My 32" oven build has begun

[OscarA]

Hi everyone firstly I'ld like to thank everyone for their input into this forum as it's not only has been a big help but without it I probably wouldn't have even attempted to build an oven.
I have a build thread in the Australian regional section but this is a more appropriate section.
My oven will be a 32" pompeii oven and at this stage I will be making it 19" tall to enable a larger entry.
I'm at the stand stage (just poured the top slab yesterday).
Here are some pics feel free to give me advise or tips especially about the taller dome than standard.

[OscarA]

Re: My 32" oven build has begun

More pics.

[OscarA]

Re: My 32" oven build has begun

I now have two weeks before the actual oven itself begins so now is the time to really finalise my plans.
I am going to build a 32" mainly because I can't envisage needing a bigger oven and I don't want long heat up times as that will only reduce the amount of use the oven gets. By building it slightly taller than standard It's probably equivalent to a 34-35" oven in total area ( just an estimate no maths used to work it out ). I'm hoping for a heat up time of around 90mins does that seem about right for this size oven?.

[eprante]

Re: My 32" oven build has begun

Oscar,
My 42" oven heats up in 90 minutes. The key is insulating it well. With a smaller oven syou are going to need firewood in smaller pieces I would think. I already have my firewood double split. I would read the wrong dimensions thread before changing any height/diameter ratios.
Good Luck,

Eric

[OscarA]

Re: My 32" oven build has begun

Hi Eric thanks for your reply.
As you say insulation is key so that's one area I will pay attention to.
I have read a few post where some people have made taller domes than standard with great results. That thread you mentioned is extreme alterations and I feel for the owner as that's not what he wanted from the builder.
I might even go the extra few inches and make mine 36" and keep the dome height to 18". I'm not sure on the maths but making a smaller oven with a higher dome might not make sense as a slighlty larger diameter with similar height could be similar size in total area. Can someone with maths skills work out total area of a 32" oven with a 19" dome height compared to a 36" oven with a 18" dome height.
My head hurts

[eprante]

Re: My 32" oven build has begun

Oscar,
people have been making these ovens for a very long time. The Pompeii design is well tested and proven. There are plenty of areas for individual interpretation when it comes to the enclosure, decorative aspects and entryway. With the use of the Indispensible tool or other arch form tool you are going to get a clean geometric design. If you really want to deviate from the Pompeii plans, then go the Neopolitan design route,which calls for a lower but not higher dome height. You already have enough work invested in the project that you want to use a proven design. Most people on the forum that have taken a markedly different approach than the plans( or somebody else's plans) end up asking questions on the forum about how to improve their ovens performance and correct their flaws. You don't cook anything in the top of your oven, having it higher than the plans call for seems like a good way to lose efficiency. You want the heat reflected down to the hearth. I have only built one oven so I am not an expert, but my oven followed the Pompeii plans and it works well( the limiting factor being the skill of the oven operator). I baked 7 loaves of bread yesterday. My best bread yet I am proud to announce.

Read, study the archives, and ask what you hope to gain by your design change. I can tell you that I haven't seen the dome of my oven since I finished it.

Good luck and if you do come upon a new design let us know how it works.

Eric

[dmun]

Re: My 32" oven build has begun

I might even go the extra few inches and make mine 36" and keep the dome height to 18"

You won't regret this decision. Having a 36" oven will give you room for a live fire, and a couple of cooking positions. This is how you adjust cooking temperatures. With a 32 inch oven, you will spend all your time trying to get a small enough fire, yet hot enough fire for your single cooking position.

There's no reason at all to go any higher than hemispherical.

[david s]

Re: My 32" oven build has begun

The heat up time hardly varies with oven size. They all take about 90 mins. The smaller the oven, the smaller the fire. It is the thickness of the walls and floor that is the determining factor. You are committed now you've laid the foundation slab, but in Australia most councils require Amin. Of 1.5m from your boundary fence, presuming that fence is your boundary. this only becomes a problem if you have neighbour issues and they want to get technical and use the law against you, so cultivate them carefully.

[OscarA]

Re: My 32" oven build has begun

Thanks guys you have convinced me to go 36".
I'm going to use standard firebricks so the oven wall will be around 4.5" thick.

in Australia most councils require Amin. Of 1.5m from your boundary fence, presuming that fence is your boundary

I did think about it and should have made sure. I know in my area (we just built a few years ago) you can build a house 1m from the fence, have a garage on the fence line and most sheds I've seen are close to the fence line.
I have given the oven roughly 500mm space from the fence and hopefully no issues arise.

[david s]

Re: My 32" oven build has begun

When you do your curing fires your oven WILL smoke and not fire too well. A good idea is to give your neighbours some pizza or a loaf of fresh bread as soon as possible. Once you've learnt how to control your fire you should be able to fire it virtually smoke free especially if you use the top down method at start up.
Good luck,
Dave

[OscarA]

Re: My 32" oven build has begun

Thanks for the tip.
There is one neighbour I worry about as everytime I do a BBQ smoke heads towards their decking the wind seems to go that way most of the time.
They know I'm building the oven and are fine but a little curious about the size of it as my stand looks huge. The other day she asked me if I was planning on feeding the neighborhood. I showed her the template of the oven floor when she jumped in and said that's right the walls are really thick aren't they That gave me the impression she knows a little about WFO's. I'll do the right thing and warn them about the initial firing and let them know the smoke is because of the wet oven and will be minimal once the oven is dried.

[stonylake]

Re: My 32" oven build has begun

Hi Oscar... looks like a great start. i built a 36", with a full brick soldier course and my dome "grew" to just under 21". my door opening ratio is .57 which is smaller than the recommended .63, but it draws fine. once the oven is curred, you can start fires fairly quickly (i use a small propane torch), and smoke won't be an issue

[bigred]

Re: My 32" oven build has begun

all of the above are great recommnedations....I built a 42" and let me tell you....the extra room is great for temperature management...and baking large things like pigs and turkey....which believe me ...you will want to do. One thing that I have discovered is to reaaly heat the oven up for more than the 90 minutes even though the temperature is right. Then le ti cool down... The reason is that the temperature of the floor hold up better for making a lot of pies. It is saturated thru ... I can go 10 pie without having to reheat floor and yet I wont burn the top of the pies because the required fire to keep it up is not that large, one last thing.....I recommend moving the cloths line in the picture before your first fire LOL....

[OscarA]

Re: My 32" oven build has begun

Thanks Stonylake and Bigred.
I'm now going 36" visually it's not much larger than 32" but the extra room should make the oven easier to cook in. In reality 32" is all I'll need 95% of the time but if larger is easier and I have the space then it's a no brainer.

I recommend moving the cloths line in the picture before your first fire LOL....

The cloths line is being replaced with a more compact line in a different location, lol.

[david s]

Re: My 32" oven build has begun

Generally the larger the oven, the greater will be the mass and the volume of the interior, which in turn will translate to higher fuel consumption. "What you gain on the roundabout, you lose on the swing"