40" WFO in the New Orleans

[sharptailhunter]

Re: 40" WFO in the New Orleans

Nice progress! I like the cantelever design of your heart. What are you using to fill the center void?

[banhxeo76]

Re: 40" WFO in the New Orleans

Nice progress! I like the cantelever design of your heart. What are you using to fill the center void?

The center void (only 4.5" deep) will be filled with 2" of insulation ceramic board, 5" of firebrick (two layers of 2.5" firebricks). However, the first layer of firebrick will flush to the same height of concrete countertop which I will place one layer of fire brick on part of the concrete countertop for the vent landing area to even thing out. There is no insulation under the firebrick in the landing vent area. I know that I am going against the grain with most people who have built their ovens on this forum. I just don't see the need for insulation under the firebrick around landing vent area because I believe the heat supposed to rise up through the brick in this area and then through the vent (if heat even transfers that far).

Only time will tell if I make the right decision.

[banhxeo76]

Re: 40" WFO in the New Orleans

Okay, I think I pretty done with the main design for my WFO. I will be building a hybrid dome, meaning that my dome will not be too high or low. At first, I was planning to do a flare out openning vent. After I laid some bricks to do some mock up, I decided to just go straight vent opening because I believe straight out vent provides more solid structure than a flare landing vent.

Of course, my diameter will be 40".
Dome height will be 17.5" high (close to 63% ratio to door height)
Inner Arch opening will be 11" high & 19 " wide
Landing Vent will be 23" x 13.5"
Outter Arch will be 12.75 high x 23" wide

I am thinking about extending the fire brick layout all the way to the edge of the counter top. My other option is to increase the countertop by using the premix concrete countertop w/ color and leveled it with the fire brick which stop at the landing vent floor. However, I can decide on this a few months from now.

[banhxeo76]

Re: 40" WFO in the New Orleans

As soon as the weather gets better on the weekend, it is time to mortar them bricks together. I am going with homebrew rather than premixed refractory mortar due to cost. I was vacationing in DFW area during Christmas and saw a few posts by Lburou in regard to ciment fondu (which is a Cal. Alum. Cement) and he used the ciment foudu for his homebrew. I brought a bag of ciment fondu (90lb for $75) and a bag of fire clay (100lb for $25) from Wesco Refractory (those guys at Wesco were great) and drove home to New Orleans. No masonry vendors in New Orleans area sell fire clay anymore because nobody makes their own homebrew for fireplace anymore. Everybody is selling the wet mix which is a big "NO, NO" for outdoor WFO. I brought some fine sand from local hardware store and I have to say that Quikrete?s fine sand is very similar to the Quikrete?s play sand, if not the exact same thing. I went ahead mixed some homebrew and did some test on the scrap bricks to test it out. Dried brick really absorb the moisture out of the mortar very fast and make it impossible to work with. Then I used soak the bricks (for a good 15 minutes) before mortar them and it seems to be more workable. Peanut butter like consistency is an idea mix but it seems to be very hard to work with even with a wet bricks. Running toothpaste like consistency is more workable but the strength of the mortar won't be as strong as the peanut butter consistency. I guess I will have to follow DinoPizza?s suggestion by using the running toothpaste consistency for the inside and fill in later with the peanut butter like consistency on the outside.

This WFO project is soooo much fun. I just love it.

[banhxeo76]

Re: 40" WFO in the New Orleans

Little bit more progress over the weekend. The mock up inner arch looks better than I had anticipated. I just hope that mortar up inner arch will look just as good as the mock up after I have done mortar them together. Hopefully, I can mortar some time brick this week.

I have to clean up all the tapered bricks before I can mortar them. If I don't clean them brick, the mortar won't stick on the brick as well as it should because the dust on the brick will act as released agent which is a bad thing. I hate cleaning but it is necessary.

[PizzaIdiot]

Re: 40" WFO in the New Orleans

For your arch, do you just 'squirt' the mortar in with a mortar bag or use a small tool and work it in? How wet is your mortar?
Thanks,
Jeff

[Amac]

Re: 40" WFO in the New Orleans

Hi banhxeo76
Some beautiful brick cuts. I'm very impressed with your progress. In contrast I seem to take forever - but I'm enjoying the process. Is that really a double floor of firebrick? Do you think it will be harder to heat with so much brick? I have 3" brick but most here seem to have 2.5".
Well done so far - looking forward to seeing it all come together. I agree with you btw - it is the bread I am looking forward to more than the pizza.
Amac

[banhxeo76]

Re: 40" WFO in the New Orleans

For your arch, do you just 'squirt' the mortar in with a mortar bag or use a small tool and work it in? How wet is your mortar?
Thanks,
Jeff

My mortar is between a consistency of peanut butter and wet toothpaste. I just apply the mortar on the lower side of the brick. Then I laid down the buttered up brick and lightly push the brick to make sure you get a good contact of mortar on the other brick. You just work your way up until you get to where the keystone would be without mortaring in the keystone in yet. Then, you start working from the opposite end and work your way up. On the last brick which is the keystone brick, you should place it in position without mortar just to see how much mortar you need on each side. You may need to cut the keystone if necessary if it is too tight. Then you would buttered up both side of the keystone with mortar and push it into position. You should lightly tap on the brick with rubber or wooden mallet if necessary. Some mortar should ooze out a little bit. Ooze out is a good thing to ensure that mortar joint has contact on both brick. I only use the putty knife to apply more mortar into the joint if necessary.

Make sure that you soak your brick in water for 15 minutes before you mortared up them because the dry brick may suck the moisture of the mortar before you can do anything. However, let the wet soak brick air dry for about 5 minutes before you buttered them up with mortar because super wet brick may not absorb the mortar as well. Also you may have to adapt the procedures base on the climate of your area. Just play mortar and brick a little bit and you will eventually figure out what work best. I am still learning about mortar.

[banhxeo76]

Re: 40" WFO in the New Orleans

Hi banhxeo76
Some beautiful brick cuts. I'm very impressed with your progress. In contrast I seem to take forever - but I'm enjoying the process. Is that really a double floor of firebrick? Do you think it will be harder to heat with so much brick? I have 3" brick but most here seem to have 2.5".
Well done so far - looking forward to seeing it all come together. I agree with you btw - it is the bread I am looking forward to more than the pizza.
Amac

Amac,

Thanks for the compliments. It is indeed double bricks. I will have 5" of hearth floor for BREAD and pizza! It will certainly take more wood to heat up my WFO but this is what I want and intend to do. It is very important to have thick mass on the hearth floor for hearth bread. Once you drop the thick dough on the hearth floor for baking, the surface will cool down quickly (unlike a thin dough for pizza). However, thicker hearth floor will recover and recharge the cooking surface quicker because of thicker mass on the bottom. Hearth floor is supposed to be thicker than the wall and the dome for bread purpose. Keep in mind that the hearth floor is the only place in the WFO that is having any contact with food source. It just makes sense to add more mass to the hearth floor. Alan Scott’s design which is a barrel vault, has at least 8” of hearth floor thickness (4.5” brick & 3.5” Concrete”) which is designed more multi cooking. At the end of the day, I will use more wood but it is hard to say if my bread will taste any better unless I build an exact WFO with a standard 2.5” hearth floor but my wife will KILL me.

[Neil2]

Re: 40" WFO in the New Orleans

Is the "center void" drained ?

You may want to look at doing this even if it means drilling some holes through your suspended slab.

No oven is truly waterproof and if you do get water in this void you will have a very frustrating effort getting it out.

[banhxeo76]

Re: 40" WFO in the New Orleans

Is the "center void" drained ?

You may want to look at doing this even if it means drilling some holes through your suspended slab.

No oven is truly waterproof and if you do get water in this void you will have a very frustrating effort getting it out.

I do have holes on all four sides of the void. I am planning to build an enclosure over my WFO. Other than the moisture from the humidity, I don?t think much water will be sitting in the void for long because the concrete slab itself will absorb the water if any gets to the void. But like I mention early, I did have some holes for drainage for just in case. Thanks for noticing the potential problem.

[Neil2]

Re: 40" WFO in the New Orleans

A lot of the initial and seasonal curing problems discussed on this site are related to poorly drained and ventilated insulation layers. "just in case" extra drainage holes are a good idea.

[banhxeo76]

Re: 40" WFO in the New Orleans

Gasoline cost roundtrip to Box Store $2.50
4 sets of nuts and bolts $1.96
Door Stop $4.21
Red Oak 2x2x36" $9.42
A peace mind for an idiot like myself on how to build prefect round WFO...Priceless!

Indispensible Tool, don't ever build WFO without it.

Thanks to jcg31 & kibwi for the ideas!

[banhxeo76]

Re: 40" WFO in the New Orleans

I just finished course number 5. I wish I had taken more pictures to document my WFO project. However, it is hard to stop working just to take picture once you got going. Mortaring is an learning process. Wasted a lot of mortar in the first 4 courses but course 5 was a breeze. I am aiming to get course 6 and 7 done this weekend.

The most nervous part so far was the inner arch. But it was not that bad at all because the form was a great guide. I will work on the outter arch/vent when I am done with the dome.

This project is so much fun!!

[banhxeo76]

Re: 40" WFO in the New Orleans

5th Course