My wood burning stove needs new firebrick unfortunately the manufacturer is out of business and the firebricks are an odd size ok now the question I was thinking of adding Sodium Silicate (sometimes called water glass) to this batch but have never used it before normal batch would include silica sand, cement, perlite, and fire-clay so should one of the normal components be reduced if adding liquid sodium silicate water solution? your thoughts?
This is quite a specialised field. I'm afraid I have no expertise in it. I see that sodium metasilicate does indeed have applications in refractory ceramics, but that's about it.
Just get some clay ( from the side of road in my case) add 5% more sand, a bit of saw dust, make your brick a little bigger than you need , let it dry, file it down to fit , fire it and that should work. Alex