SprayCore Blue Hardener, Cream Catalyst for Polyester Body Fillers

Description

The SprayCore Blue Hardener is a quick-setting, non-separating cream catalyst formulated to use with polyester body fillers, specialty fillers, and finishing putties. The blue tint helps you confirm a consistent, fully mixed batch before troweling, so you avoid soft spots and under-catalyzed cure on the work surface.

What the SprayCore Blue Hardener does

The hardener is a benzoyl peroxide (BPO) cream catalyst, the standard initiator for unsaturated polyester body fillers. When mixed at the recommended ratio with a polyester filler, the reaction generates exothermic heat and builds a sandable surface in minutes at room temperature. The non-separating carrier keeps the BPO in suspension so the working ratio stays consistent through the life of the tube.

How to use the SprayCore Blue Hardener

Squeeze a ribbon of hardener onto the body filler at roughly 2 percent by weight (follow the filler manufacturer’s specific ratio). Mix on a clean board with a flexible spreader until the color is uniform and there are no streaks. Trowel the mixed filler onto the prepared surface within the stated pot life, typically 3 to 5 minutes. Knock the filler down with coarse grit once it firms up, then finish-sand.

Handling and storage

Wear gloves and eye protection. Store the tube tightly capped in a cool, dry place away from heat and direct sunlight. BPO is an organic peroxide and degrades faster at high temperatures, so warehouse inventory below 80 degrees Fahrenheit when possible to protect shelf life. Avoid contact with strong reducing agents or accelerators that can trigger an uncontrolled exotherm in the tube. Dispose of cured, set-up filler in line with your facility’s hazardous waste protocols and local regulations.

Stocking polyester fillers, applicators, or a sanding system to match? Our team can size a kit for your shop’s volume and turnaround needs. Call (800) 220-1966 or email [email protected]. Compare options in our specialty chemicals category, or visit ITW Performance Polymers for SprayCore technical data.