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Priming & Finishing with CPES

A primer (from the Latin "primus," meaning first) is a foundational coat applied to a surface to prepare it for the final topcoat. Its core function is to ensure the durability and effectiveness of the entire coating system.

The most common and essential types of primers, defined by their primary function, are:

Adhesion-Promoting Primer ("Tie-Coat"): Creates a chemical or mechanical bond between the surface and the topcoat. It is crucial for non-porous surfaces (like metal) or problematic ones (like damp concrete).
Porosity-Sealing Primer: Seals porous surfaces (like wood and concrete) to prevent blistering, pinholes, and moisture penetration, which can lead to rot or mold.
Corrosion-Inhibiting Primer: Used on metals to chemically prevent rust from forming beneath the topcoat.
Moisture-Diffusion Barrier: Primarily used in marine environments, it blocks liquid water from entering while often allowing water vapor to escape, controlling internal moisture.
Sanding Primer: Specifically for wood, it glues down loose surface fibers to create a smooth, solid base for a uniform topcoat.

Many modern primers are combination-products that perform multiple functions. For example, Clear Penetrating Epoxy Sealer (CPES) is a multifunctional primer that seals pores, promotes adhesion, locks down wood fibers, and blocks tannin bleed.

For a wood sealer to penetrate and work effectively, there must be empty space within the wood's porosity. This space is unavailable if it is already completely filled with water.

Key Concepts:

Two Types of Water in Wood:Chemically-Bound (Hydrated) Water: Water molecules that attach to the wood's cellulose fibers, causing them to swell. This process is responsible for wood expanding when wet and contracting when dry.Free Water: Water that occupies the empty spaces and pores between the wood fibers. This is the water that must be absent for a sealer to penetrate.
Fiber Saturation Point (~30% Moisture): This is the critical threshold where the wood's fibers can hold no more chemically-bound water. Any moisture content beyond this point exists as free water in the wood's pores.

Practical Application: How to Check Moisture

You can assess a wood's readiness for sealing without a meter by using the "forearm test":

Use the sensitive skin on the inside of your forearm.
Compare the feel of a known dry piece of wood to the wood you want to seal.
Damp wood will feel noticeably cooler and damper to the touch against your forearm.
This method does not work on painted wood.

Before applying a sealer, the wood must be dry enough that its moisture content is primarily below the fiber saturation point, ensuring there is empty porosity for the product to absorb into. The simple forearm test is an effective way to gauge this.

To achieve a longer-lasting finish on a door, proper surface preparation and priming are essential. First, sand the door thoroughly to remove all old finish, starting with a coarse grit (50-grit) and moving to a finer one (100-grit). Remove all dust.

The critical next step is to fully impregnate the wood with Smith's Clear Penetrating Epoxy Sealer. This is not a paint; it is a thin, soaking sealer designed to penetrate deeply. Apply it liberally to one area until the wood stops absorbing it, then move on. The application technique must be adjusted for a vertical door to prevent runs.

After the entire door is saturated, allow the sealer to dry and fully cure for a few days. Once dry, lightly smooth any rough spots with an abrasive pad—no heavy sanding is needed.

The final, crucial step is to apply one more coat of the sealer one to two days before the topcoat. This timing is key because the sealer cures very slowly. Applying the paint or varnish while the sealer is still within its cure window (2-4 days) allows it to finish curing underneath, chemically bonding the topcoat to the wood with the strength of an epoxy glue. This process significantly improves adhesion and dramatically extends the life of any finish.

For a durable varnish finish, start with dry, clean wood. Sand to 220-grit. Use only oil-based stains, allowing 3-4 days to cure. Apply Clear Penetrating Epoxy Sealer (CPES) methodically until the wood is fully saturated and no longer absorbs it. Allow it to cure.

The final, crucial step is to apply a last coat of CPES. Do not sand it. Apply the first coat of varnish the next day, while the CPES is still curing. This allows it to chemically bond and glue the varnish to the wood with epoxy strength.

The key to UV protection is final dry film thickness, not number of coats. Budget a pint of varnish for every 5-10 square feet to ensure adequate coverage.

For a successful varnish job, focus on achieving a sufficient dry film thickness, as this is the primary factor determining its longevity and protection against UV damage.

A good rule is to budget **one quart of varnish for every 20 square feet** of surface. The number of coats is less important than the total amount of material used. Avoid heavy sanding between coats, as it removes crucial film thickness; a light sanding to a matte finish is sufficient.

Application technique is critical:
* On vertical surfaces, thin the varnish with a solvent reducer to prevent drips and sags, applying multiple thinner coats.
* On horizontal surfaces, avoid applying too thick a coat, as it can skin over and remain gummy underneath, leading to wrinkles.

Always practice on scrap wood first to determine the right thinning and brushing technique for your specific varnish and conditions. Use proper brushing strokes to blend edges and eliminate brush marks.

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CPES also sold as MultiWoodPrime) is a penetrating epoxy sealer for wood preparation and restoration. There are two goals when staining wood: to even out the tone or to enhance the natural grain. For both, use only *oil-based stains*; avoid water-based stains or those with dyes, as they can fade.

The correct sequence is crucial:
1. Old/Restored Wood: Sand, apply CPES first to consolidate the wood, lightly sand again to expose the fibers, apply the stain, and let it cure for 4 days. Finish with another coat of CPES and the topcoat.
2. Even Color (New Wood): Follows the same sequence as for old wood. The sandpaper grit (coarser = darker) controls the tone.
3. Grain Highlighting (New Wood): To enhance porosity, sand well and apply the stain before CPES. The stain will accumulate in the pores, highlighting the grain. Let it cure for 4 days before applying CPES and the topcoat.

CPES should always be the final adhesion primer before the topcoat, bonding it to the wood with epoxy strength.

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Restoration with CPES

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Restoring a wood door is often more cost-effective than replacement. The primary causes of failure are rot (typically on the bottom edge), weather damage (water, temperature causing cracks and finish lifting), and sunlight degradation (breaking down clear finishes).

The restoration process relies on key products and methods:

Assessment & Prep: Remove the door and excavate all deteriorated wood, often focusing on the porous end grain of the stiles.
Wood Consolidation: Impregnate the damaged wood with Clear Penetrating Epoxy Sealer (CPES). This stabilizes the remaining fibers and creates a solid base for repair.
Filling: Use an epoxy filler to rebuild missing structure and fill cracks.
Finishing: After final sanding, re-prime with CPES to ensure ultimate adhesion before applying a high-quality topcoat (paint or varnish).

CPES is critical as it bonds wood fibers, seals porosity, and acts as a superior adhesion primer, gluing the new finish to the restored wood. Avoid chemical strippers that can leave residues; sanding or heat scraping are preferred for finish removal. For longevity, ensure an adequate dry film thickness of the topcoat to protect against UV and moisture.

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Restoring rotted wood is a cost-effective alternative to full replacement. The process begins by removing all loose, flaking paint, ideally with a heat gun and scraper or a sander, avoiding chemical strippers that can leave residues.

Probe the wood with a pick to assess soft, deteriorated areas. Remove the worst of the rot, but stable, slightly soft wood can often be saved. The key to a permanent repair is saturating ALL the remaining wood with Clear Penetrating Epoxy Sealer (CPES). This unique product penetrates deep into the wood fibers, killing fungal spores and bonding the damaged wood into a solid substrate. It prevents future rot from recurring behind the repair.

Once the wood is impregnated and the CPES has cured, the missing sections are rebuilt with an epoxy filler. Finally, the restored wood is primed and painted. This system, using an oil-based primer and a latex topcoat, creates a finish that lasts for decades, protecting your investment for a fraction of the cost of replacement.

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Additional Repairs & Applications

To achieve optimal performance from two-component products like epoxies, adhesives, or sealants, it is crucial to mix the parts exactly in the correct proportions and ensure thorough and homogeneous mixing.

Why?

The molecules of Components A and B are designed to react in a specific ratio (e.g., 1:1).
Incorrect proportions leave unreacted molecules, resulting in a final material that is weaker, softer, or sticky.
Inadequate mixing creates pockets with excess A or B, leading to spots that do not cure properly.

How to Mix Correctly:

For pastes (e.g., fillers): Use the color difference between the components as a guide. Mix, scrape, and fold the compound until the color is uniform, with no streaks.
For liquids (e.g., glues): Measure equal volumes. Mix thoroughly in a first container, transfer everything to a second container, and mix again. Repeating for a third container ensures no unmixed portion is left behind.

Thorough mixing in the correct proportions is key to ensuring the product cures with the full strength, durability, and properties it was formulated to achieve.

To estimate glue quantity, calculate based on surface area and glue-line thickness. The core formula derives from volume: 1 gallon = 231 cubic inches. A 1/64-inch thick layer covers ~100 sq ft per gallon, while a 1/32-inch layer covers ~50 sq ft.

Key factors reduce actual coverage:

Wood Porosity: Absorbs glue, varying by species and grain. Dense woods use less; porous woods (e.g., teak) can halve coverage.
Squeeze-Out: Excess glue ensures joint integrity but creates waste. Reclaiming squeeze-out minimizes waste.
Surface Flatness: Rough or uneven surfaces increase glue-line thickness, reducing coverage.

For efficiency:

Apply glue to both surfaces and allow brief absorption before assembly.
Use a long pot-life glue (e.g., Smith's Dead-Slow Epoxy Glue™) to facilitate reuse of squeeze-out.
Expect practical coverage of 50–300 sq ft/gallon, depending on wood type and technique.

Stucco cracks due to ground movement and building settlement, which are ongoing seasonal processes. Traditional repairs with cement or caulk fail because they cannot stretch or bond adequately to withstand this movement.

The effective solution is a mechanical approach: widen the crack into a V-groove. This reduces the strain on the filler material during movement. For instance, a 1/16" crack movement in a ½" wide groove represents only 12.5% elongation, which most sealants can handle.

Procedure:

Prime: Clean and dry the area. Apply Smith & Co. Damp Concrete Primer (DCP) to the V-groove to strengthen the stucco and ensure chemical bonding. Apply it carefully with upward brush strokes to avoid runs.
Caulk: Once the primer is touch-dry (same afternoon), fill the groove partially with a high-quality, flexible sealant (e.g., 3M 5200). Smear it forcefully against the groove walls to ensure adhesion, then fill completely.
Blend: While the caulk is still tacky, press fine sand or gravel into its surface. Once cured, painting over this will match the surrounding stucco's texture, making the repair invisible.

This method addresses the root cause—ongoing movement—by accommodating it mechanically, rather than trying to resist it with a rigid patch. Proper priming and adhesion are essential for long-term success.

To seal concrete blocks effectively, start by ensuring the surface is smooth. Grind down any bumps along mortar joints using a 36-grit aluminum oxide disc. Thoroughly clean the surface of dust, debris, and efflorescence with a brush and vacuum.

Once the surface is clean and dry, apply Damp Concrete Primer (DCP) in the morning. Mix the concentrate with water to form a tan emulsion and apply it with a roller using upward strokes. This primer wets the surface and penetrates the pores, preparing it for the filler.

By the afternoon, when the primer is no longer sticky, apply Fill-It Epoxy Filler. Force it into all holes and voids using a squeegee, working in multiple directions to ensure complete coverage. Coverage typically ranges from 30–100 sq ft per gallon, depending on block porosity.

Work efficiently, as the filler has a pot life of about one hour. Re-prime any areas not filled the same day. This two-step process—priming with DCP and filling with epoxy—creates a durable, waterproof seal that prevents future moisture intrusion.

For strong wood glue joints, proper surface preparation and technique are crucial. Always sand all surfaces to remove potential mill glaze and ensure clean wood is exposed. Apply a liquid epoxy adhesive to both surfaces and allow it to soak in briefly to prevent the wood from absorbing all the glue from the joint later.

Clamping must be done correctly: use only enough pressure to bring the pieces into contact and squeeze out excess glue—excessive force creates starved joints. Avoid bending pieces to fit, as spring-back forces can exceed wood's shear strength.

Be mindful of wood properties: oily or acidic woods require specially formulated epoxies. Never use solvents to clean surfaces before gluing, as they absorb into the wood and weaken the bond. For very porous woods, pre-treat with a penetrating epoxy sealer.

Finally, always mix two-part adhesives thoroughly and observe safety precautions to avoid skin contact and potential allergies.

Smith & Co. provides a durable, non-porous flooring system for commercial and industrial spaces, particularly in food-related environments. The process ensures a coating that permanently bonds to concrete and withstands heavy use.

Key Steps:

Surface Preparation: Old concrete must be chemically cleaned with Permanent Concrete Sealerto remove deep-seated oils and contaminants. This sealer also permanently blocks liquid water and efflorescence while allowing vapor transmission. New concrete requires abrasive blasting or acid etching to expose silica for proper bonding.
Priming: Apply Damp Concrete Primer (a waterborne polyurethane) to the damp or dry, sealed concrete. This creates a permanent chemical bond to the mineral surface and acts as a universal glue for subsequent topcoats.
First Coat & Repair: Apply High-Build Epoxy Paint. Then, use Fill-It Epoxy Filler to level pits, rough spots, and create a sanitary cove at the wall-floor junction. A polyethylene sheet can be used to achieve a perfectly smooth surface without sanding.
Final Coats: Apply two additional coats of High-Build Epoxy Paint for a complete, seamless, and chemical-resistant finish. Allow 48 hours for full cure before subjecting to heavy traffic.
Slip Resistance: For critical areas, embed blasting sand into the wet epoxy paint and lock it in place with a final coat.

This system creates a monolithic, easily cleaned surface that health inspectors approve. Its longevity is ensured by the powerful chemical bonding of each layer, from the concrete sealant to the final topcoat. Repairs are straightforward by sanding and recoating.

GRP hull blistering ("osmosis") has two fundamental causes:

Poor Workmanship: The use of polyester resin, which is inherently unstable in water. Polyester is an ester, and a chemical reaction called hydrolysis causes it to slowly decompose back into acid and base components. Cheap manufacturing (e.g., chopper guns) creates microscopic voids and leaves water-soluble contaminants (like methyl ethyl ketone) in the laminate, accelerating this process and creating osmotic pressure that forms blisters.
Water Intrusion: Water permeates the laminate, triggering decomposition and blister formation.

The Solution: A Barrier Coat System
The core principle is to drastically reduce the water concentration in the laminate. This is achieved with a specialized moisture-diffusion barrier coating (e.g., Smith & Co.'s High-Build Epoxy Paint) on the hull's exterior, combined with adequate ventilation in the bilge. This system allows any moisture that does get in to evaporate out faster than it enters, keeping the laminate dry and stopping the chemical reaction.

Key Repair Steps:

Assess Laminate: In severe, recurring cases, test a drill sample with XRF spectroscopy to check for cost-cutting mineral fillers (e.g., talc, limestone) that guarantee failure.
Remove Damaged Material: Grind out all blisters to sound laminate. For severe decomposition, complete gelcoat removal may be needed.
Clean & Dry: Rinse the hull to remove decomposition residues. Dry thoroughly using moving air (fans), not just dehumidifiers. Drying time is typically weeks, not months.
Seal Laminate: Saturate the porous, exposed laminate with Clear Penetrating Epoxy Sealer (CPES) to consolidate it and block pathways for water.
Apply Barrier Coats: Apply multiple contrasting coats of a high-build epoxy barrier paint. Sand between coats and use an abrasive pad to break off any microscopic glass fibers that could act as water wicks.
Fill & Fair: Use an epoxy filler to fair the hull, then apply final barrier coats.
Finish: Apply antifouling paint.

This technology, developed in the 1970s, creates an impermeable shield that prevents water from reaching the laminate, allowing repaired hulls to last for decades. The success depends entirely on correct workmanship and using the right chemical systems.

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