K79 Oven Build

[K79]

Re: K79 Oven Build

Yes, many kilns are built with no mortar, but I think you should mortar the entry bricks well.

What do you mean by mortar them "well". 1/4" joints?

[mrchipster]

Re: K79 Oven Build

No gaps on the hot side if possible. But some mortar to reduce the chance of. future dislodging by an oven tool.is what I think was being referenced here.

Chip

[K79]

Re: K79 Oven Build

Ok so I went home on my lunch break and cut 2 bricks which made 4. I just placed them, I'll square them off when I mortar them, but how do they look. There are going to be some mortar joints here and there on the inside of my dome. Is 1/8" to wide?

There's no issue with placing the cut face of the brick on the inside of my dome is there?

Also these are just off to the right of my entry (it's where I placed the first bricks I cut months ago so you won't see them... my cuts weren't so good back then... not that they're great now )

[Les]

Re: K79 Oven Build

I don't think 1/8 is too large of a gap. The thinking is (was) that it would accelerate spalling. I haven't seen any evidence of that in my oven but I don't use it 24/7 either. If you are not going to mortar every brick make sure that they are tapered so they don't "drift" out. The cut face is fine if it is on the inside, just about every on of mine are that way because it was a cleaner look.

[K79]

Re: K79 Oven Build

All the bricks fit pretty tight. Should I coat the entire outside of my dome with a little mortar when I'm done? Maybe mix in some vermiculite while I'm at it. I really can only add about a 1/2" to my dome when complete so my framing fits. Basically the issue would be me hitting the brick with a pizza peel or roasting pan right?

[Les]

Re: K79 Oven Build

If you hit a brick with your peel I don't think it is going anywhere because there is a lot of weight on it.

You do have plans for insulation, correct? You are going to need a lot more than 1/2 inch.

[K79]

Re: K79 Oven Build

3" fiber blanket and I'm going to burry it in vermiculite. I was wondering how the brick would would drift out?

[Les]

Re: K79 Oven Build

I was wondering how the brick would would drift out?

Maybe I should have said drift in. These things expand and contract with the heat cycle. If you don't use mortar the only thing to keep it from moving (in) is the taper.

[K79]

Re: K79 Oven Build

Maybe I should have said drift in. These things expand and contract with the heat cycle. If you don't use mortar the only thing to keep it from moving (in) is the taper.

Ok got ya. All of my bricks are tapered so I guess I can omit the 1/2" of mortar around the outside of the dome.

Thanks

[K79]

Re: K79 Oven Build

Are these dimensions ok for my keystone for my inner arch? Kind of small I think...

[K79]

Re: K79 Oven Build

Do my vent arch bricks need to be taperd or is the above design ok?

[UtahBeehiver]

Re: K79 Oven Build

K79,

IMHO, I would try and avoid the narrow "chip" key. Based on what I am seeing on your build you have access to a saw and skill that allows you to taper your bricks and that is the direction I would go but an option would be to use a mortar joint on the bottom portion of the arch across the entire arch, roughly an 1/8", to make up the gap in the middle. But again the inner arch is not as visible as the outer arch.

[K79]

Re: K79 Oven Build

Ok, thanks for smacking some sense back into me UtahBeehiver. Below is the new design. My keystone is not tapered here, only way to make it fit, but there are mortar joints on each side at the top that make it 1/4" larger than the bottom. Also at Location "A" marked below is this connection ok? I notice some people make a lip on their vent wall bricks to rest the first brick on and some don't. I don't see the need for it here .... right?

[UtahBeehiver]

Re: K79 Oven Build

I did a full arch so this is above my pay grade so others will have to respond to the Location A question. While you are at it you may need to consider some type of buttressing of your vertical wall, again I did not do this type of arch but the opionions of those who did seem to lean towards some type of buttressing.

[Les]

Re: K79 Oven Build

K79,

Your arch location "A" will not be a problem. I would be concerned about no taper on the keystone. We have seen one that slid out.

Russell is correct about supporting the vertical wall, it's the safe thing to do.