A question about wet ashes and iron stoves...

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chatta

New Member
Jan 18, 2016
4
Pensacola, FL
I have a wood stove I put outside, on a slab, out in the weather. (I live in the Pensacola, FL area, so there wasn't much use of me putting it inside the house.) Anyway, I have it set up, with the pipe and all (cap on top), and have been cooking on it outside. Well, it was after the last rain that I finally thought about the ashes in the stove, and them getting wet... wet ashes will make lye!!! Will that lye eat through the bottom of my stove?
So, off to the internet I went, looking for answers. Okay, wet ashes turn into lye... That kind of lye is called caustic potash---potassium hydroxide. So, does anyone know if potassium hydroxide will corrode my cast iron? If so, any idea how fast? Thanks.
 
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sorry sir, not a clue. someone will be by i'm sure that will be able to give some insight to your question.
 
I have a wood stove I put outside, on a slab, out in the weather. (I live in the Pensacola, FL area, so there wasn't much use of me putting it inside the house.) Anyway, I have it set up, with the pipe and all (cap on tap), and have been cooking on it outside. Well, it was after the last rain that I finally thought about the ashes in the stove, and them getting wet... wet ashes will make lye!!! Will that lye eat through the bottom of my stove?
So, off to the internet I went, looking for answers. Okay, wet ashes turn make lye... That kind of lye is called caustic potash---potassium hydroxide. So, does anyone know if potassium hydroxide will corrode my cast iron? If so, any idea how fast? Thanks.


Just guessing, but I think lye attacks organic matter, not metal. As I recall, Drano, which contained lye, came in a metal can with a plastic lid. It dissolved the hair clogs in your sink, not the metal pipes or the can.
 
Your stove will not last all that long outside. I use one outside on the patio and they typically last 2 to 3 years.
 
Thanks for all the input. I never thought of Drano... But, isn't Drano in a crystal form in the can? It seems like it would have to get wet to activate its properties on a surface.
 
Did some more searching on the web, and it seems that Drano has a hard time dissolving iron. Which makes sense, as Drano would have a hard time selling their product if it had been making holes in iron drain pipes for the past 75+ years. So, I think I'm safe with the bit of Lye which might be sitting in the bottom of my wood stove.
 
I thought lye was sodium hydroxide? Either way, I've watched sodium hydroxide gobble through aluminum and liquefy it in no time flat. I'm sure steel will last a bit longer than that.
 
I wouldn't worry about the lye, but if you have wet ashes constantly setting in the bottom of the wood stove it will rust it out.
 
Heat accelerates oxidation. Put a cover over the stove to protect it from the weather or it will be gone in a few years.
 
Heat accelerates oxidation. Put a cover over the stove to protect it from the weather or it will be gone in a few years.
Yes i don't cover mine and they typically start to fall apart in 2 or 3 years. But i don't care much they would be in the scrap yard one way or another i just use them a little longer before they go.
 
I ended up setting it up outside with a simple way to lift the 6" pipe off the top of the stove. I have a large, black, concrete mixing tub I put over the top of the stove. When the rain clears up (it happens to be raining here today) and it's sunny, I'll see how well it kept the rain away from the inside. If I have to, I'll look around for a cheap gas grill weatherproof cover. I think I'm going to need something that doesn't just cover the top, but all 4 sides too.
 
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