Clear Penetrating Epoxy Sealer™ (CPES™) consists of a tough, flexible resin system in a solvent blend which dissolves the sap, oil and moisture found in wood. The resin system is derived from natural wood resin and develops a chemical adhesive bond to the wood fibers themselves.
The wood is strengthened while allowing normal expansion and contraction with changes in temperature and humidity.
When repairing wood that has mild dry rot, the CPES will migrate along the abnormal porosity which dry rot fungus creates within the wood, as long as it continues to be fed in. Impregnation of wood with CPES changes the cellulose of wood (which fungi and bacteria find tasty and easily digestible) into epoxy-impregnated cellulose which resists further attack by fungi and bacteria while reinforcing the wood, accomplishing restoration.
Paint or varnish will last longer because the paint has a strongly attached, chemically compatible surface to bond onto.

The long working time (pot life) of these products mean they will retain their penetrating and moisture-dissolving ability for more time.
Read and follow application instructions. Keep rain or dew away from areas being treated with CPES until solvents have evaporated out of the wood. This will take at least a day and may take a week or more, depending on the extent of deterioration, how deeply the CPES soaked in and the temperatures day and night.
Application may be by brush, roller or immersion. Spraying is not recommended as a portion of the solvent component will evaporate in transit, and it is important that the product be applied to the wood in the same formulation furnished originally. When applying by roller on a vertical surface, hold the roller only horizontally and slowly roll only upwards. When treating rot inside sound wood, drill a hole that intersects the rot, glue a funnel in the hole, and use the Cold Weather Formula to impregnate the region. Allow sufficient time for solvents to diffuse and evaporate out of the wood before applying fillers or glues. Removing paint from all sides of wood to be treated speeds solvent evaporation, as does moving air.
CPES is also a consolidant for old, crumbly concrete or mortar between bricks, and is an essential component of effective osmosis blister treatment on fiberglass boats.
Our Epoxy Cleanup Solvent. will clean up any epoxy product before it cures. Once cured, no clean-up solvent is effective.

Working in cooler weather?

Use our Cold Weather Formula

The Cold Weather Formula™ of Clear Penetrating Epoxy Sealer was developed because sometimes repairs such as restoration of deteriorated wood, repair of osmosis-damaged fiberglass boats, and/or adhesion-promoting priming for sealants or coatings must be done in the winter.

The particular kind of resins that must be used in Clear Penetrating Epoxy Sealer in order to obtain all its usual performance features, which have made the product famous, do not cure well below about 50° F and essentially stop curing by 40° F. This is a normal characteristic of these products, and has been well known to chemists for half a century. If used in cold weather, after a few days they cure in an incorrect manner and do not develop optimum properties in the wood.

Early in 1991 the genius in the research department of Smith & Co. discovered the fundamental reason why this is so, and discovered the Dual Synergistic Catalyst which makes it possible for these resin systems to develop a full and predictable cure at temperatures down to 28° F, slightly below freezing!

The entire formula was redesigned to take advantage of this new technology. The new formulation behaves essentially the same in freezing weather as the Warm Weather Formula™ does in moderate weather. The Cold Weather Formula was designed to absorb as much water as the existing system does from wood or osmosis-damaged fiberglass laminate, and in addition to dissolve the ice crystals that form in damp materials subjected to below-freezing conditions.

The product line was further improved in 2001 when the solvent formulation was upgraded to give a 50% increase in moisture-dissolving capabilities.
Clear Penetrating Epoxy Sealer will prevent freeze-thaw damage to concrete. This surprising performance was discovered by a customer in Finland and verified by the National Testing Institute.

The Cold Weather Formula of Clear Penetrating Epoxy Sealer mixes one-to-one by volume as does the Warm Weather Formula. Once mixed, it is recommended that the product be used within its "pot life", although it will be fluid for much longer.

The Cold Weather Formula of Clear Penetrating Epoxy Sealer (CPES) was designed to be used in the temperature range of 28° F - 65° F. The table of pot life and full cure times on the next page illustrates this.

It is a necessary part of the wood restoration process that the solvents be allowed to evaporate out of the wood before paint or filler is applied. The solvent blend in the Cold Weather Formula evaporates about as fast in cold weather as the solvent blend in the Warm Weather Formula does in warm weather.

The solvent blend of the Cold Weather Formula has a milder odor, as well as evaporating about six times faster. These features allow restoration work to be completed sooner and to be done in the winter, when most products do not work properly.

Restoration of wood inside a house, such as in a bathroom, a door threshold or the inner part of a window sill, should be done with the Cold Weather Formula rather than the Warm Weather Formula when the house is occupied, due to the much milder odor and more rapid solvent vapor dissipation of this version.

Nighttime temperatures are usually much less than daytime temperatures and so night provides less progress towards full cure than day. This makes the Cold Weather Formula valuable when the daytime temperatures are in the 50° F ~ 60° F range and/or night temperatures are in the 30° F ~ 40° F range.

© copyright 1972 - 2014, The Brain Trust, a California irrevocable trust, reprinted with permission

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