Mortar Problem

[Jerald P]

I installed my casa 90 modular oven using fire clay and premixed mortar. This seems to be fine for the chimney but the mortar I used on my cooking stone surface is brittle and not holding up well. I am considering regrouting the gaps between the parts of the cooking surface. I think I can use the mortar available and pipe it in with a mortar bag and smooth it with a sponge. Any ideas?

[Alf]

When you say it’s “brittle and not holding up well” do you mean the mortar is disintegrating and coming out of the gaps between floor stones? If so, I wouldn’t bother too much with re-grouting. When installing these ovens I only grout the floor stones to the front of the oven (mainly for looks) and leave the others ungrouted, they eventually fill up with wood ash and allow for expansion within the cooking floor.

Alf

[aikitarik]

Jerald,

I agree with Alf. You don't want to fill in the gaps in the floor because it does a lot of expanding and contracting and you want to be able to easily pull out broken or spalled bricks in the future to replace them.

Tarik

[james]

Hi Gerald,

Other than the mortar, I hope your Casa is cooking up a storm.

We recommend that you fill the joints between the piece shaped pieces, but not between the floor and the dome walls, with refractory mortar -- though it can flake or chip over time. If you want to re-try mortaring it, you can scrape out anything loose, and make sure the cooking floor pieces are really wet, so they don't they pull moisture out of the mortar. You should also let the mortar dry naturally and bring it back up heat slowly.

That said, Alf has a valid point -- which is that is it not necessary to mortar that joint. It will fill up with ash, which settles. If you brush the floor vertical to the joint (not with it), you can easily create a clean floor to cook on. And it won't catch you peel.

I've seen many older commercial pizza ovens in pizzerias with very large gaps in the floor, and many of the older pizza oven in the countryside have stone, not brick, floors -- huge gaps and an ungulating floor. I wouldn't recommend it, but they're fun to see. :-)

James

[Jerald P]

Thanks guys

[nyknicks]

I have the same problem with my oven floor grout. I think I'm going to wait untill the fall and try to re-grout at that time. This time I will really wet my floor tile before I grout. Any suggestions would be more than welcome on this subject.