LOCTITE EA 3478 Metal Repair Epoxy is a two-component, ferro-silicon-filled epoxy system developed for rebuilding and restoring worn or corroded metal components. It cures at room temperature after mixing and creates a hard, metal-like gray finish that can be machined. This high-strength repair compound helps restore component dimensions without welding, reducing downtime.

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Key Benefits of LOCTITE EA 3478 Metal Repair Epoxy

LOCTITE EA 3478 Metal Repair Epoxy combines high compressive strength with resistance to corrosion, abrasion, and chemicals. Its paste consistency allows technicians to rebuild damaged areas, fill surface defects, and create stable repair profiles without excessive flowing. Once cured, the repaired section can be drilled, tapped, filed, ground, or machined to achieve the required tolerance.

The two-part system is supplied as resin and hardener. The recommended mix ratio is 4:1 by volume or 7.25:1 by weight. At room temperature, the mixed product offers approximately 20 minutes of working life, giving technicians time to apply, shape, and compact the material on prepared metal surfaces. Its 100% solids formulation helps build substantial repair thickness without solvent shrinkage.

Applications for LOCTITE EA 3478 Metal Repair Epoxy

This industrial epoxy is ideal for restoring worn shafts, repairing damaged keyways, rebuilding bearing housings, filling pitted machinery surfaces, and recovering corroded equipment. It can also be used on pump housings, gearboxes, machine beds, flanges, castings, valve bodies, and other metal parts affected by wear or corrosion.

LOCTITE EA 3478 Metal Repair Epoxy is useful where replacement parts are costly, difficult to source, or likely to cause extended shutdowns. By rebuilding the existing component and machining the repair back to its original dimensions, users can extend equipment life and return machinery to operation faster. The product is intended for industrial maintenance and surface repair rather than flexible bonding or moving joints.

LOCTITE EA 3478 Metal Repair Epoxy Technical Performance

The mixed material has a typical specific gravity of approximately 2.13 and develops a hard cured surface with a Shore D hardness of about 86. Henkel reports typical tensile strength of 27 N/mm² and lap shear strength of 19.5 N/mm² on grit-blasted mild steel under specified conditions. A typical compressive strength of 134 N/mm² at 65°C supports highly loaded metal restoration work.

These values are reference data rather than guaranteed purchase specifications. Actual performance depends on substrate condition, surface profile, mixing accuracy, application thickness, curing temperature, and service environment. Users should complete trials before approving the product for critical repairs.

How to Apply LOCTITE EA 3478 Metal Repair Epoxy

Remove oil, grease, rust, loose material, and contamination before application. For maximum long-term performance, abrasive-blast the repair area to clean metal with sharp-edged grit and create a surface profile of approximately 75 to 100 microns. Clean the blasted surface and apply the epoxy before oxidation or contamination occurs.

Mix the resin and hardener thoroughly until the color is uniform. Apply the material firmly to the prepared surface, pressing it into the profile to reduce trapped air and voids. Build slightly above the final dimension to allow machining after cure. Square repair edges provide better support than thin feathered edges. Apply within the recommended temperature range of 15°C to 30°C and clean tools immediately with a solvent-based cleaner.

Why Buy LOCTITE EA 3478 Metal Repair Epoxy?

LOCTITE EA 3478 Metal Repair Epoxy offers a cost-effective alternative to welding, part replacement, and prolonged shutdowns. Its machinable metal-like finish, high compressive strength, and resistance to wear, corrosion, and chemicals make it a reliable choice for industrial maintenance teams. Review the official Henkel technical data sheet before use, and explore our industrial metal repair compounds for additional rebuilding and maintenance solutions.

industrial metal repair compounds