Clinkers

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Easy Livin’ 3000

Minister of Fire
Dec 23, 2015
3,018
SEPA
What kind of wood leaves the most clinkers? I had a bunch left from last night, but I had at least three kinds of wood that I burned, so I don't know which they came from. Not to be confused with coals.
 
The most? I do not know.......but I do get them when I burn straight ash and I do not get them when I burn straight maple.
 
The most? I do not know.......but I do get them when I burn straight ash and I do not get them when I burn straight maple.
I think I remember a discussion on here a long time ago that clinkers form from mineral/dirt deposits trapped in the bark. Perhaps, it's trapped in the furrows of the ash bark. Of course, I'm assuming the bark furrows on your ash splits are much deeper than those on your maple ones.
 
Ash and to a degree - elm, in my experience. Not sure how much truth is involved, but I have heard that ash has a tendency to contain more silica. Could be an old wives tale, but seems to follow the whole "clinker" discussion.
 
Ash and to a degree - elm, in my experience. Not sure how much truth is involved, but I have heard that ash has a tendency to contain more silica. Could be an old wives tale, but seems to follow the whole "clinker" discussion.
That makes sense. There could be a lot of trapped sand in there.
 
Yes, elm leaves a lot after it is done burning. I had a lot of stuff that looked small chunks of cement. Very light, could break apart with your fingers. I read somewhere there is a lot of silica (sand) inside the wood itself.
 
I get those every once in a while- but I can't pin it to a specific type of wood as its always a mix.
 
Well.... if it helps .... I've had a few "clinkers" lately, I guess? Patches of ash that act like old, melted beer bottles in a bottom of a brush fire? The theory of silica intrigues me because this wood is from a couple of thorny locusts that came from the banks of a sand-bottomed creek. Some of the best burning wood ever- and I'm not complaining. But since you all brought it, it kinda makes me wonder why I'm getting some clinkers now.
 
I am burning mostly oak, with some and pine.

I don't think clinker output tracks with wood species; I feel like it tracks outside temperatures. We get a cold snap, I run the stove hot for 24 hours plus, I know I'm going to see some clinkers.

On the other hand, when it's coldest, I tend to burn only oak on my work days, and mostly pine on my days off... So I guess my wood usage kind of tracks the weather too.