I've had to cut down a firebrick so that it will fit the back of my fire. The cut firebrick is in between two other whole ones. What size gap should I leave, if any? At the moment it fits snugly between, but I'm worried about an almighty explosion that might happen if they need to expand!
Any help gratefully received.
Peter Brown : Surprisingly little, There is one correct way to stack the bricks. That is what is called a 'running bond', where the layers of bricks are staggered
so that one rows brick joints are off set from the next layer, layer by layer (Google it )
There are two ways to hold the bricks together, with a traditional clay sand mortar, in which case you are actually holding them apart far enough to deal with slight
irregularities in your bricks -making it easier to level them. Recipes for mortar will depend on the quality of your Clay, but the clay sand cob should be made with
small sized sandgrains of sharp/builders/masons sand the thinner the sand the easier to apply the mortar and the thiner it can be 'buttered on' !
I recommend this method for the Heat Riser when using firebrick ( splits or 1/2 thickness are best )
For the Feed Tube and Burn Tunnel part of the combustion zone you can quickly soak your bricks say 5 seconds in water and then dip them in clay slip, this will
self-tighten up and is in the center of Your monolithic build, and this technique works well in this location.
This was a long-winded way to say yes you can but is a bankable answer ! Big AL
Success has a Thousand Fathers , Failure is an Orphan
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