Senseal Multiprimer (CPES)

[srohara]

Hi

I was wondering if anyone has use a product called Senseal Multiprimer CPES. I was wanting to use the product to prevent wood rot in my joist in a deck that i am building. Does anyone know about coverage rates for the product. If anyone has used the product i would like to know what they thought of it. Any info would be great.

Thanks
Scott

[hansp77]

It has a near religious following in certain wooden boat circles (and then on the other side ore the people who think it and all other penetrating epoxies are rubbish)
Out of all the penetrating epoxies, it is probably the most popular- and expensive.

I haven't actually used CPES (Smith's Clear Penetrating Epoxy Sealer), but a couple of other penetrating epoxy brands- and continue to do so on my boat.

Yeah, it (penetrating epoxy) is good stuff IMHO.
The way to put it on is to saturate the timber, especially end grain, let cure, sand, then saturate again. Repeat untill it will take in no more.


Alternatively and a bit cheaper, you can thin your own epoxy (lacquer thinners or epoxy thinners work well) or just heat up raw epoxy which will thin it and allow it to penetrate.

If you heat up raw epoxy for penetration then it is argumentatively better than thinned epoxy. Thinning epoxy degrades it, and makes it something less than totally waterproof- as the solvent evaps off it leaves many little microscopic holes (this is why re-applying and re-applying is preferable).

check out West System.
http://www.westsystem.com/
they have a lot of good advice and studies regarding epoxy.




There are epoxy-based products specifically designed to penetrate and reinforce rotted wood. These products, basically an epoxy thinned with solvents, do a good job of penetrating wood. But the solvents compromise the strength and moisture barrier properties of the epoxy. WEST SYSTEM epoxy can be thinned with solvents for greater penetration, but not without the same compromises in strength and moisture resistance. Acetone, toluene or MEK have been used to thin WEST SYSTEM epoxy and duplicate these penetrating epoxies with about the same effectiveness. If you chose to thin the epoxy, keep in mind that the strength and moisture protection of the epoxy are lost in proportion to the amount of solvent added.
There is a better solution to get good penetration without losing strength or moisture resistance. We recommend moderate heating of the repair area and the epoxy with a heat gun or heat lamp. The epoxy will have a lower viscosity and penetrate more deeply when it is warmed and contacts the warmed wood cavities and pores. Although the working life of the epoxy will be considerable shortened, slower hardeners (206, 207, 209) will have a longer working life and should penetrate more than 205 Hardener before they begin to gel. When the epoxy cures it will retain all of its strength and effectiveness as a moisture barrier, which we feel more than offsets any advantages gained by adding solvents to the epoxy.