How much heat can wood support?

[squirrel]

Hi,

is there anyone who knows at what temperature wood will start to burn?
I mean: if I put a wood like birch (dense) or a wood like oak or pine in a oven ... at what temperature do you think it will start to burn?

Sure it will make a difference wheter the wood is massif or hollow ... let us say it is 6 cm thick or thicker.

At 400 degrees, at 750 degrees, or even higher 900 -1000 degrees celsius?
I'm talking about electric heat, not about burning flames touching the wood.

squirrel.

 

[john lucas]

you peaked my interest so I did some reading and apparently it's a pretty complicated question. However to narrow it down I found this.
The pyrolysis of wood is dependent on external factors, such as the way of heating, warming-up rate of the material, etc. Therefore, wood products do not have an explicit ignition temperature, but ignition takes place on a certain temperature range where the probability of ignition becomes large enough. The temperature for the piloted ignition of wood is typically about 350 °C, whereas the spontaneous ignition requires a temperature of approximately 600 °C.
A rough conversion is 575 to 1000 degree farenheit.

 

[Barry Elder]

The pros can answer this for you, but I was told in a prior life that wood does not burn, it merely gets hot, releases gases, and the gases ignite and burn.

 

[MichaelMouse]

Ah Ray Bradbury, where are you now? 451F is a pretty good place to pick.

Pyrolysis takes place in an oxygen-poor atmosphere precisely because we're interested in obtaining the volatiles (and flammables) as liquids, not burning them as gases.

If you're interested in energizing the system well enough to unbind the water, I'd suggest the dry kiln operators' 150F as a good place to start. Won't harden the surface while the center's still wet. Of course, you'll want to do the conversion to 65C to check.

 

[hughie]

Ah Ray Bradbury, where are you now? 451F is a pretty good place to pick.

was thinking the same thing

 

[Ron Sardo]

Ah Ray Bradbury, where are you now? 451F is a pretty good place to pick.

LOL you beat me to it!

 

[Don O. Jr.]

451

If I'm not mistaken, 451 degrees F is the ignition point for paper not solid wood. Ray's book was about burning books not boards.

 

[john lucas]

I just found this.

Fire needs fuel, oxygen, and heat to survive. In forests, the fuel is provided by trees and bushes. In houses and buildings, the fuel is wood, furniture, books, and papers. Oxygen is not hard to find, seeing as it is all around us in the air. And without heat, the fire could not continue.

When wood reaches 572º, it gives off a gas which reacts with oxygen to make a flame. The flame will heat the remaining wood, making the fire grow stronger. This will happen even on cold days. The temperature at which something ignites is called its flash point. Paper burns at 451º Fahrenheit. Socks don’t burn until the temperature reaches 600º. Every material, even iron, has a flash point.

 

[Ron Sardo]

I think a more important question would be why would a person would need the exact temperature?



( I thought using, Fahrenheit 451º was a pretty good pun Two points to MM)

 

[john lucas]

It would be handy to know if your applying pewter since it has different melting points. I personally wanted to know because I have some friends who are glass artists and they have been playing with powder coating. The material has to be heated to 400 degrees to apply the coating. Now that I know the approx. flash point and it seems safe for this process I'm going to get with them and give it a try.

 

[Ron Sardo]

It would be handy to know if your applying pewter since it has different melting points. I personally wanted to know because I have some friends who are glass artists and they have been playing with powder coating. The material has to be heated to 400 degrees to apply the coating. Now that I know the approx. flash point and it seems safe for this process I'm going to get with them and give it a try.

Yes, you are right John.

Is this what squirrel is doing? I was asking him the question.

 

[Ken Grunke]

I just found this.
Socks don’t burn until the temperature reaches 600º. Every material, even iron, has a flash point.

I think human flesh is much lower than 600 F, at least for me. When smoke starts to waft out from under my hat, I know it's time to stop thinking so hard for a while

 

[john lucas]

Ken I start fuming much lower when I'm in my car. Irrational drivers, especially those on the cell phone, hit my flashpoint way too quickly. Apparently there are warning signs when a flashpoint is reached. I have a single digit that flies up as a warning sign to others. I really need to control that reflex.

 

[Ken Grunke]

John, I'm glad it's only a finger that goes up and not something metal that it wraps around

 

[Richard Baker]

According to my thermocouple, oak chips (the "sawdust" from a sawmill with a big circular blade) will char at about 450F. At the time I was trying to avoid having them burst into flame, and did not observe at what temperature that would happen.

 

[squirrel]

Hello,


yes, indeed. I have some knowledge about ceramics and glass. I have a kiln so I was thinking that, if the flaming point of wood is high enough, it must be possible to combine glass and glazes and wood.
But I have to know the exact temperature because if the temperature is wrong .... and the wood will get in flames ... my ceramic kiln will be ruined.
Thanks and hear you later.
Squirrel

 

[squirrel]

for john lucas

No John,
I do not use pewter.
My thinking is that if the ignition of wood is lower than the meltingpoint of by example enamels, glazes and substitutes and glass and substitutes , it must be possible to bind wood with one of those.
So, no pewter.

Squirrel

[mod note: I moved this from the thread "washcoat:1-pound cut shellac" where Squirrel accidentally posted it. Ken Grunke]

 

[Ron Sardo]

Looks like you where right John

squirrel, most kilns I know about are to hot for wood

 

[Barbara Gill]

I just found this.
Socks don’t burn until the temperature reaches 600º. Every material, even iron, has a flash point.

Uhm John, what kind of socks...wool, cotton, blend, man made fiber?

 

[MichaelMouse]

Uhm John, what kind of socks...wool, cotton, blend, man made fiber?

Having seen what flaming polyester and nylon can do to skin, I'd advise removing your socks before you walk on the coals. You can't stop the burning.

There are char temperatures, ignition (spontaneous or non) temperatures, flash points, and more. The volatiles in the wood, if it is green, could easily flash below a temperature which would ignite the wood.

 

[squirrel]

reply to Ron Sardo

Hi,

no, kilns are not too hot for wood. Not necessary.
I can put it on every temperature I wish between 0 degrees and 1300 degrees. So, if I wish I even can use it for baking bread.

It is worth a try.
Squirrel.

 

[Steve Worcester]

But I have to know the exact temperature because if the temperature is wrong .... and the wood will get in flames ... my ceramic kiln will be ruined.
Thanks and hear you later.
Squirrel

It won't be ruined, the fire will just char the bricks (or fibre). The safest place in the shop is inside the kiln.

 

[Ron Sardo]

Hi,

no, kilns are not too hot for wood. Not necessary.
I can put it on every temperature I wish between 0 degrees and 1300 degrees. So, if I wish I even can use it for baking bread.

It is worth a try.
Squirrel.

Nice, A temperature control.

 

[Don O. Jr.]

Wood and Glazes

Hey Squirrel,

Pottery glazes melt way too high for use on wood in my opinion. My wife is a potter and she fires her glazes to cone 6 or 7 which is well over 2000 deg. F. That's for high fire stoneware, but even low fire earthenware fires around 1500 deg. F. or more.

Not sure what you are trying to accomplish, but ceramic glazes and wood probably won't work.

 

[Bill Boehme]

The pros can answer this for you, but I was told in a prior life that wood does not burn, it merely gets hot, releases gases, and the gases ignite and burn.

Only if you were making charcoal would that be true. Otherwise, what you describe is the first stage of burning in which the VOC's cook off and burn or are captured without burning. Next, the cellulose and lignin burn.

 

[squirrel]

Hello,


There are enamels which can be used in the daily breadkiln in the kitchen.
There are possibilities to lower the melting point of glazes (I know ceramists who did the first kiln at 1200 degrees C and the second: the glazes not more than 400 degrees.).

There are woodkilns, gaskilns and electric kilns. An electric kiln as mine is get damaged when the wood gets in flames: the electric wires are inside the kiln and they will melt when they come in touch with the flames.

Squirrel.

 

[Dave Roller]

I just found this.

Fire needs fuel, oxygen, and heat to survive. In forests, the fuel is provided by trees and bushes. In houses and buildings, the fuel is wood, furniture, books, and papers. Oxygen is not hard to find, seeing as it is all around us in the air. And without heat, the fire could not continue.

When wood reaches 572º, it gives off a gas which reacts with oxygen to make a flame. The flame will heat the remaining wood, making the fire grow stronger. This will happen even on cold days. The temperature at which something ignites is called its flash point. Paper burns at 451º Fahrenheit. Socks don’t burn until the temperature reaches 600º. Every material, even iron, has a flash point.

As does my wife!

 

[Steve Worcester]

There are woodkilns, gaskilns and electric kilns. An electric kiln as mine is get damaged when the wood gets in flames: the electric wires are inside the kiln and they will melt when they come in touch with the flames.

Squirrel.

The temperature of the wire is much higher than flames the wood would give off. That said, you probably aren't trying to burn up the wood.

There is a way to make a 3d form of the wood product out of refractory plasters, seal them so the glaze wouldn't seep in, and then put the glaze over the plaster and fire them. After that you could remove the glaze from the plaster and glue them to the wood.Similar to what I do with glass forms.