Here is my guess as to what is going on: a solution of ammonium chloride is painted onto the surface of the wood leading to ammonium chloride being absorbed into the surface wood fibres. Ammonium chloride decomposes to ammonia + hydrogen chloride above 340C. Heating with the heat gun achieves this temperature (which is why it takes a while in the video). Either gas (or both) causes darkening of the wood revealing the design.
Here is my guess as to what is going on: a solution of ammonium chloride is painted onto the surface of the wood leading to ammonium chloride being absorbed into the surface wood fibres. Ammonium chloride decomposes to ammonia + hydrogen chloride above 340C. Heating with the heat gun achieves this temperature (which is why it takes a while in the video). Either gas (or both) causes darkening of the wood revealing the design.
Heating surface with an application of $\ce{NH4Cl}$ results in the release of gaseous $\ce{HCl}$ and especially $\ce{NH3}$, which per Wikipedia on ammonia fuming, to quote:
Ammonia fuming is a wood finishing process that darkens wood and brings out the grain pattern. It consists of exposing the wood to fumes from a strong aqueous solution of ammonium hydroxide which reacts with the tannins in the wood. The process works best on white oak because of the high tannin content of this wood. Fumed oak is also called smoked oak.
Heating surface with an application of $\ce{NH4Cl}$ results in the release of gaseous $\ce{HCl}$ and especially $\ce{NH3}$, which per Wikipedia on ammonia fuming, to quote:
Ammonia fuming is a wood finishing process that darkens wood and brings out the grain pattern. It consists of exposing the wood to fumes from a strong aqueous solution of ammonium hydroxide which reacts with the tannins in the wood. The process works best on white oak because of the high tannin content of this wood. Fumed oak is also called smoked oak.
Thanks. If that is the explanation then ammonium carbonate could work too. Here in Sweden the chloride is a bit more difficult to buy, whereas the carbonate you can buy in any food shop (ammonium carbonate is used as a raising agent when making cookies). I do have some doubts though regarding the ammonia fuming being the explanation, since it seems to take a long time to affect the wood so that it actually looks burnt. But, of course, in that method heat is not applied, whereas in the method we discuss the temperature is a few hundred degrees Celcius, so perhaps the process speeds up.More
Here is my guess as to what is going on: a solution of ammonium chloride is painted onto the surface of the wood leading to ammonium chloride being absorbed into the surface wood fibres. Ammonium chloride decomposes to ammonia + hydrogen chloride above 340C. Heating with the heat gun achieves this temperature (which is why it takes a while in the video). Either gas (or both) causes darkening of the wood revealing the design.
This seems to be backed up by the explanation here: https://hackaday.com/2011/05/16/chemical-wood-burning/
Here is my guess as to what is going on: a solution of ammonium chloride is painted onto the surface of the wood leading to ammonium chloride being absorbed into the surface wood fibres. Ammonium chloride decomposes to ammonia + hydrogen chloride above 340C. Heating with the heat gun achieves this temperature (which is why it takes a while in the video). Either gas (or both) causes darkening of the wood revealing the design.
This seems to be backed up by the explanation here: https://hackaday.com/2011/05/16/chemical-wood-burning/
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Heating surface with an application of $\ce{NH4Cl}$ results in the release of gaseous $\ce{HCl}$ and especially $\ce{NH3}$, which per Wikipedia on ammonia fuming, to quote:
I trust this helps.
Heating surface with an application of $\ce{NH4Cl}$ results in the release of gaseous $\ce{HCl}$ and especially $\ce{NH3}$, which per Wikipedia on ammonia fuming, to quote:
I trust this helps.
More
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