How to Mix Fireclay Mortar
- 1). Add one part fireclay, one part Portland cement, one part lime and three parts sand into a bucket or wheelbarrow, depending on how much mortar you intend to mix. If you are making refractory mortar, use one part aluminum silicate instead of the Portland cement. When using calcium aluminate, make only small batches because the mortar sets quickly.
- 2). Check the instructions on the Portland cement or calcium aluminate to see how much water you should add to the mix.
- 3). Add about three-fourths of the specified amount of water to the mix, and stir it in thoroughly. Add more of the water while stirring. Stop adding water when the mix is about the consistency of peanut butter. If you are using calcium aluminate, be ready to begin work immediately, because you only have about 15 minutes before the mortar sets.
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