Average # of logs to achieve 700 degrees F

[ThermoJax]

Could some experienced members talk about the average number of logs they use to get up to temp. I am using a small fireplace grate with 6-8 logs. I burn that then add 6 or so logs, this time using the wife's hairdryer to blast the logs. I am not sure the the fireplace grate is helping, but my gut says yes. Maybe it helps me use less logs.

[Tscarborough]

Re: Average # of logs to achieve 700 degrees F

I use about 4 cubic feet of wood to fire to temp, then 4-5 more wrist size pieces for the side fire. The storage area under my oven is, by chance, just about right for a firing.

[shuboyje]

Re: Average # of logs to achieve 700 degrees F

How do you define a log? Going by what I would call a log that sounds like a huge amount of wood, but I bet we are talking in different terms.

[shuboyje]

Re: Average # of logs to achieve 700 degrees F

I like the idea of comparing in cubic feet. I just checked the package of wood I've used in a pinch, and with that I can get my oven to 900+ on the hearth and mantain that for longer then I've ever tried with that wood, but at least an hour. The package is 2 cubic feet. That said my oven is small and light. It's a 30" naples style low dome with 2.25" of mass in the soldier and floor , 3" in the dome.

[david s]

Re: Average # of logs to achieve 700 degrees F

I weighed the wood consumed by my oven once and it came to 4Kg to reach 350 C

[david s]

Re: Average # of logs to achieve 700 degrees F

I think weight of wood consumed is a better measure. How big is a log? Very inaccurate measure using volume. Also dense timber will give off more heat and take longer to burn. My oven is quite small so uses very little fuel.

[uk_exile]

Re: Average # of logs to achieve 700 degrees F

Wet wood weighs more though and would give off less useful energy than lighter dry wood. No easy to compare

[RTflorida]

Re: Average # of logs to achieve 700 degrees F

This is a tough one. I have never countedthe number of logs. I did do something yesterday a bit out of the norm.
I used nothing but 1 x1, 1x2, and 2x2 pieces of kiln dried poplar cutoffs from a mill shop.I know I loaded 6 handfulls (using both hands together), about 10 -15 pieces in each handfull. I was able to burn the dome clean in just over 1 hr, a bit slower that my usual 50 minutes with hardwood logs.I was surprised at how big a fire I got and the temp it produced. I really only built this fire to drive out any moisture after 2 days of rain. A waste of a fire (I did not have anything suitable for WFO cooking) so I used nothing but the stinky, black smoking poplar that I usually onuse for fire starting. I was impressed. Usually I use a bit of the small stuff then aound 15 logs in 2" -4" diameter.
Other then the stench of the smoke, I have no problems using the poplar sticks to get it up to temp.

RT

[david s]

Re: Average # of logs to achieve 700 degrees F

"Wet wood weighs more though and would give off less useful energy than lighter dry wood. No easy to compare"

Actually wet wood would still give off the same amount of energy, the trouble is that some of that energy is used up converting the water to steam.

We all try to avoid using wet wood for this reason. I still feel the wejght is a better measure of fuel used. How long is a 3''log? There is also a great difference in the energy contained between hardwood and softwood. The weight measure factors in all these differences.

[mn8tr]

Re: Average # of logs to achieve 700 degrees F

Start with a stack of 6 with kindling. At around 50 min to 1 hour add 2-3 more and start cooking.

[GianniFocaccia]

Re: Average # of logs to achieve 700 degrees F

I wonder how much longer it would take to bring an oven in 40F ambient to 700F than an oven at 80F ambient?

[Tscarborough]

Re: Average # of logs to achieve 700 degrees F

In the US, wood is measured and sold by volume. For firewood a cord is 128 cuft, or about 30 firings of my oven. "Board feet" is also a volume measure, and that is how lumber is sold. Both cord wood and lumber have specified amounts of moisture, and of course, hardwood and softwood are priced differently. For cord wood, "dry" is around 12% and "green" is around 50% moisture by weight.

[Tscarborough]

Re: Average # of logs to achieve 700 degrees F

I haven't noticed any difference in bring it UP to heat (from less than 40 and more than 100 ambient), but it does affect the cool down time by hours.

[HeidiL2011]

Re: Average # of logs to achieve 700 degrees F

Hello,


It depends on the size of the oven, but a Casa2G90 will completely heat up with 4-5 logs, and you add a small piece of wood (about 2"x4") every 20 minutes to keep the oven at high heat.

[Lburou]

Here is a youtube demonstaration to answer the question

A picture in this case would be worth a thousand words...

Jim, or jcg31, does a good job of communicationg how much of what kind of wood it takes for his oven, via Youtube