Experimental stove. Looking for self-build advice!

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Hey guys, pretty close to done. Needs some weld grinding and stuff like that.

Did a small test burn and the primary air doesn't seem to be close to enough. I might weld up some of the holes by the door and add some to the spot under the fire.

I am only running like 2 feet of chimney(for the test), will a longer run help very much or should I put in another 2"X2" of air?

Pics are with the door cracked as it doesn't run well with out that

View attachment 293740
It won't run right at all untill it's hooked to a chimney
 
Yeah, I'm more just wondering about the primary air and if I should increase it. With the door cracked and the short Chimney length I had the top baffle area burning and one of the towers burning so I'm happy ish with it.

It's more a concern of its a lot easier to cut and weld in another channel at home than at an off grid property using a generator. Not that it can't get done.
 
Yeah, I'm more just wondering about the primary air and if I should increase it. With the door cracked and the short Chimney length I had the top baffle area burning and one of the towers burning so I'm happy ish with it.

It's more a concern of its a lot easier to cut and weld in another channel at home than at an off grid property using a generator. Not that it can't get done.
You really will have no idea how it's going to work without a chimney
 
Fair enough, I think the chimney will be over 10feet so it will probably make a significant difference,

Maybe I will grab 1 more length just to see if that changes somethings, I will need it at some point any way.

Thx for the advice.
 
Fair enough, I think the chimney will be over 10feet so it will probably make a significant difference,

Maybe I will grab 1 more length just to see if that changes somethings, I will need it at some point any way.

Thx for the advice.
The chimney really is the engine that drives the stove.
 
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Interesting.

I have no experience with wood stoves as most of my stuff has been rockets or tluds so this is pretty new.

Thx again.
 
Interesting.

I have no experience with wood stoves as most of my stuff has been rockets or tluds so this is pretty new.

Thx again.
Yeah a stove hooked to a chimney is going to have much more suction pulling through it.
 
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Maybe I will grab 1 more length just to see if that changes somethings, I will need it at some point any way.
2' more will help a bit, but until you get to 8-10' feet you really don't have much of a chimney (and even 10' barely qualifies)
As B said, it really is the engine that powers the stove.
 
Hey guys, pretty close to done. Needs some weld grinding and stuff like that.

Did a small test burn and the primary air doesn't seem to be close to enough. I might weld up some of the holes by the door and add some to the spot under the fire.

I am only running like 2 feet of chimney(for the test), will a longer run help very much or should I put in another 2"X2" of air?

Pics are with the door cracked as it doesn't run well with out that

View attachment 293740
To be fair, you have to have a good draft. If you were out in an open area 2 feet might work better. Looks to be an enclosed area where you are at.
I put 9' on my test

20220107_162622.jpg
 
I'd move it a bit away from the plastic on the eve for your next test...
 
Fair enough, I think the chimney will be over 10feet so it will probably make a significant difference,

Maybe I will grab 1 more length just to see if that changes somethings, I will need it at some point any way.

Thx for the advice.
in your out door test environment there could be many variables. keep the weather in mind before you make any determinations on your stove.
 
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Added 2 more feet of pipe and WOW what a difference.


That one is with the door ajar. You can see the air from the tower in the back shooting fire across most of the stove. With the door ajar the front tower does very little.

When it's hot and I close the door, the primary air holes by the glass seem to act as secondary burns. Thoughts?



I might try covering them and drill a few holes beneath the fire or shooting back because I feel like it's pushing the flames up and out more than helping them hit the secondary or third burn.


This video is with door closed and a brick in front of the primary air so it's a bit choked.



Even if I don't change anything or if the changes don't help, I would say this was incredibly successful.

Couldn't have done it without the help. Thanks everyone!
 
Looks like its got a turbo...lol.
Do your air controls keep the fire "in check" if you feel the need to slow it down ?
 
I haven't made the metal air control yet so I just put a brick in front of the air tube and it pretty much instantly shuts down those jets.

I need to change some of those holes. They are supposed to be primary but I don't think they are really feeding the primary.

If the baffle opening was at the back then I think it could be cool and functional.
 
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I haven't made the metal air control yet so I just put a brick in front of the air tube and it pretty much instantly shuts down those jets.

I need to change some of those holes. They are supposed to be primary but I don't think they are really feeding the primary.

If the baffle opening was at the back then I think it could be cool and functional.
Not sure where your design ideas came from but you have what looks like a heat monster shaping up. Could be above and beyond The EPA heat standards.
Keep us updated.
 
To be clear the EPA doesn't have any sort of heat standards at all. Just emissions standards.

By the looks of things I think you already have too much air. When you hook it to an actual chimney I am pretty sure you are going to have to plug lots of holes.
 

Air open


Primary close to off.

I drastically changed the primary air. Welded most of the primary air in front of the glass shut completely but left a few tiny ones that might help with air wash.

Drilled more holes facing the back to encourage the swirls. It definitely helps with that. The front jets now spit some fire in front of the glass.

I drilled some holes that are pointing straight up and I think this is now messing with the back jets.

Next refinements are:

Weld some angle iron over the upward jets to force the primary air sideways that is interfering with the back jets and create even more swirling.

Change the ceramic baffle so that the front of the stove is sealed and the exhaust path is in the center of the stove, this should also increase the swirling effect as the front side jet won't be able to exit quickly.

I tried to film my modifications however my phone didn't save them. I will try again next time I have the stove in the garage.
 
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Your wood looks confused as to where it will ignite next.
That is an amazing display. Good job,
Your have the entire firebox insulated on 3 sides and top?

I share your enthusiasm with the secondary burn I added to a 13 YO add on wood stove. Not as intense as yours but I can lay 2 or 3 fresh splits on a hot coal bed and it goes to immediate secondary burn much like your second video.
 
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Yeah I have seen some videos of mods. Do you have one? I have an older wood stove under a tarp out at the cabin so I might mod that one.

I used ceramic fiber board and then stuffed ceramic wool where ever there was a gap. I have 2 boards on top of the 3rd burn. I will shove them forward and add some at the back then cut a hole in the middle.

The other option would be to bore a few holes out of the top board so it has to go out in different places but I don't know how well that would work.
 
Have you asked your insurance company how they feel about you putting a home made stove in your house? I would want to be sure I would be covered in case something happens.
Yep. I rebuilt and modernized a stove for a guy and his insurance company turned him down. (I told him to check first, and he told me he did, but he didn't) now it sits unused in his garage
 
Yeah I have seen some videos of mods. Do you have one? I have an older wood stove under a tarp out at the cabin so I might mod that one.

I used ceramic fiber board and then stuffed ceramic wool where ever there was a gap. I have 2 boards on top of the 3rd burn. I will shove them forward and add some at the back then cut a hole in the middle.

The other option would be to bore a few holes out of the top board so it has to go out in different places but I don't know how well that would work.
LOL....UMMM nevermind.

Here is a link to to a thread on here I joined into back in Jan. I posted a few pics and videos of my mods as I went. my post starts #41.
 
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So the first baffle set up was terrible, the flame was able to just exit.


I pushed them together with a hatchet and WOW what a difference.


And then with the primary shut down it got really dark flames.


And then even darker with a brick infront of the 3rd burn


I will probably try more things but for a while I think this is good.
 
The secondary burn is very nice. This is a good, clear illustration of the function of the baffle. When the firebox (not stovetop) is over 1000º inside, cutting down the primary air to a minimum (just airwash) will create a vacuum that will pull air through the secondary manifold. This burns the gases most efficiently with the increased residence time created by the baffle slowing down and lengthening the flame path.