3M Glass Bubbles Filler Powder

3M Glass Bubbles

Glass bubbles are hollow glass microspheres mixed into resin to create a lightweight, easy to sand fill compound. Use them for stringer fills, ding repairs, fin box fills, and foam sealing coats on foam blanks.

Compatible with polyester and epoxy resins.

Mix ratio: roughly 3 to 5 parts bubbles to 1 part resin by volume, until the consistency holds shape rather than running. Mix resin and hardener fully first, then fold in bubbles by hand — power mixing crushes the bubbles and reduces weight savings. Let the fill cure completely before sanding.

Color : White

Available in 32 oz. and 2.5 qt buckets