1st Major Mistake

[mk e]

The form is 56" in diameter.

38 " oven floor
4.5" half brick x 2 = 9
4.5" insulation x 2 sides = 9

So, even if it sticks out a few inches, that's just the insulation layer. The brick are still several inches in farther.

Another option is just switch to 2" ceramic blanket insulation...that should put you right where you need to be size wise to fit looking at the pics..maybe even 3" and at 3" you could stick with the perlite and be ok but 3" ceramic would be very good. I think its easy to get wrapped up in "the plan" but a little flexibility (aka spending ) should get you back on track mostly to plan.

or as you say add to the back, you could bolt a 4" angle to the back and come up with 4" block, then drill in at a 30-45 angle and drive in rebar pins so it can't ever separate.

either way, what you have so far looks great.

[mongota]

I agree with what has already been written.

I've been using my 42" oven for a couple of years, my landing is 1-1/2 bricks deep. Adding another brick to make that 2-1/2 bricks deep might restrict lateral/vertical tool movement within the oven, to include doming a pizza should the need arise.

Also, confirm the positional relationship between your dome ring form and the plywood arch form. If that ring includes brick and insulation thicknesses, You might find that a portion of the arch form should 'sit inside' the circumference of the ring form. The two forms would 'overlap' instead of simply touching tangentially.

[Chach]

Guess I'm confused is it just overhanging the back because if thats the case then yes your landing could be smaller to bring the oven back on the hearth I also did 1 1/2" bricks as the landing would be only 13 1/2" instead of your 2.5 bricks which is 22 1/2" so that would save you 9" front to back. If the sides are fine then this probably would make it work for you.

[UtahBeehiver]

I am going to assume that the bender board form that is 56" diameter is the outside of the oven which includes the insulation and final outer coating. In the pic showing the form, the actual form sits quite a ways in from the outer edge. The bottom of the inside of the inner arch form sit on and intersects the ID of the dome. I have attached a pic to give you an idea of how far in the inside of the inner arch sits. The vent chamber depth can be be as little as ID of the chimney. Being a 38" you are right on the edge between 6" and 8" vents. My finished oven goes right to the edge of my hearth but does not hang over. Step back and re-establish the placement of the arch, depth of the vent chamber and final outer decorative arch. You can fiddle with the depth. I think mine projects about 12" from the front of the inner arch to the front of the decorative arch. You can push the decorative arch right to the edge of the diagonal part of the hearth.

[JRPizza]

2.5 bricks seems a little deep. I made mine 1.5 bricks based on forum input. Recommend doing a forum search on vent depth/length. Too deep and it makes it difficult to work food around the oven. If you want to put a decorative arch in front of the forward vent arch you can add some more thickness.

[Chach]

Chris,

First Breathe..........now I would keep all these concerns in your build thread so it's documented with your progress. You can always pour 4" of concrete all around the perimeter. Just drill some rebar dowels in your existing hearth slab and then rebar across them frame it up and you should be fine. You can extend the hearth a little more especially since it is more for esthetics rather than to hold up anything and you should be good to go. I know it stinks that a minor issue will set you back a little but really you got this it's more of an inconvenience than anything at this point. We all had our own share of similar things to this we prevailed and you will too. Make sure you provide enough room for your landing and outer arch as well. Now go get em.

Ricky

[Chris inPA]

How long is the normal entry arch. I was planning on 2.5 bricks in depth. Dropping that to 18" would yield a little.

[Chris inPA]

To make the opening parallel to the diagonal edge of the table puts the form over the edge.

When I angle it slightly, it looks stupid.

[Neil.B]

I'm a bit confused. If your form is 56" and includes the floor, dome bricks and insulation, then why would it overlap the hearth edges as you have included everything within your form? Your pictures show the form up to the edge.

[Kvanbael]

Just make the oven a bit smaller. Then it will all look intentional. All other options will be visual compromises. What inner diameter were you going for? How much would you loose?

[Chris inPA]

The form is 56" in diameter.

38 " oven floor
4.5" half brick x 2 = 9
4.5" insulation x 2 sides = 9

So, even if it sticks out a few inches, that's just the insulation layer. The brick are still several inches in farther.

[Neil.B]

I thought I had built a hearth for a 36", in the end I had to change to a 32" to allow for the insulation blocks. My build is against two fences so I had no choice.

I'm new to this so not 100% sure.

Don't forget you inner arch is set back and not on the edge of the circle, so that will save 4"-6" for the landing.

Maybe drill holes around the edges and insert steel rods, then concrete. I'm not sure what you would glue the rods with, maybe two part glue.
If your main hearth has the dome bricks up to the edges then the extended won't need to take a lot of weight for the insulation.

[Chris inPA]

Here's a few pictures. Looking for suggestions

[Chris inPA]

Well, I made a significant error. My hearth design isn't wide enough for my original design. When I poured all I need to do was make it a few inches wider. Simple math error that I really should have caught before the pour. I don't have a lot of yard space to begin with. So, I was trying to make a corner build in a small rectangular area.

Now I can't angle my oven into the corner like I wanted to. If I did, the form will be off the edge of the hearth table itself. I'm looking for ideas on how to salvage this.

Ideas that I have so far:
1. Angle it straight on to the rectangle shape of the table.
2. Make it smaller than planned (my least favorite option).
3. "Hang" the edge of the insulation layer slightly over the edge of the hearth. My 2nd least favorite solution. If I wind up doing this I'll likely pour a column for support.
4. have the opening to the oven at an askew angle to the edge of the hearth. This will likely look appalling.