I have a quick question for the pro's.
I was just talking to someone about the placement of the burner for the furnace.
He tells me that living in Toronto that the burner has to be in the clockwise position because of being in the northern hemisphere. Is there any validity to this claim? Thanks in advance guys
You could use fireclay / sand but it will be heavy, I'd still go with the blanket because the castable mix takes more fuel to heat up the refractory where the blanket is basically instant, also the castable will be hot for a very long time compared to the blanket.
Plaster of paris and sand in 2parts plaster 1 part sand works but takes a very long time to cure and will fall apart. Good only if blanket is not available and will degrade over time best if left undisturbed ie; stationary forge vs mobile
I used “sodium silicate” (aka furnace cement) mixed with perlite in my first furnace. It lasted 10 years of moderate use before it rusted out. It wasn’t cheap but it was obtainable. I’ve also heard of pure sodium silicate being used as a rigidizer for the blanket insulation.
I tried to purchase some ciment fondu from lafarge to make my own castable but they only sell it by the pallet.
I went with the perlite and sodium silicate because it was a very inexpensive option. Sodium silicate can be made from silica crystals (cat litter) and sodium hydroxide (drain cleaner). Perlite is cheap from the garden store. PPE required for sodium hydroxide!
As stated, it holds up very well with the added advantage of being super light and movable. It does not get hot on the outside either so I imagine it's very energy efficient.