Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

[Tenorio74]

Hi everyone,

I've been using grotesque amounts of wood (for me) to get my dome white, and something tells me I'm not on the right track. My oven is as stated 51" internal, low 18" dome.

I have 2.5 inch firebrick floor with 2" ceramic fiberglass board underneath, and about 6" in the dome (artisanal red "burnt" brick), covered by a lot (didn't count the inches) of fire blanket, covered in mud.

I admit I am only on about my fourth proper firing after curing it: 2 proper, then a two week break because I had to replace the floor (that's in another post), and two more after that. I'm going for my third later, but I must have consumed yesterday about 60+ pound of mesquite wood in my 2 hour run to clear the dome (didn't quite get there totally)... that's about one rice sack full of wood (that's how they sell them down here.

Would you guys say this because:
1. It's a relatively large oven (although I have the low 18" dome)
2. The moisture is not fully driven out of my hearth yet, which is super thick
or
3. I'm not building big enough fires for long enough.

I do get "scary" big, but can't maintain them like that for very long - it would either require quite a bit more wood, or really tending to and rearranging the logs, beacuse they produce tons of coal that never burns and basically sits underneath the fire.

Am at my wits end. And I'm off now.

Thanks for any quick replies.

[Tman1]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

You don't state how you did the curing fires. My guess is too much moisture still in the oven.

[Tenorio74]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

Tman1,

I did the series of small fires, newspaper,kindling 1, etc.

After those, I lit up. But had to replace the floor which was bogus. I've just started again, am going for my third big fire today (and am taking a couple of dough balls just in case)

[Tenorio74]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

Tman1,

I did the series of small fires, newspaper,kindling 1, etc.

After those, I lit up. But had. to replace the floor which was bogus. I've just started again, am going for my third big fire today (and am taking a couple of dough balls just in case)

[lwood]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

Assuming your door height is correct (11.34" for a 18" dome) it's most likely water being driven out of the dome. I have a 60" ID oven with a low dome and my dome clears in about two hours. It takes about 2 cubic feet of wood to get there.

[Laurentius]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

I really don't think that the wood you are using has a high BTU rating. We normally use Mesquite for barbecue and smokers for its flavor, rather than a true fuel source.

[Tscarborough]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

Mesquite has a high rating, it has to be moisture.

[dmun]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

Yeah, I vote for wet insulation. If true, your oven will get better and better. I'm not fussy about the wood I use until right before pizza cooking time. Get some skids, bust them up, and build some really big fires. 51 is a really big oven, and buying firewood by the bag will get you broke quick.

[Tenorio74]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

Assuming your door height is correct (11.34" for a 18" dome) it's most likely water being driven out of the dome. I have a 60" ID oven with a low dome and my dome clears in about two hours. It takes about 2 cubic feet of wood to get there.

Lwood,

My door height is 11" H x 19.6" W. It seems to work like a charm.... My chimney and draw seem to be doing their job properly as well.

Yesterday, starting from a slightly warmer oven (about 200F floor temp), I got a massive fire after about 30 mins, and got my dome partially clear in an hour, totally clear (what a sight to see!! ) in about 1:20-1:30.

I think I still have moisture in the hearth & stand, as they got warm (105?F) when I was up to temp (I have soil in my hearth under my ceramic fiber board).

Still used about 30kg of wood to get there, though it was much easier to get lit up. Can you help me out with the cubic feet conversion? We use the metric system down here, and wood is sold by kg or ton. How many cubic feet are in a ton?

Do you use your oven commercially? Mine is in my soon to be opened pizzeria.

Cheers,
Tenorio

[Tman1]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

30kg 's of wood!!?? Wow, thats' 66 pounds! Gotta be moisture. If a 30" dome takes almost a week of curing fires, I'd imagine a 51" would take more. I'd say forget going nuclear and just keep a fire going for a lonnnnng duration. That 30 kg's should last a while if you just keep it low and slow.

If you're going to be commercial, maybe you want to consider a propane torch/burner of some sort to help aid in the start-up process (if propane is cheaper). The mesquite should be really good for the purposes.

[Tenorio74]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

Mesquite has a high rating, it has to be moisture.

Yeah, I vote for wet insulation. If true, your oven will get better and better. I'm not fussy about the wood I use until right before pizza cooking time. Get some skids, bust them up, and build some really big fires. 51 is a really big oven, and buying firewood by the bag will get you broke quick.

I'm down in Peru, and the coastline is a desert region (so we don't have free wood available ).

Commercially, I have only found eucaliptus and algarrobo (which I can best describe as mesquite, being the same genus - Prosopis)

I have roughly calculated about a ton/month for my operation, which will run me about $300 (a bit more than I originally planned, I think I went a couple of inches big on the diameter.... I went from 47 to 51 last minute. Now I think it's going to cost me.... )

[Lburou]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

I'm down in Peru, and the coastline is a desert region (so we don't have free wood available ).

Commercially, I have only found eucaliptus and algarrobo (which I can best describe as mesquite, being the same genus - Prosopis)

I have roughly calculated about a ton/month for my operation, which will run me about $300 (a bit more than I originally planned, I think I went a couple of inches big on the diameter.... I went from 47 to 51 last minute. Now I think it's going to cost me.... )

Tenorio, I'm a beginner too, but, have noticed several people with similar reports early in the life of their ovens....I predict it will get better and better as the moisture levels fall and you have more heat remaining from the fire of the previous day.

The more oven heat carried over from the previous day the better it is for you....What kind of oven door do you have? A good, insulating door would save you a lot of wood burning. There is a good oven door thread here and here

Keep us informed of your progress please.

[Tenorio74]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

Tenorio, I'm a beginner too, but, have noticed several people with similar reports early in the life of their ovens....I predict it will get better and better as the moisture levels fall and you have more heat remaining from the fire of the previous day.

The more oven heat carried over from the previous day the better it is for you....What kind of oven door do you have? A good, insulating door would save you a lot of wood burning. There is a good oven door thread here and here

Keep us informed of your progress please.

Lburou, thanks for the encouragement! If it wasn't for you guys and this forum, I'd feel adrift at sea...

After last nights firing (dome well over 1000F, floor got to about 800+), shut the oven 9pm and this morning at 9am, the temp was 350/300 dome/floor, so I'm guessing I really didn't soak the heat in. (I have an iron door which get pretty hot, so I guess I'll have to attach insulation on the outside somehow).

However, this morning the exterior is warmer than last night during firing

The dome temp which never went above 98?F was 107?F in places, and the underside of hearth was (an is @ 11:02am) 112?F.

I guess I'll have to keep firing and see. I guess I'm on fire #5 after curing, so I'll give myself a few more runs like last night before worrying to much about wood costs.

Although I did make my 90 second margherita pizza!! It turned out great, so at least I got that right. Now I just have to soak the heat properly to maintain the floor temps....

[dmun]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

However, this morning the exterior is warmer than last night during firing

Yep, that will happen. The heat has to go somewhere. My support slab remains cool when i'm cooking, but the next day it will be warm to the touch.

Your oven performance will get better and better in the first month of firings, and as long as you keep it dry. You're in the Atacama desert? The place where it's never rained ever? That shouldn't be a problem.

[Tenorio74]

Re: Amount of wood to fire a 51 inch (130 cm) oven to pizza temps?

Your oven performance will get better and better in the first month of firings, and as long as you keep it dry. You're in the Atacama desert? The place where it's never rained ever? That shouldn't be a problem.

Atacama is down south, mostly in Chile but we get some of it. We get on average about 1 inch of rain per year, blah I wish it were more. However, my oven is indoors in my soon to be opened pizzeria, if I can work out the kinks