 8:00 am

I have used CEPS a lot in restoring antique Mahogany boats and on my Zip build. You will need to put on more than one coat for it to do it's job.
You will know that you have enough on when it becomes shiny. Each coat soak's into the pores of the wood and then it sort of glues everything together.
Great stuff for sealing wood. You will need to sand after words to get a smooth surface.
Jeff

bobinpowayca
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Re: What is "CPES"?

Postby bobinpowayca » Tue Feb 24, 2015 9:47 am

Thanks Jeff & Chug. I think I used some of this stuff (marketed as a different name) as a pre-treatment when I was doing dry-rot repair on my house, very expensive at the depot.
I understand - this would be a good first couple of coats on the bare wood because being thin it will penetrate the wood better than regular epoxy resin. Same principle as using very thin (reduced) initial coats of varnish, right?
So probably I will use CPES prior to encapsulating, light sanding between coats.
Is there any issue with epoxy resin adhering to a CPES coated hull, i.e., should it be washed (water or ammonia, e.g.), before coating with resin? Thanks guys, Bob
Bob
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Built the Glen-L 17 (1988), Geronimo under construction (2013)
PBR support (1968)

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Bill Edmundson
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Re: What is "CPES"?

Postby Bill Edmundson » Tue Feb 24, 2015 11:25 am

I did a test on new wood. I did part of the same piece of wood with CEPS and part with regular epoxy. I cut the sample and sanded the edge. I couldn't tell a significant difference. I then sanded at a sharp angle. there was a fine curled edge on both. But, no difference.

I'm sure this will ruffle some feathers. So, use what you feel good about. I just go for regular epoxy.

Bill
Mini -Tug, KH Tahoe 19 & Bartender 24 - There can be no miracle recoveries without first screwing up.
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chugalug
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Re: What is "CPES"?

Postby chugalug » Tue Feb 24, 2015 12:03 pm

:D When I put CPES on my hull,I was just following opinions of others that used it.Sure,the CPES is expensive(over 100$ a gal)comes in 2 gal kit.Rots was a little cheaper than Smith's.Looking at the picture on cans -looked the same.Figured I would try it.Can't put it on later after epoxing. Stuff really stinks.the shop reaked for a few days.Regular epoxy isn't cheap either.I didn't have problems with blush but washed hull with soap and water anyway,then dryed and epoxied after hull was dry.I didn't sand between coats of cpes,just light sanding after 2 day cure of it.
Working on regular-sized Bo-Jest


"If it's not crooked,It's not mine

bjfrater
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Re: What is "CPES"?

Postby bjfrater » Wed Feb 25, 2015 2:20 am

I have to agree with Bill on this one.
I spoke to the guys West System. They told me that using CEPES is not necessary if you are encapsulating using their 105 system products, they provide all the protection necessary. Basically you would just be adding weight by adding CEPES first and no further benefit.

Its each builders call however I decided to save the money, time and risk of exposure to dangerous chemicals.


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