All surfaces must be clean, dry, sound and free of dust, oil or contamination. Clean metals with mineral turps or white spirits and wipe clean. Adhesion to metals can be further improved by light sanding.
Application: Using a spatula, remove the required amount of H.B. Fuller Building Filler™ resin from the can and replace the lid tightly. Use a flat board or the inside of the lid as a mixing tray. Add one pea size of Building Filler™ Hardener to one golf ball size of Building Filler™ resin (1 part hardener to 50 parts filler).
Mix together using a spatula until the colour is even. Ensure sufficient mixing to until a uniform colour is achieved. Apply to the crack or hole using a spatula and work out any air pockets. Tool to the desired shape, slightly over-filling to allow for sanding. Once the surface is tack-free (20 - 30minutes) the surface can be leveled with a fine plane or file. When more fully cured, after 30 minutes, the surface can be sanded. If the sandpaper clogs, allow a few extra minutes for the filler to cure further before resuming sanding.
Curing: Working time is short as 3 minutes in summer and up to 8 minutes in winter. For faster cure, add slightly more hardener. For longer working time, add slightly less hardener. Building Filler™ cures in about 30 minutes to a state that can be sanded and fully cured with in a few hours.