Glass Bubbles are hollow glass spheres with a more variable particle size than microballoons.
Being composed chemically of glass, they are physically harder than microballoons and filled resin mixes are noticeably more difficult to sand. However, glass bubbles produce a more waterproof filler mix.
Being significantly less expensive than microballoons they are often preferred if ultimate sanding performance and colour are not of prime importance.
They can be mixed with microballoons in any proportion for colour purposes.
Composition: 'C' Glass.
Appearance: White Powder, free flowing.
Particle Size: 40-80 microns.
Bulk Density: 100-150g/litre