• For high-strength bonding & repairs
• Easy to spread, sag-resistant formula
• Fast-setting, resists shrinkage & cracking

TotalBoat Polyester Structural Repair Putty is a 2-part, high-strength, fibrous polyester structural bonding and marine repair putty that contains long strand milled glass fibers for strength and dimensional stability. This product can be used above or below the waterline. The required MEKP catalyst is included.

Cleaner / Surface Preparation Solvent

Acetone

Cleanup

Acetone. Once cured, it must be removed mechanically.

Catalyst

MEKP (methyl ethyl ketone peroxide), 9% active (included with purchase of TotalBoat Polyester Structural Repair Putty)

Thinner / Reducer

Do not thin this product.

Colorants / Tints

Colorants and tints are not commonly added but can be added at a small percentage if they are compatible with polyester resin.

Cure Methods (Not Included)

Paraffin wax, polyvinyl alcohol, vacuum bagging

Exothermic Reaction

The cure of TotalBoat Polyester Structural Repair Putty is an exothermic reaction and will generate heat. It is not uncommon for a mass of catalyzed polyester resin left in a mixing cup to reach 200–300°F during the cure cycle.

Safety and Personal Protective Equipment

Always use proper safety equipment, clothing, and PPE in accordance with the Safety Data Sheet for this product, and any surface preparation materials. Only use polyester resin-based products with adequate ventilation.

Surface Preparation

Acceptable Substrates

• Polyester resin*
• Gelcoat surfaces*
• TotalBoat Polyester Structural Repair Putty*
• Cured epoxy surfaces where any amine blush has been removed
• Other fully cured FRP substrates
• Wood substrates

Unacceptable Substrates

• Uncured epoxy substrates
• Epoxy fairing materials
• Plastics
• Glass
• Uncured vinyl ester resins
• Ceramics
• Masonry
• Concrete

* TotalBoat Polyester Structural Repair Putty can be applied directly to any catalyzed, uncured polyester resin-based products. Any cured polyester resin-based products must be dewaxed, all other surface contaminants removed, then sanded before applying Polyester Structural Repair Putty.

General Surface Preparation for All Substrates

• All amine blush, dirt, dust, grease, oil, water, and wax must be removed from the substrate before performing any further surface preparation. Abrading the surface with any of these substances present will only grind the contamination in, leading to a potential adhesion failure.
• Grind or abrade with 36-grit sandpaper.
• Remove all sanding residue with a vacuum and/or an air hose.
• Wipe the surface clean with a clean, lint-free cotton rag dampened with acetone.

Application Over Laminating Polyester Resin, or Other Tacky Catalyzed Polyester Resin-Based Materials

• Polyester Structural Repair Putty can be applied directly to previously catalyzed polyester resin-based substrates such as laminating resin without any other surface preparation.
• For best results, apply within 24 hours of catalyzing the substrate material, after it has cured to a firm but tacky material.
• Finish curing the entire part by one of the specified methods.
• Applying in this method will form a chemical bond with the substrate material.

Application Conditions

• The recommended application conditions for this product are 60–90°F and 0–90% relative humidity.
• Do not apply this product when dew, rain, or other contaminants may be present, as they may affect the cure of this product.

Catalyzation

• Polyester Structural Repair Putty requires MEKP (methyl ethyl ketone peroxide) as a catalyst to cure. This is not to be confused with the solvent MEK (methyl ethyl ketone).
• The ideal percentage of catalyst is 1%, but may vary from 1–2% by weight, based upon ambient temperature and the desired working time.
• For small, quick repairs, the maximum 2% can be added — this provides less working time and a quicker cure.
• For most applications, use the minimal percentage of catalyst to ensure sufficient working time.
• 14 drops of MEKP catalyst per ounce of Polyester Structural Repair Putty provides a working time of 15–20 minutes (at 77°F, 100 g mass).
• Applying less than 1% or more than 2% catalyst may yield undesirable working or cured properties.
• Applying too much catalyst may lead to cracking and a brittle product once cured.
• Under-catalyzation can lead to much longer cure times or insufficient cure with poor sanding/structural properties.
• Immediately mix the catalyst into the putty with a stir stick. Mix thoroughly; uncatalyzed areas will not cure.
• Working time starts once catalyst is added. Mixing can take 2–5 minutes depending on mass.
• Cooling catalyzed putty extends working time; warming shortens it dramatically. Once added, catalyst cannot be removed.

Tinting / Coloring

Though it is not common, Polyester Structural Repair Putty can be tinted with TotalBoat Pigment Dispersions or other polyester resin-safe colorants before it has been catalyzed. To ensure optimal working and cured properties, avoid using more than 1% of any tints by weight or volume. Always perform a test sample with any desired tints before using it on the final project, including catalyzation and sanding.

Application

• Immediately after TotalBoat Polyester Structural Repair Putty has been catalyzed and mixed, spread to the desired substrate with a putty knife, spreader, or trowel.
• Work quickly to maximize working time.
• Once cured, sand with desired grit.
• Polyester Structural Repair Putty cures to a firm, tacky material.

For Air Dry Applications (Curing to a Firm, Tack-Free State)

• When another polyester resin-based product will not be applied directly over this product, paraffin wax can be added at a rate of 1 ounce per quart of putty before catalyzing.
• Other methods include vacuum bagging during cure, or spraying PVA over the exposed surface while curing.
• This is not a finish product — prime, paint, or gelcoat after sanding.
• This material should not be considered waterproof.
• For underwater applications where exposure to water is expected, apply a barrier coat such as TotalBoat TotalProtect over the top as directed to prevent water intrusion, blistering, or other failures.

Storage & Disposal

Storage

Keep container tightly closed. Keep in a cool place under 70°F. Keep container in a well-ventilated place. Keep away from food, drink, and animal food. Keep away from sources of ignition.

Disposal of Empty Bottles

Do not empty remaining contents into drains. Dispose of contents and containers in accordance with local, regional, national, and international regulations.

Shelf Life

• Polyester Structural Repair Putty has a limited shelf life and will, over time, gel in the container without the addition of catalyst.
• Shelf life depends on formulation and storage conditions.
• Uncatalyzed polyester resin shelf life is typically up to 6 months when stored below 70°F in dry, cool conditions.
• Warm product above 60°F before use.

Application Data

Physical Data