Acrylic Resin Filler - Marble Powder

Marble is a form of calcium carbonate. When mechanically ground into a fine powder it produces a versatile filler that can be used in many applications including resins and paints. 

In non-strength critical Acrylic Resin Castings, this powder can be added at levels up to 200% of the resin weight. It will reduce the flow of the resin signification and you can easily reach a point where the resin will not flow freely and will not self-level. As an example, 100g of resin can have up to 200g of Marble Powder added into it. This is the highest recommended level based on strength and will be too high for certain applications. The terms "Filler" and "Extender" basically mean the same thing and refer to materials that are added to reduce the cost of the casting. 

After adding the resin powder into the resin liquid (done with stirring) then simply add the Acrylic Resin Filler - Marble Powder in while mixing. You will notice the thickening effect. 

Do not add the Marble Powder to castings where strength is critical.

If you are making a fairly deep casting then the cost can get very high. One way to reduce the cost is to make a Gellcoat (Acrylic Resin plus Thixotropic Thickener that will not flow freely). Brush this into the mould in a layer of at least 2mm thickness. This layer will not have Marble Powder and will give outer strength. When this layer has cured into a paste consistency then fill the rest of the mould with Acrylic Resin that has been mixed with this Marble Powder.