Refractory Base - Mortar?

[evro50]

Hi All,

Got a quick question regarding mortaring joints between precast refractory panels...

The kit I have comes as 4 pieces for the base and 4 pieces for the dome. Instructions call for assembly then give a 30mm coat of cement around the outside perimeter of the dome.... but they also don't have any fibre board insulation underneath the base which I've added thanks to these forums..

Basically there are a few largeish gaps inside the oven, specifically around the perimeter of the base where you can see the ceramic board underneath. Should I mortar around with high temp mortar (have some wet mix vesilux 3000 available)? I'm basically concerned about any nasty chemicals that might come from the ceramic board (nice and itchy after cutting it so it has me worried about what it will do to the food thats cooking inside!).

Or am I basically trying to solve a problem by mortaring with another chemical thats probably just as bad as the board?

Silly question I know, but better to ask!

[dakzaag]

Re: Refractory Base - Mortar?

I'm not sure if those panels have to flex a bit when they cycle through the temperature range. I would think the manufacture would be able to give some guidance regarding the various openings.

[evro50]

Re: Refractory Base - Mortar?

Honestly manufacturer was not very helpful, their diy instructions fly against most of what I've read on these forums. Had I joined here prior to purchasing would not have picked this supplier thats for sure.

I'll try mortaring not comfortable cooking over visible fibre board, worst case it will be the weak point and crack under any heat stress..... I hope!

[Gulf]

Re: Refractory Base - Mortar?

Hi All,


Basically there are a few largeish gaps inside the oven, specifically around the perimeter of the base where you can see the ceramic board underneath. Should I mortar around with high temp mortar (have some wet mix vesilux 3000 available)? I'm basically concerned about any nasty chemicals that might come from the ceramic board (nice and itchy after cutting it so it has me worried about what it will do to the food thats cooking inside!).

Or am I basically trying to solve a problem by mortaring with another chemical thats probably just as bad as the board?

Many of us have purposefully left a gap between the oven floor and the dome walls for floor expansion. Mine is roughly 1/4". (That is 6.35 mm, if my conversion chart is correct.) That was left to fill in with ash.

If I were to fill in a large gap with mortar (30 mm sounds like a hll of a gap), I would place a band of corrugated cardboard against the base of the dome walls. It can then be left to later burn out and fill in with ash. I think that I would also leave some expansion joints in the grout about every 8? to 1? around the perimeter of the floor. Again, I would use the cardboard at each joint. That would break that long ring of grout into smaller sections.

Maybe some one with some knowledge of your premixed mortar can help you with that question. I would probably go with home brew.

Some pics would help .