2024 Neapolitan oven build

[MarkJerling]

I've been away. You've made fantastic progress. Well done!
Oven is looking great! Any pizzas yet?

[daidensacha]

I was very interested in retained heat cooking and knowing the temp of dome makes for some pretty accurate baking. The tip of the probe is ~70mm from the inside surface of the dome.

My dome generally starts to clear around 400-425C. Once I hit that, it doesn't take long to crack 530. No idea how hot it gets bc my IR doesn't read higher.

That makes sense for me, to measure the dome retained heat once the heat has dispersed. I’m interested in making full use of the retained heat, for 4 days following heating it. Meat, bread, cakes. I will consider it once I have rendered the dome. Did you insert a sleeve in which you insert your probe, or just directly install the probe into the dome wall?

530C, is that the temp you target as ideal for baking pizza?

[Giovanni Rossi]

I wanted to integrate a thermometer, but I just can’t decide where to put it, and to measure what? The dome bricks or the internal temp.

My door came with a thermometer that measures the air temp, albeit cooler than what it would be at the other parts of the interior.

I was very interested in retained heat cooking and knowing the temp of dome makes for some pretty accurate baking. The tip of the probe is ~70mm from the inside surface of the dome.

My dome generally starts to clear around 400-425C. Once I hit that, it doesn't take long to crack 530. No idea how hot it gets bc my IR doesn't read higher.

[daidensacha]

That was one of the things that surprised me when I started cooking with full fires. I have a probe in the brick on the opposite side of where I keep the fire. It generally takes 4-6 hours after I stop stoking for my dome to come to equilibrium...shows the difference in conduction properties of brick vs. metals.

My first job was as a pizza cook for 2 years, seems a life time ago, 1982-84. It was a double decker electric oven, and we never really had to change the temp as it was thermostatically controlled. I do remember though when we were busy, opening the oven a lot how the temp changed and sometimes it was really hot. I used to reach right in with my arm and a spatula to move, turn or remove pizzas. It was always in and out to avoid burning my hand as it was hot. 3 seconds was about the max time I could keep my hand in.

I wanted to integrate a thermometer, but I just can’t decide where to put it, and to measure what? The dome bricks or the internal temp. As I’m not clear on that, I decided not to do it, and to go old school, to learn how to feel and read the oven. After 4 days of fires I started to learn already, and it will continue with experience. I’m sure I will make some bad food along the way learning to make good food. Part and parcel of the journey I guess.

[daidensacha]

Reading the dome vs IR Thermometer

I’ve been using an IR thermometer to measure the temperature, which gives me a temp albeit only the surface temp at that spot. I’m watching the dome with interest, and have started to realise I can’t trust the IR thermometer 100%. It gives me different readings depending on where I point it, top hottest, then floor, then the dome from the top center down to the sides gradually decreasing temperatures The top of the dome reads hotter when the flames are touching it, and cooler as soon as the wood burns down.

Russel mentioned a while back that the oven is ready for pizza when the dome is clean of soot. Or that’s what I understood anyway. My fires are getting hotter each day, and I noticed yesterday a spot in the top of the dome above the fire that was clear of soot when the fire is burning clean and hot. Today that spot was bigger, so I put my phone in to take a picture, and was surprised how beautiful it looked. Sharing that image with you below.

Looking at this image, I measured the dome and it was 400C. Hotter again than I wanted but my oven has been drying now for a few months covered and protected. While there is moisture in the dome under the v-p-crete, I’m pretty confident now that the bricks are getting dry. Last night with the door on the oven retaining heat, I noticed this morning that moisture had been venting from the inserted vent in the top of the dome. Seems to happen more when the heat evenly disperses in the dome. I don’t notice any moisture venting when I have the fire going, but it was there in the morning.

I’ll be honest and share I was on edge the first days wondering if the dome was going to crack. 4 days of fires later it has well tested and has held up perfectly so far.

Thanks to FB for the inspiration to build this oven, its so much fun.

[Giovanni Rossi]

That was one of the things that surprised me when I started cooking with full fires. I have a probe in the brick on the opposite side of where I keep the fire. It generally takes 4-6 hours after I stop stoking for my dome to come to equilibrium...shows the difference in conduction properties of brick vs. metals.

[daidensacha]

Notes: Curing fires day 4

This morning first thing I took the flue cap to the manufacturers factory and he had some mesh welded on it. Good that’s done, and he did it gratis.

Yesterday after 7 hours of fire in the oven, I put the insulated stainless steel door right in the oven arch, totally closing it. There were some coals still burning in the pile of ash.

This morning, 17 hours later, I felt the front of the door with interest. It was warm in the middle without being hot, was easy to hold my hand on it. The handles were not warm or hot at all. Around the sides of the door it was around 60C, from the conducted heat. The inside face of the door was 160C. The door held its shape perfectly, without warping.

More interesting was when I measured the inside of the oven. The sides, and at every point of the dome it was the same temp, 200C. It’s like the heat held in the oven evenly dispersed in the bricks, so it was a uniform temp. My fire has been a little more than what I have been aiming for.

Directly above the fire at the top of the dome it is hottest while the wood is burning, with the flames hitting the dome. That temp varies a lot depending on whether the flames are hitting it, or if the wood has burnt down and the flames are low. It’s been up to 360C, down to 300 when I closed the oven, with the sides measuring 170C. As mentioned, that heat dispersed evenly and was 200C after 17 hours with the door on.

In the ash, I was surprised to see glowing coals still, given the door was closed cutting off the air flow.

Each day of fires it takes less fire to heat the oven. Seems that the retained heat is the foundation on which it builds and starts to heat again.

Might just put a chicken in this afternoon when I put the door on, and try david s recipe. Will give me some brownie points with my wife .

This is so much fun.

[daidensacha]

Giovanni Rossi The manufacturer replied and said if I bring the flue cover in he will put a spark arrester around it. Easy peasy. That’s my first job in the morning.

Bonus, we have 3 days of 10-11C, some I’m making the most of it and doing the final coat of render on the chimney. I wasn’t expecting it to be warm enough until next spring. It’s a blessing.

The curing fires are a super introduction to getting to know the oven. Each day it heats faster, and retains more heat. I’ve been putting wood inside at the sides of the dome. When I put them on the coals the ignite real quick. Today there was a 30cm round totally clear spot in the centre of the top of the dome above the coals.

I put the insulated door on this afternoon and closing the opening totally. I want to measure the inner temp tomorrow when I open it to start the next fire. Also curious to see how the door handles the heat.

[Giovanni Rossi]

I used a Duratech flue. They offered a mesh ring arrestor for $30 USD

I could get a small roll of hardware cloth locally for ~ $10 and had a lot left over for other uses. But, I had some remnants form past projects, so cost $0

I know what you mean about "flue anxiety" (could this be a defined FB Forum disorder? ), i used 6' and really didn't want to spend for another section of stainless.

The other mesmerizing view I like is the flame and smoke swirl from a fire at the side of the oven looping along the top of the dome then downward toward the floor and across the top of a pizza !!!

[daidensacha]

daidensacha Been following you since the beginning. Nice work! The payoff is near!!

One thing you may want to consider is a band of hardware cloth under the flue cap as a spark arrestor and to keep out critters.

I was wondering how long before someone noticed that with my flue. 10/10 Giovanni

I’ve been on to the manufacturer to ask them if they can make one up for it. Failing that, I already have a perfect piece of stainless steel sitting in my Amazon shopping cart ready to buy if needed. Just means I need to take it to the engineering shop to put it through the rollers and tack weld it, which I can do, but at this point would happily just buy one that fits from the manufacturer.

I was entranced yesterday watching the mini tornado at the vent opening created from the meeting of the cool inflow and warm outflow of air though the oven arch. Normally invisible to the eye, but with smoke and ash very visible and fascinating to watch. I did stress over whether the flue would work as I wanted it to, and after all the work, it’s outperforming my expectations.

[Giovanni Rossi]

daidensacha Been following you since the beginning. Nice work! The payoff is near!!

One thing you may want to consider is a band of hardware cloth under the flue cap as a spark arrestor and to keep out critters.

[daidensacha]

Congrats, now the food cooking fun starts. Check out Karangi Dude's cooking thread, he goes way beyond cooking pizzas taking WFO cooking to an art.

Hey Thanks Russel. So much to look forward to, and I’m so enjoying getting started on the cooking. Had my second curing fire today, and was thinking of you when I checked the vent I placed on top of the dome. A lot of moisture was coming out which was good to see.

I’ll be starting with pizza, and have a pizza birthday party planned for 23 December. Then on the 24th I want to cook the Xmas goose in the oven. Last year on on the grill rotisserie, but this year in the pizza oven. I will definitely check out Karangi Dude’s cooking thread, thanks for that tip.

[daidensacha]

Castable vent

This was actually the first thing I did when starting on the oven, end of last winter before I could get started on the oven as it was still too cold. david s very kindly shared his knowledge of working with vermicrete to make moulds, and casting with castable refractory.

Photo 1. I had my Schamott flue size, ID Ø200, OD Ø240mm, and from that calculated a vent opening size that equaled the ID of the schamotte flue, 377mm x 126mm. I My goal was to create a mould that would transition from the rectangular vent opening to the circular flue opening with smooth curves so to facilitate unimpeded flow of smoke through the vent and into the flue. The mould was made from 5:1 vermicrete so I could easily remove it from the cast once I had poured the castable refractory. Easy to carve.

Photo 2. I created a form in which I could place and center the mould, and easily remove once the castable refractory was set. I allowed for 50mm thick walls.

Photo 3. The castable refractory set really well, and it was easy to scoop out the vermicerete, leaving the inner of the vent with smooth walls and curves. I bought a schamott adapter plate and made the vent gallery so the adapter plate would nest in the top. It was a perfect fit.

Photo 4. On top of the arch, I then set up some forms to cast a base on which the vent gallery would sit. I used castable refractory again as I had left over from casting the vent. I then used heat proof mortar when placing the vent on the base.

Photo 5. It became a solid base for the flue once the vent was on top of the arch, and the adapter place was mortared to the vent gallery.




No one will ever see it, or fully appreciate the work and planning that went into it, but I will know it is there inside the chimney, and watching the whirlwind of smoke as it flows out of the dome and directly up the vent and flue gives me satisfaction.

[daidensacha]

Stainless steel double walled flue

I thought I would just add some photos of the stainless steel flue.

Actually, it was something I worked out early in the planning process, as I really wanted to to ensure that smoke exited the oven via the vent, and not the front of the arch. Started with working out what size flue, which was 200mm in my case, and then calculating what size vent was sufficient to match the flue. With david s input and guidance, I made a vent gallery out of castable refractory that would sit on top of the arch. (see following post for some images). Then 2 x 300mm x Ø200mm Scahmott flue to sit on the vent. I bricked put around the schamott flue, and then bolted a stainless steel base plate to the chimney, with a single to double walled flue adapter. The 1.5 meter of stainless steel flue then on top though the roof.

Its amazing to watch the flow of air in the oven, created by the cool inflow through the front of the arch, and the warm outflow of smoke filling the dome though the top of the arch and straight up the flue. It creates at times a mini tornado in the vent gallery, which I see from the swirling smoke and ash, which then swishes up the flue. It’s really efficient, with almost no smoke passing the vent opening and coming out the front of the arch.

[UtahBeehiver]

Congrats, now the food cooking fun starts. Check out Karangi Dude's cooking thread, he goes way beyond cooking pizzas taking WFO cooking to an art.