Sika BPO Cream Hardener for Polyester Fillers

Description

Sika BPO cream hardener is the benzoyl peroxide catalyst that cures Sika’s amine-accelerated polyester filling and fairing compounds, including SikaBiresin AP077 and the wider APF and Micro-Ultra filler lines. The cream format meters easily against a measured scoop of resin paste, which helps crews hit a consistent mix ratio batch after batch.

How BPO Cream Hardener Cures Polyester Fillers

Sika’s published mix ratio runs 100 parts resin paste to 2 parts BPO cream hardener by weight, described as a golf-ball-size scoop of filler paste against roughly a two inch ribbon of hardener from the tube. Once combined, the paste sets in 5 to 10 minutes at room temperature, so mix small batches and work quickly once the hardener is folded in.

Cure speed and final hardness track ambient temperature and the amount of hardener used. Adding more than the specified ratio does not reliably speed cure and can affect finished strength and sanding behavior, so measure rather than estimate by eye once a crew is dialed in on the right proportions for the shop’s typical conditions.

BPO Cream Hardener Packaging and Color Coding

This hardener ships in 1 ounce and 4 ounce tubes in black, white, and red, letting a shop color-match the hardener tint to the resin paste being cured or to keep hardener batches visually distinct on a busy bench. Confirm the tube color and size against the resin system in use, since different Sika filler lines are validated with specific hardener grades.

Product Specifications

Browse Chemical Concepts specialty repair adhesives for compatible resin pastes. For the current technical data sheet, visit Sika.

Need Help?

Need help matching hardener color and tube size to your resin paste? Call (800) 220-1966 or email [email protected].