Glass Microspheres

5 star rating

Same Day Shipping

For orders placed before 2:30 p.m. ET


  • Item
  • Description
  • Price
  • Qty
  • 22-A
  • 22-A
    1/2 Gallon (4 oz)
  • $17.95
  • 22-B
  • 22-B
    Carton (3 lbs)
  • $89.95
  • 22-C
  • 22-C
    Carton (6 lbs)
  • $159.95


Lightweight, Sandable Filler for Surface Layers

When blended with resin, these hollow glass spheres make a lightweight, sandable filler, perfect for filling in fabric weave, shallow blisters, and the surfaces of core materials. The average bubble is less than 70 microns, about a quarter of a grain of salt. Select this unique size and shape for a variety of reasons:

  • Tiny spheres blend readily for an evenly spreadable paste.
  • They're adaptable to a variety of production processes such as spraying, casting, and molding.
  • Low density reduces weight, lowers costs, and enhances properties for finished parts.
  • Spheres provide lower viscosity and improved flow, and reduce shrinkage and warp.

This filler is compatible with epoxy, polyester, and vinyl ester resin systems. Add filler after adding catalyst to resin.

Mix ratio is 3:1 (filler to resin by volume).


Fillers, when ordered alone, will typically ship in a small or medium box. Where possible, we will combine ordered items to reduce the number of boxes shipped.


Glass Microspheres Glass Microspheres available in two sizes: One 1/2 gallon (#22-A) One carton (#22-B)


5 star rating


Aug 24, 2018  |  By Phil

When using microfiber in my bonding epoxy as a filler, I can use half to two thirds less catalyst and resin while building rods and achieve the same bonding strength since the fibers are mixed into the epoxy and encapsulated by it. Fishing rods don't require much epoxy in construction bonding as a general rule, but often there is a need for more bonding material than expected for a really good bond between the blank and handle. When a miscalculation is made, filling in with microfibers saves a lot of headaches and epoxy, while achieving a very good quality bond.


Oct 22, 2017  |  By Trevor Brasch

Very nice to work with, light weight. fine textured and fairs very well. becomes almost clear when used in epoxy

Product Q&A