Planning my 32" cast oven

[AndreasP]

Warhorn6 ,thanks. There is so much information on this site I think you could look forever. Once you have a good understanding of what you want to do, start a build thread and if you're in doubt ask. I never had a problem getting my questions answered. This is a very supportive community.

[AndreasP]

You're absolutely right on the seasoning. I did split it, but it seems that in our climate (high humidity for much of the year) it does take more than a year to properly season Avodado wood.
It is getting better and better with less smoke. I guess I'll have to get some more wood, let it season for 18 months or so before I use it.

It also helped to burn smaller pieces, and I'm now starting out with a smaller fire, saves wood and doesn't take noticeably longer to heat up. Makes sense, the cold oven can only take up so much heat at a time.

Thanks for all your help and advice, really appreciated.

[david s]

Wood requires seasoning, which really just means drying out. Because of the cellular structure of wood, this takes time, usually a year. I think the term seasoning comes from the idea that you need to wait a few seasons before it's dry enough. Splitting the wood will hasten the drying.

[Warhorn6]

You're oven came out beautiful. Can't wait to start on mine, just trying to soak up as much information as possible at the moment.

[AndreasP]

Did two more firings and it's definitely the avocado wood.
I started with smaller fires and used wood that was more seasoned. Much less smoke.

I'll have to just wait a bit longer with the Avocado wood to see if it improves

[AndreasP]

Thanks Kris, it's actually more the Avocado wood that's smoking for me. I'll try to start with a smaller fire.

[Kris S]

I don't use pine because it tends to give off a lot of smoke, which I noticed using our wood stove...

Pine tends to smoke a lot especially on igniting when the fire's not very hot yet, and even more so when you shove a whole load in the oven at once.
I also use the top down method to ignite the oven (and wood stove), but just a small bundle of wood to start with (in the centre, not under the entrance) and feed it a couple of sticks at a time until I have a big fire. with this method only the first 10 minutes there's some smoke that escapes, after that none at all.

[AndreasP]

My chiney is a simple double walled chimney, not insulated.

I currently use the top down method with a big stack that barely fits through the entrance. I'll try the small fire to see how it works.

I guess I'm happy I only added the door once the ceiling started clearing and tried to see how to keep the smoke from coming out the door.

In the end it's not that big a deal. I use Avocado and pine to start the oven and get it to temperature (free wood).

When I cook pizza I use almond wood which really doesn't seem to smoke (and wasn't free).

Thanks for all your help!

[david s]

Reducing the air intake will take the fuel:air mixture closer to optimum which will send the temperature rise soaring to around 300C/hr. This would be the equivalent of firing a kiln at full blast from ambient, which results in damage to the wares inside as well as straining the kiln’s refractory. The reason is that the temperature difference and resulting thermal expansion difference produces stresses that can result in micro (ones you can’t see) and macro cracking. Far better for the longevity of your oven (or kiln), to fire slowly (200C/hr) which allows the heat to penetrate slower without subjecting the refractory to excessive thermal expansion differences.

Regarding your smoke issues, you may find that simply keeping the fire quite small for the first 1/2 hr will prevent the smoke escaping. I learnt this technique years ago when I was at a market stall and the woman beside me had lots of hand knitted baby ware. Smoking them out was a serious concern, but keeping the fire quite small at start up worked well.

[fox]

Is your chimney insulated?

[AndreasP]

Had another pizza gathering last weekend.
I Keep having problems with smoke coming out the front opening, especially while firing up the oven (first half hour or so). I do light the fire in the entrance underneath the chimney to get the draft going for a few minutes.
How long do others keep the fire there?

I think my 3ft chimney could be a bit taller, it is 6" diameter, but I didn't really want it to stick up over the fence, and adding an extension would not look very nice.

Last weekend it a bit breezy, so I placed the door on top of some bricks so that there is a small gap at the bottom. This forced the smoke through the chimney and seemed to work really well.

I think I used less wood to heat the oven and the oven was ready a bit faster (kind of makes sense with the door added).

I attached a picture.

Any thoughts on if this is a good or bad idea? Any concerns?

Andreas

[AndreasP]

I would certainly do that, but at the moment they are all just coming to our house to have pizza.

[david s]

I was thinking you might want to help a friend build one.

[AndreasP]

David, yes, I completely agree. Without the help from this forum my oven would never have turned out the way it did.

Not planning on building another one for now though, unless we move (no plans there). It's a lot of work and I have run out of space. This oven was already quite the squeeze.

[david s]

Now you've caught the oven building and cooking bug, when are you going to build the next oven?
You've done a fantastic job for your first one and thanks for sharing your journey. One of the greatest things about this forum is that folk are keen to share all their secrets documenting experience and experimentation for the benefit of others. It's a wonderful opportunity kindly provided by our Forno Bravo hosts.

"Fire turns man into a philosopher"