Teardrops n Tiny Travel Trailers

How much CPES did those of you who have used it, need to coat an average sized (say 4X8 cubby) ???

I don't want to buy more then I will need this time around as I have a strictly tight budget.

The Rott Doctor let me know how much I needed when I called them. Their customer service is outstanding!

I bought the 2 gallon kit to cover a 9'long by 5'wide by 5'high TD. I did 2 heavy coats on the TD and still have close to a half gallon left over. Hope that helps.

Mike

Marck, Here are some results I post a while back on the coverage I got.

On Radiata Pine and Okoume plywood it only took two coats to completely seal it. On a test piece, three coats completely filled the grain, two coats 95% filled the grain. If I wanted lots of depth to a finish, I would start with two coats of CPES to seal the wood, then switch to normal epoxy to build thickness.

Different woods have different absorption rates. The Radiata Pine sucked up three times as much as Okoume did. A 24 sq ft area of Radiata Pine took 18 oz on the first coat and 6 oz on the second coat. A 49 sq ft area of Okoume took 20 oz on the first coat and 6 oz on the second coat

My baltic birch plywood floor took 3 coats of CPES to seal.

So here's a question to go along with all this:

How many square feet will a gallon of CPES cover?

schaney wrote:...then switch to normal epoxy to build thickness...

What "regular" epoxy do you use to build thickness?

West System
System 3
System 3 Silver Tip
MAS
I have also used the house brand from Fiberglass Coatings.

Sources: Fiberglass Coatings, Jamestown Distributors, Boatbuilder Central, etc.

Things to consider with epoxy:

Epoxy doesn't have a lot of UV protection. Cover it with a clear-coat auto-finish like Imron or Alwgrip.

The slower the cure, the harder the finished product.

The more resin/hardener the harder the finished product.
West System is 5 to 1 - very hard, difficult to mix in small quantities (buy the mixing pumps)

Most of the others are going to be 2 to 1 or even 1 to 1.

Stay away from 5 minute epoxies EXCEPT to tack things in place for later lamination using real epoxy.

Jamestown Distributors also sells a laminating epoxy from Smiths (the people who make CPES) but I can't find any strength-test data on it.

my other very long-winded post on epoxy can be found at this link.

I used just over 1 1/2 gallons for a 5x10 woody.

stomperxj wrote:How many square feet will a gallon of CPES cover?

From their website. I found it to be rather accurate. The first coats on dry, sanded wood will take more than subsequent coats.

The coverage of CPES™ will depend entirely on the surface to which it is being applied. On rotted logs in log homes it can take a gallon every three to four feet to soak bad wood, yet for surface application on clean, sanded hardwood it can go about 300 sq. feet per gallon (7 sq. meters/liter). In any application of CPES™ the key is to allow the wood to absorb all that it can. It is especially important that CPES™ be applied generously to edges and end-grain areas because this is where the rot likes to get started.

To determine how much CPES™ you might need, use your best judgment based on the type, finish and condition of the wood. On new wood you can plan between 200 and 300 sq ft per gallon (5-7 sq meters/liter), although on rough, porous woods such as Cedar the coverage can go down to 100 sq ft per gallon (2.5 sq meters/liter). If the wood is rotted or deteriorated, or if there are large areas of end-grain, then it's pretty much a guess. Just look at the area that is going to be treated, imagine how much water it would absorb if generously applied, and that's going to be close to the amount of CPES™ you will require.

And remember -- the drier the wood the better the absorption. If you press the wood and water emerges then it's too wet for CPES™ treatment. If it's slightly damp application is okay, but you should always try to apply CPES™ to wood which is in the normal range, 12% to 20% moisture in average humidity conditions.

theoretically, the first coat does most of the work. It soaks in and hardens. The second coat helps fill the dry spots and grain, but given the second coat does not take nearly as much to do, it it is not doing as much work as the first coat, but it does help with those spots where the first coat was applied a bit too lightly. a second coat is good insurance.

I bought the 2 gallon kit and have a lot left over, probably about 1/3 of the original kit.

Stomperxj, I used West Systems epoxy.

As Palnovets reply shows, it depends Using my results above, a gallon would cover 128 sq ft for an initial cover on pine / fir plywood. Then the second coat on the same 128 sq ft would take about a quart.

Ok let say I get the 2qt CPES and it does the first coat ok. Then i am doing the second coat and run out after only getting the roof done.

Is thier a time limit or a wait time where I can wait and order another 2 qt have it shipped and then finish the second coat.

Starting to enjoy this again.