Re: Soaking firebricks

Posted by Rado

In Reply to: Soaking firebricks posted by Eugene

Eugene,
Firebricks love to absorb water as well as they absorb heat. Water based refractory mortar would start to dry pretty fast, as soon as it touches dry brick water is taken out and the mix sets to leather hard. it's so quick that work would become almost impossible especially in a thin mortar applications. As John mentioned this is very easily avoided by simply dipping firebricks in bucket of water, or wheelbarrow for ~1 minute. No need to wet all firebricks, just those that are being mortared in arches. Some commercial premixed refractory mortars can be applied on almost fully dry firebricks even in thin 2mm layer. But there is absolutely not problem with fireclay based mortar, just wet firebrick as mentioned above.

Oven building details Clay-Sand Bed and Refractory Mortars

I also wet top slab surface shortly before placing hearth firebricks onto its surface for the clay-sand bed does not dry in 2 hours (wet the slab well, wait 10 minutes, remove excess water with old cloth and work with the clay-bed spreading it on the slab like peanut butter - if you didn't use the cloth the clay will slip a bit making it a bit harder to spread -- nothing extra special.) r