# Forum Home Renovation Metalwork & Welding  Rocket stoves

## PlatypusGardens

Ringtail says I should build one....  :Roll Eyes (Sarcastic):  
Well....they do seem interesting....hmm  
Who's built one? 
What's the best setup?
(...some feed the wood straight in while others down and in at an angle)    
Maybe (If I do build one) I should just stick to the straight in, right angle setup as I do have a tendency to over complicate things.
*sigh* 
 Although some setups seem to cosist of a couple of paint tins, or even besser blocks...  :Shock:            
Also came across this....the..."Dakota Fire Hole"      :Biggrin:

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## ringtail

Vertical feed is best I've found. The idea is too only burn the tips of the timber and the fuel load self feeds as it burns down.  If the fuel load is on an angle the flames tend to lick up the length ( said the actress to the bishop) and the fuel doesn't last as long. Also, forget burning big bits of timber. They are meant to run on small, long stuff. Basically rubbish wood. Pine cones work great though. The formula, from memory is burn chamber is 1.5 x the length of the feed tube and the flue must be at least 2x the length of the burn chamber and vertical. All components must be the same section. Bulk info on youtube but beware the knobs. I'll find some links for you.

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## Uncle Bob

I've been looking at building one for the place down the coast. I'd like a small footprint yet big enough to take a load other than sticks (IE; no wood spitting except kindling). Those criteria pretty much rule out most of the designs I've seen. 
This one is certainly eyecatching...

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## ringtail

The whole idea of them is to use scraps, small branches or coppiced trees for near zero cost mass heating of off grid houses. I don't think they are really useful for a "legal application" in Australia. The seppos are trying hard to get them approved for houses but there are no construction standards for them, yet. Of course, off grid one can do as they please. They are great for heating large quantities of water quickly using very little timber and awesome for heating a large thermal mass for prolonged heat release. They are not very good to cook on as they burn with such ferocity your BBQ plate will glow red.

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## joynz

Who are 'seppos'?

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## PlatypusGardens

> I've been looking at building one for the place down the coast. I'd like a small footprint yet big enough to take a load other than sticks (IE; no wood spitting except kindling). Those criteria pretty much rule out most of the designs I've seen. 
> This one is certainly eyecatching...

  Looks awesome.
Shame the video was so rubbish. 
From the description:  

> How to make wood gas rocket fire stove boiler.  There is no need electricity power  it was only made by fire wood n wood pellet  Home made by Mang Ggong who is in s.korea  Give me your phone at any time if you want to know ....82-10-9425-4544

   :Unsure:

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## PlatypusGardens

> Vertical feed is best I've found.   
> The formula, from memory is burn chamber is 1.5 x the length of the feed tube and the flue must be at least 2x the length of the burn chamber and vertical.  
> All components must be the same section.

  
Right, so something like this then....     
Or this

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## PlatypusGardens

:Biggrin:  :Biggrin:  :Biggrin:

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## OBBob

Here we go again! Isn't Moondog some sort of Rocket Stove guru?? Pity he's presently on leave ...

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## ringtail

> Right, so something like this then....     
> Or this

  Yessssss !

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## PlatypusGardens

Or this   
A little one like that would be good for camping, burning driftwood etc   :Smilie:

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## PlatypusGardens

:Biggrin:        
Measurements are a bit "-ish" but seems to work                
That is so cool! 
Or hot...I suppose.  
Can't believe how long those little sticks of pine are burning.
Will add something around the top of the flue to sit a pot/pan on and see if I can cook over it.
seems hot enough

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## PlatypusGardens

Couldn't seem to keep it going for more than a short while so got rid of the vertical feed and trying the "straight in" approach...      
Works....just...far from roaring and rocketing though...  
hmm

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## OBBob

Marc would have some bellows kicking around wouldn't he ... or just right it up to the compressor - force fed oxygen.

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## PlatypusGardens

Well...I'm not sure, but I think I may have stuffed up on the measuring.
I measured the center part as the distance between the feed tube and the flue....but some pics I've looked at now they measure from the ends...so...gave it a chop    
Now ^ 
Before \/    
It definitely seemed to draw more with the vertical feed tube....for a while...so we'll see.  
I shall try it again later.   :Smilie:

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## PlatypusGardens

> Marc would have some bellows kicking around wouldn't he ... or just right it up to the compressor - force fed oxygen.

  
That would kind of defeat the purpose  :Rofl5:

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## PlatypusGardens

Boiling!!!!  
On the right track  :Biggrin:   
Think the flue could be a tad shorter   :Smilie:

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## OBBob

Adjustable flue next?

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## PlatypusGardens

One for Uncle Bob...build it in to the furniture   :Smilie:

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## ringtail

Cool PG. Casing the rocketyness is addictive. You can play with adjustable air inlets too  :Biggrin:

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## ringtail

> One for Uncle Bob...build it in to the furniture

  Yep, that's the idea. The fire burns up into the barrel giving radiant heat then the flue starts at the bottom of barrel and snakes its way through the earth mass couch before exiting the house. Burn the stove for 4 hours and heat the house for at least a day from the slow release heat from the couch

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## PlatypusGardens

> You can play with adjustable air inlets too

  Yeh I tried placing some steel plate over the opening but it seems to burn best without anything on it.   
Been looking at so many plans and instructables.....seems anything goes really...
Some say larger diameter burn chamber than flue and others the other way round.   :Unsure:

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## Uncle Bob

> One for Uncle Bob...build it in to the furniture

  I probably seen that one all ready  :Wink:  Zerofossilfuel made a good one that runs on pellets. But the cost of pellets puts me off. I prefer the cost of pallets instead  :Smilie:

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## PlatypusGardens

> the cost of pellets puts me off.
>  I prefer the cost of pallets instead

  
Hmm yes......gonna be a big stove.....

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## ringtail

PG, also have a look at "pocket rockets". Basically a 20 lt drum with 2 holes cut in the lid. One for feed tube, one for flue. PM me you email and I'll send you a video of mine in action.

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## Uncle Bob

> . Basically a 20 lt drum with 2 holes cut in the lid. One for feed tube, one for flue. PM me you email and I'll send you a video of mine in action.

  I wouldn't mind seeing it. Can you upload it to utube or something?

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## ringtail

I can do that. Not until Sunday night though when I get back from the farm.

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## OBBob

How about this... Jam jar pulse jet? It looks a little less 'stable'.  :eek:   https://youtu.be/sETrQwmd-n4

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## PlatypusGardens

> How about this... Jam jar pulse jet? It looks a little less 'stable'.  :eek:   https://youtu.be/sETrQwmd-n4

  
Bloody hell... 
Darwin awards are calling    :Rofl5:

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## PlatypusGardens

WTF   BioLite CampStove | Burn Wood, Cook Meals, Charge Gear    :Unsure:

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## PlatypusGardens

A few more adjustments....shortened the flue by about 100mm and added a little plate in the feed tube. 
Seems to be an improvement.        
Woooosh    :Biggrin:

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## OBBob

> WTF   BioLite CampStove | Burn Wood, Cook Meals, Charge Gear

  Yes, not cheap those. I sort of reckon camping is good without USB.

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## PlatypusGardens

Suppose it could be warranted if you're hiking or something like that. 
Pretty cool little setup really.   :Smilie:

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## PlatypusGardens

Someone sent me this     
....and there on the "Maxi" stove we can clearly see what ringtail was referring to with the flames licking the length etc....  :Unsure:   
ahem 
Anyway.  
This one, while crude and badly welded apparently works well...according to what I read anyway. 
The guy built it from scrap pieces and just used the lengths as they came, but reckons it gets red hot.   
 I think he might be on to something there with the slight angle feed but away from the flue...    
Specs here (in imperial.....of course  :Rolleyes:  )   
The RHS he used was 6x6" So it'd be quite heavy I imagine.....
[s]If I was to [/s] when I inevitably build a bigger one, I might do something like that.   :Smilie:    
I'm also wondering if this will improve the performance or mess with the airflow in a J-shaped setup....    
That ^ was from a large built-in unit in a house, not a freestanding little backyard thing.  
Will have to experiment a bit I reckon.      :Biggrin:

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## Marc

Mm ... extra air intake. it will slow down the air coming from the feeding tube. May be if you make it with a gate to regulate the opening.

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## PlatypusGardens

> Mm ... extra air intake. it will slow down the air coming from the feeding tube. May be if you make it with a gate to regulate the opening.

  
That's what I was wondering about too.....then again, some seem to have a lid over the feed tube....hmm...   :Unsure:

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## Marc

Yes, a lid with variable size hole but that would negate the choice of feeding long pieces of wood. Clearly if you can regulate airflow in any way you can fine tune the burning process. If it is fixed it will work at optimum only in one set of circumstances. All wood burning devices have one way or another to regulate the air.
Furthermore, if you say feed the fire with one little stick, the amount of airflow will be high. If you stuff the hole with lots of wood, the airflow is lower, so may be then you need to open the air intake below?

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## PlatypusGardens

Yes.....I think the idea is to control the airflow with the firewood....more or less...?  
anyway.
Onwards   
Having another go at the horizontal feed.     
The plan is to put this    
In one of these    
And fill it with sand as insulation = more heat in flue = better burn    
stay tuned   :Smilie:

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## PlatypusGardens

So I did that.....   
Cut the tank in half, cut holes for the pipes, got the rubber bladder out, welded it all together, lit it up    
Put a pot of water on top.... 
Spectacular failure.
Just would not work.
It almost seemed to be worse after putting it in the tank and sand.....     
So back to this one, which now has a bit of mesh to keep the wood upright. 
It works better when the wood is upright (said the ringtail to the cleaning lady)    
Boiled the pot of water in 13 minutes   
The J-shape is definitely a winner so far.    
That's all for now.    :Smilie:

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## Marc

Mm ... the sand is the problem, try without sand. The tank should act like a double flue, the sand only cools it down.

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## Uncle Bob

Yeah as Marc said. Perlite or fireproof rockwool is the go

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## Marc

Nee, nothing at all. The flue gets hot very quickly, what cools it down is the free air around it. heat radiates out and nothing comes back. If you pack anything solid against it you have contact. Heat travels better and all you achieve is a cooler flue regardless of materials used. If you have a second skin the heat reflects back and the flue temperature increases. Now I don't know if that is desirable or not but if you want to achieve a hotter flue all you need is a double skin. Not packing insulation on it.

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## PlatypusGardens

Noted. 
Will try that next.
Just that I saw some where they used sand etc as a filler....   
But what you're saying makes sense.
That drum is STILL hot, long after I put the fire out.
So yes....if anything it's soaking up the heat and drawing it away from the flue.  
This is all very interesting.   :Smilie:

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## PlatypusGardens

> If you have a second skin the heat reflects back and the flue temperature increases. Now I don't know if that is desirable or not

  
Yes that's what I gather.
Hotter flue, more burn, more heat, less smoke.....  
,.......right?    :Unsure:

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## ringtail

Been busy PG. The bug has bitten  :Biggrin:  . I'll try and find the vid I made of my " maxi" which was almost identical to his. Gabriele actually contacted me via youtube. I think he liked it but wanted credit

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## PlatypusGardens

> Been busy PG. The bug has bitten  .

  You know me.....everything becomes an obsession....for a while....   
nah seriously though, 
Definitely see a future in making and selling these if I can fine tune them.  :Smilie:  
Probably don't even need the second skin flue setup, but will try it anyway, just to compare.
But to be able to boil a billy in 12-15 min on a couple of little twigs is a good selling pitch right there I reckon. 
The second sking thing (when done right) will hopefully reduce the ash and coal buildup as well.   :Wink:       
This is all your fault by the way.

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## Marc

> Yes that's what I gather.
> Hotter flue, more burn, more heat, less smoke.....  
> ,.......right?

  well you be the judge of that, I only say that packing the flue with insulation of any kind will not work, not for a long time.Eventually may be but you don't want to build an oven, you want something that starts roaring straight away.

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## PlatypusGardens

> packing the flue with insulation of any kind will not work, not for a long time 
> you don't want to build an oven.

  
Makes perfect sense    :Smilie:

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## ringtail

> This is all your fault by the way.

  Totally. Mission accomplished  :Biggrin:

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## PlatypusGardens

> Totally. Mission accomplished

   :Slap2:

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## Marc

if you succeed with the right dimension and get it fine tuned, you can then make them into some sort of sculpture, say a dragon you feed through the mouth and that spits fire through the ears or ... well you get my drift  :Rofl5:

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## PlatypusGardens

> if you succeed with the right dimension and get it fine tuned, you can then make them into some sort of sculpture, say a dragon you feed through the mouth and that spits fire through the ears or ... well you get my drift

  
Oh yes   :Wink:

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## PlatypusGardens

Haha. 
Something like this?

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## Marc

Yes! Well that one would be hard to come close to but something similar ... with two heads?

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## OBBob

Sort of looks like it should be dynabolted down!

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## ringtail

> Yes! Well that one would be hard to come close to but something similar ... with two heads?

  The Tasmanian version  :Tongue:

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## ringtail

Still looking for these bloody videos. Not on youtube anymore so I may nave deleted them  :Doh:

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## PlatypusGardens

Three heads it is then.   :Biggrin:

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## PlatypusGardens

Well, been googling rocket stove and J-stove design, dimension, specs, proportions etc blah blah and come to the conclusion that there are no rules. 
Just keep trying until it works.    :Smilie:    
And on that note I'm off to bed

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## ringtail

Yep pretty much PG. Things I learnt were - additional air intakes need to be fully adjustable, definitely have a way to empty the ash, brick rocket stoves buried in the ground work heaps better than metal ones.  
Google ernie&erica , they are pretty much the rocket stove guru weirdos

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## PlatypusGardens

> Google ernie&erica , they are pretty much the rocket stove guru weirdos

  
Good website, thanks for the tip.   :Smilie:

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## Marc

Aaaaaah stop talking garbage pleeeeeeese and show something useful !!!!!! ernie and erica politically correct heating methods  :Smilie:

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## ringtail

Is your coffee machine broken Marc ?  :Biggrin:

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## Marc

> Is your coffee machine broken Marc ?

  Nee just watching their you tube videos, they are impossible ! Well unless you are a Tasmanian or Blue mountain dweller living off the taxpayer and with lots of opinions aobut refugees and indians and environment and ...

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## PlatypusGardens

I didn't watch any videos yet....hmm...

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## ringtail

They are full blown tree huggers for sure. They used to be very guarded and kept all their info on a paying basis until a bloke called Paul Wheaton ( you would no the name by now) bought them out of their hemp teepees a bit

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## ringtail

The permies forum has a whole rocket stove section too

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## PlatypusGardens

> The permies forum has a whole rocket stove section too

  
Yes I've found myself there a few times. 
Not watched a lot of videos as they tend to bore me, but that dutch guy with the rocket stove on steroids video (I think it was called) is pretty cool.   :Smilie:

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## PlatypusGardens

Anyway got me some 90x90 and am gonna knock up a bunch of little ones and see if I can flog them at the markets

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## ringtail

Cool. If you promote the " small amount of fuel for a lot of heat " and the "boil the billy using twigs" lines I think they would sell. Price point, as usual, will be the killer. Once the steel is cut and welded, consumables, gas, etc.... and your time I would say $80-$100 would make it worthwhile in its own right. However, if they generate sales of your other bits then $50-$60 could be in order. What were you thinking dollar wise ?

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## PlatypusGardens

$50-60

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## PlatypusGardens

I think I have enough steel there to make 8.
Steel was $30 
But only making 4 to begin with.

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## ringtail

Make 1, get it right then do a cutting list and have at it.

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## PlatypusGardens

:happy:

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## Uncle Bob

> 

  This post brought to you by the letter "J"  :Biggrin:

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## PlatypusGardens

> This post brought to you by the letter "J"

  
Indeed. 
And apperently this setup is to be referred to as a J-pipe stove, while the rocket stoves are the horizontal feed L-shaped ones. 
Maybe. 
Depending on which forum/website/YouTube video/General internet expert you listen to....   :Unsure:

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## PlatypusGardens

> Make 1, get it right then do a cutting list and have at it.

  
Funnily enough I stuffed up the first one.   :Rofl5:   
But the other 3 turned out just fine.

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## ringtail

Bwahahaha. Cool. Now you need to "option" them with a bbq plate that locks on to the top bars.

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## Marc

They look cute. You are always cooking something  :Rofl5:  
The feeding tube is vertical not at an angle ...(?) Works better?

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## Marc

So you have $4 in steel, if you do the lazy quote by multiplying by 5 your materials, you have a total cost of $20, sell at 60 sounds just right.  :Smilie:

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## ringtail

Hooray ! Found my vids. Will youtube them shortly. Takes sooooo bloody long to upload though. Maybe one at a time

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## ringtail

> So you have $4 in steel, if you do the lazy quote by multiplying by 5 your materials, you have a total cost of $20, sell at 60 sounds just right.

  
+ Cut off discs
gas
welding wire
flap discs
electricity
wear and tear
Labour 
$160 is right, $60 is marketable

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## PlatypusGardens

> They look cute. You are always cooking something

  Hehe not actually cooking anything there...just put the pot on for demonstration purposes.     

> The feeding tube is vertical not at an angle ...(?) Works better?

  Seems to work ok yes.
Also it was easier to make all the cuts 45 degrees     

> So you have $4 in steel, if you do the lazy quote by multiplying by 5 your materials, you have a total cost of $20, sell at 60 sounds just right.

   

> + Cut off discs gas welding wire flap discs electricity wear and tear Labour  $160 is right, $60 is marketable

  Yeh but you can't think like that.
I do this because I enjoy it.
And if I wasn't making these I'd be building something else.
The "shed consumables" are going to be consumed, regardless.  
Whatever cash I have in my pocket after a day at the markets is what matters.  :Wink:    
Nobody is gonna pay more than $60 for one of these.    :Smilie:

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## ringtail

Mild language warning. I have a few more before the fire door went on  https://youtu.be/AwC4iHrmgiI  https://youtu.be/jInNtrJV7mc

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## ringtail

> Hehe not actually cooking anything there...just put the pot on for demonstration purposes.     
> Seems to work ok yes.
> Also it was easier to make all the cuts 45 degrees       
> Yeh but you can't think like that.
> I do this because I enjoy it.
> And if I wasn't making these I'd be building something else.
> The "shed consumables" are going to be consumed, regardless.  
> Whatever cash I have in my pocket after a day at the markets is what matters.    
> Nobody is gonna pay more than $60 for one of these.

  Oh I totally agree. As long as you cover your material costs though all is good.

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## PlatypusGardens

> Mild language warning. I have a few more before the fire door went on  https://youtu.be/AwC4iHrmgiI  https://youtu.be/jInNtrJV7mc

  Holy Dooley alright! 
My little ones don't quite get to that stage....  
Suppose the might if I load them up...

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## ringtail

It goes well that one. I added a little door right at the bottom to empty the ash out. We used it at the farm last winter as a heater. Had the fire in front and the rocket stove behind us. Toasty. That's the one that Gabrielle Apostle wanted credit for. When totally finished it has 3 additional air inlets at the base of the flue. I'll upload that vid tomorrow

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## PlatypusGardens

I like this one.

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## ringtail

Beast

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## PlatypusGardens

More ideas  :Biggrin:

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## ringtail

I remember watching that one too. Ahhh, memories.  :Tongue:

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## PlatypusGardens

Did you try it?   :Smilie:

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## Marc

> Hehe not actually cooking anything there...just put the pot on for demonstration purposes.     
> Seems to work ok yes.
> Also it was easier to make all the cuts 45 degrees       
> Yeh but you can't think like that.
> I do this because I enjoy it.
> And if I wasn't making these I'd be building something else.
> The "shed consumables" are going to be consumed, regardless.  
> Whatever cash I have in my pocket after a day at the markets is what matters.    
> Nobody is gonna pay more than $60 for one of these.

  True, but nothing wrong with a profitable hobby. I found that multiplying the cost of materials by 5 covers all the other little things you use up in the workshop. Of course if you are building a large project this does not reflects true costs, it's only good for small stuff that tends to overlook the real price of making it.
Enjoying what you do is the key to happiness ... apparently  :Smilie:

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## ringtail

Nah, have to draw the line somewhere. I gave up on them totally after our huge brick rocket stove was flooded. It was buried in the ground and was our shower heat exchanger at the farm. When we got all that rain the ground became saturated and filled the stove up = no shower = PITA. Therefore I built a gas powered heat exchanger for the shower. Much easier and instant hot water. I did find the rocket stove took so much time just to get two showers it wasn't worth persisting with. We were spending 4 hours a day fuelling it which is not a good use of time. Different story if we lived there full time though. A much  better system could be built like the permaculture institute has - no doubt you've seen the vid for that.

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## ringtail

> True, but nothing wrong with a profitable hobby. I found that multiplying the cost of materials by 5 covers all the other little things you use up in the workshop. Of course if you are building a large project this does not reflects true costs, it's only good for small stuff that tends to overlook the real price of making it.
> Enjoying what you do is the key to happiness ... apparently

  True, apparently  :Biggrin:

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## Marc

The alternative methods of heating water tend to be time consuming and don't suit our modern lifestyle. We used to have a water pipe going through our wood fired stove and it usually clogged up with calcium residue or started leaking and we did not use the stove long enough to heat up the tank anyway. The one exception to that was a new hot water tank I bought, rather crude it was a enamel covered tank with a hole/flue in the centre just like the gas hot water systems but with a small furnace under it. You started a small fire with sticks under it and it was hot in no time.  It was common to see this contraptions boiling away when people over fuelled them. 
it would be easy enough to make one with an old gas hot water system providing it does not leak ...
You could hook it up to a secondary hot water tank and heat it up by thermal circulation.

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## InsaneAsylum

Anyone keen to fit a blower fan or similar to the air intake? I wonder how the Turbo Rocket Stove would go  :Biggrin:  
I take no responsibility for injury, death or damage to property caused by said Turbo Rocket Stove

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## PlatypusGardens

> Nah, have to draw the line somewhere. I gave up on them totally after our huge brick rocket stove was flooded. It was buried in the ground and was our shower heat exchanger at the farm. When we got all that rain the ground became saturated and filled the stove up = no shower = PITA. Therefore I built a gas powered heat exchanger for the shower. Much easier and instant hot water. I did find the rocket stove took so much time just to get two showers it wasn't worth persisting with. We were spending 4 hours a day fuelling it which is not a good use of time. Different story if we lived there full time though. A much  better system could be built like the permaculture institute has - no doubt you've seen the vid for that.

  
Fair enuff, didn't know you were using it/them for heating water.   :Smilie:

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## PlatypusGardens

> Anyone keen to fit a blower fan or similar to the air intake? I wonder how the Turbo Rocket Stove would go  
> I take no responsibility for injury, death or damage to property caused by said Turbo Rocket Stove

  
Well....given some of the vids I've seen....if you get it right, no blower needed...  
I added a little second air intake to mine, will try it later.   :Smilie:

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## PlatypusGardens

Seems to have given it more beans  :Biggrin:       
Burns almost smoke free now....but still getting a fair bit of ash/coal buildup.      :Unsure:

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## ringtail

You need less beans and more beens  :Biggrin: .

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## ringtail

> Fair enuff, didn't know you were using it/them for heating water.

  Went all hippie for a bit there. Then reality struck.  :Biggrin:

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## PlatypusGardens

> You need less beans and more beens .

  
Oops , my bad.

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## commodorenut

Hope you don't live on the same side of town as this guy:  BBQ has neighbours steaming | Mackay Daily Mercury

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## OBBob

> Hope you don't live on the same side of town as this guy:  BBQ has neighbours steaming | Mackay Daily Mercury

  
Ha ha ... have you had the 'how to be a good neighbor' pamphlet yet PG? As always, the viewer comments below are the best bit of those articles.

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## PlatypusGardens

> Hope you don't live on the same side of town as this guy:  BBQ has neighbours steaming | Mackay Daily Mercury

  
Haha well we do...sort of. 
Got it pretty good here as there's a park out the back and no houses directly nearby, part from neighbours on one side but they're ok with a bit of smoke. 
Mostly it doesn't go directly towards their house anyway.   :Smilie:

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## Uncle Bob

> Ha ha ... have you had the 'how to be a good neighbor' pamphlet yet PG? As always, the viewer comments below are the best bit of those articles.

  This definitely didn't get the pamphlet ...

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## PlatypusGardens

> Ha ha ... have you had the 'how to be a good neighbor' pamphlet yet PG? As always, the viewer comments below are the best bit of those articles.

  
Yeh haha I read through the comments. 
I don't think there is a single topic known to man that can be posted on the internet without people arguing about it    :Rofl5:

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## ringtail

The guy with the ozpig should fire it up 7 nights a week until the whingers move.

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## Marc

Agreed, that ozpig is a miniature, I bought one for my daughter, you can barely burn anything bigger than twigs. I would make an open fire with old shoes with a bit of cow manure for added flavour and get it started with diesel  :Smilie:

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## PlatypusGardens

> ozpig   
> I bought one

    :Eek:  You what!?????!?  :Eek:  
Surely you could have made one    :Roll Eyes (Sarcastic):

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## Marc

Sure could, but I needed it "today" ...  :Smilie:

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## ringtail

Your next project PG.    https://m.youtube.com/watch?v=nvlOelD5HOE 
and you can sell it to old mate ozpig  :Biggrin:

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## PlatypusGardens

> Sure could, but I needed it "today" ...

  Fair enuff.     

> Your next project PG.    https://m.youtube.com/watch?v=nvlOelD5HOE 
> and you can sell it to old mate ozpig

  Yeh seen that, pretty damn awesome.
Love how he made the whole top a cooking surface.
too clever.   
And it breaks many of the "rules" about rocket stoves as well, it seems, which is interesting.  :Wink:    
"old mate ozpig"   :Rofl5:

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## PlatypusGardens

> Your next project PG.    https://m.youtube.com/watch?v=nvlOelD5HOE

  I considered making somthing like that....for cooking....but probably not...
I'll keep tweaking the potbelly stove instead.
(added a baffle plate and another air intake up the top on that BTW, will report back on that later when I've fired it up)  
I like to see the fire. 
This whole "closing the lid and shutting the fire in" doesn't really appeal to me.
Even if it IS more economical and produces more heat/less smoke etc    :Smilie:

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## ringtail

I did look in to making a rocket stove from glass. Doable but hideous dollars involved. How awesome would it be though

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## PlatypusGardens

> I did look in to making a rocket stove from glass. Doable but hideous dollars involved. How awesome would it be though

  
That would be sweeet.

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## Marc

> I did look in to making a rocket stove from glass. Doable but hideous dollars involved. How awesome would it be though

  You can always silicone the glass together  :Smilie:

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## ringtail

What's the melting point of heat proof glass if there is such a thing ? And silicone ? Needs be at least 1500c

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## Marc

Good question but you will not like the answer. 
To start with glass is not a solid but a very dense liquid. So if you put a flat pan of glass in a round pot and come back in 2 or 300 years, the glass will be curved taking the shape of the container which is the definition of a liquid.
Well that does not help, so melting point of glass is around 1400 C and depending how much borosilicat and quartz in the mixture could go up to 1700 however that is the melting point. The glass goes soft unfortunately at about 600 C and 800 for Pyrex, so you couldn't make a rocket stove out of glass since that thing gets red hot so over 1000 C.  :Frown:  
Heat resistant glass takes a bit more heat than normal silica glass, but not that much more just 200 C more. The main quality is to resist thermal shock, that is sudden cooling or heating. Normal glass can take a differential of about 30 C, Pyrex takes 160 C 
I went to school with the son of one of the early manufacturers of Pyrex glass. Escaping Nazi Germany he established a factory abroad and started making thermos flask. His demonstration in front of an astonished audience consisted of pouring icy water in the thermos, then empty it and pour boiling oil in it. 
He must have used some trickery because boiling oil is 300 C and no Pyrex glass can resist a temperature jump of 300 C but nevertheless, he sold millions of those thermos. 
Sorry about the rocket stove.
The silicon was just a joke.

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## OBBob

Windows in 100+ year old houses are often thicker at the bottom.

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## MorganGT

> Windows in 100+ year old houses are often thicker at the bottom.

  That's because glass made that long ago was not float glass, but glass spun into a disc and flattened as it cooled, so it often appears to have 'flowed' slightly.
Glass is an amorphous solid - somewhere between a liquid and a solid, it has most of the properties of a solid but the molecules are less organised than a proper crystalline structure. Theoretically the molecules do very slowly shift towards a more stable crystalline form, but mathematical modelling suggests that at 'room temperature' the time it would take for glass to appear to have 'flowed' enough for a window to look thicker at the bottom is longer than the universe has existed.

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## PlatypusGardens

:Bbq2:               :Biggrin:

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## ringtail

Yeah baby ! Try smaller diameter sticks  :Wink:

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## PlatypusGardens

They were pretty small....  
Still getting a fair bit of coal buildup.
Might be time for a new version with ash box and offset burn tube for the vortex effect   :Biggrin:

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## PlatypusGardens

Ok. 
offset burn tube, longer flue and slightly angled feed tube   :Biggrin:     
Making everything "a bit too long" to begin with.
if it works it works otherwise I can trim a bit off.
easier than adding bits on

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## PlatypusGardens

Stuck it on an old plough disc for now while testing. 
Added some little flaps on the feed tube and down the bottom as well as a fire/ash grate.
Will see how it goes      
^ Neighbour's mutt inspecting the workmanship 
She said it's "ruff"     :Smilie:

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## ringtail

Cool. Ash removal is a key feature. If it's drawing right there should be nothing but ash, no coals. Go forth and rocket  :Biggrin:

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## PlatypusGardens

On the right track
We have a vortex   :Biggrin:    
Hard to get a decent pic

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## PlatypusGardens

Yep just emptied it out....hardly any coals, and just a tiny bit of ash.   :Smilie:   
Gonna add some bits at the top and see how it goes for cooking later. 
Migt add one of those side air intakes as well while I'm at it....

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## PlatypusGardens

:Yes:

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## ringtail

Go the vortex !

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## PlatypusGardens

Pretty cool ay?   :Cool:

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## ringtail

Indeed. Now I think we should see a fire tornado.  :Biggrin:

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## Uncle Bob

Looks great PG! Just what I want to build, just need it a little bigger.

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## PlatypusGardens

Getting more bang for my buck using the horizontal feed it seems.

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## PlatypusGardens

> Indeed. Now I think we should see a fire tornado.

  
Yes, when I started feeding it from the end rather than the chute, the flames were climbing halfway up the flue.
I'm thinking I might take 1/3 of the flue off, give it a set of legs and it should be good for cooking on.      

> Looks great PG! Just what I want to build, just need it a little bigger.

  It's getting there. 
Did you want to use yours for cooking or heating?
Or both...?    :Smilie:

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## ringtail

20 second steaks for PG

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## Uncle Bob

> Did you want to use yours for cooking or heating?
> Or both...?

  Just heating

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## ringtail

Do the full on 44 gal drum for radiant heat and thermal mass storage

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## PlatypusGardens

I like this guy's videos       
Amd that stove there seems to take some decemt size bits of timber.

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## PlatypusGardens

> Yes that's what I gather.
> Hotter flue, more burn, more heat, less smoke.....  
> ,.......right?

   

> well you be the judge of that, I only say that packing the flue with insulation of any kind will not work, not for a long time.Eventually may be but you don't want to build an oven, you want something that starts roaring straight away.

  
...about that.... 
From what I've seen and read you DO want to insulate the flue with a second skin and perlite or vermiculate but not sand.
Sand retains the heat and radiates it out while the pe/ve insulates the flue, making it keep its heat, which gives a cleaner burn. 
...which is what I want...as I want more heat at the top of the flue for cooking.    :Smilie:

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## ringtail

Those nutters ernie and erica reckon insulating the burn chamber is critical

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## PlatypusGardens

> I've been looking at building one for the place down the coast. I'd like a small footprint yet big enough to take a load other than sticks (IE; no wood spitting except kindling). Those criteria pretty much rule out most of the designs I've seen.

  
Something like this..?

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## PlatypusGardens

Maybe you don't need to insulate the whole thing.....just the lower part of the flue....       :Cool:

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## PlatypusGardens

> Those nutters ernie and erica reckon insulating the burn chamber is critical

  
Oh yea?
hmm.

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## ringtail

I like that one PG. Workshop and greenhouse heating seem to be big In the UK / USA

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## ringtail

> Oh yea?
> hmm.

  They started stuffing around with ceramic fire tubes I think

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## PlatypusGardens

> I like that one PG. Workshop and greenhouse heating seem to be big In the UK / USA

  
Sure does.
Can't say I blame them.

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## PlatypusGardens

Hmmm this looks a lot like the one I made and filled with sand.
Might have to have another look at that little setup some time

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## PlatypusGardens

Ok.....insulating the flue.  
Started with one of those little pump tanks.       
Skin off an old HWS       
Cut it down a bit, and after some struggling it was tucked inside and attached to the yellow thing   
 Ended up just pop riveting it along the vertical join.
If this works ok I'll most likely replace it with something a bit better looking and fitting.
Maybe some ducting of some sort....who knows.     
Ready for filling     
Off to the green shed for some of that purrrrmickurlate stuff.

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## ringtail

Garden section IIRC.

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## PlatypusGardens

Yeh, got a couple of bags....not enough to fill the whole thing so cut a bit of the sleeve off. 
Filled it up, lit the stove, WOOOSH!!!! Flames coming out the end of the flue for the first time ever.    
For a while.
Then it went back to being its usual difficult self again. 
Just can't seem to keep it going for any length of time.
It's so sensitive.   :Shock:  
With a handful of sticks in there, moving one single stick or twig a tiny bit can be the difference between roaring rocketing fire and the thing going out completely. 
When using the angled (almost vertical) feed tube, the difference between holding the other flap shut and opening it as little as 10mm is huge. 
I think the air intake in line with and behind the angled feed tube is a good idea to get air in behind the wood so will look at adding one of them.
 Maybe make the feed tube a bit bigger, so I can load it up and shut the lid, then all the air comes in through its own tube....  
Couldn't get it to work at all using the horizontal tube as feed tube today.  
It's close.
So close....yet so far away from just WORKING on its own without having to be fiddled with every ten seconds.   
Not sure what it is that's missing to be able to load it full of wood and it will just do its own thing, once the flue is hot enough.... 
Something being too long/short/wide/narrow/etc......? 
Might look at shortening the flue a tad and making the flaps closing shut properly with some latches.
Not for a while though, heading off on Monday for a couple of weeks holiday and this weekend will be busy.    :Smilie:

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## Marc

It will take off soon enough  :Smilie:

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## ringtail

I hear ya PG. Tricky beasts. I still think air is the key. Too much, too little, where it enters etc....Since there is no golden rule with these things it's 100% experimental.

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## PlatypusGardens

So it seems. 
Need to find me a dead tree and get some twigs off it.
No good trying to split pieces of pine down to chopstick size   :Shock:     
I did a good job at sharpening that axe though....clean cut straight through the nail   :Unsure:  Eek

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## PlatypusGardens

Cut a hole for air intake with plasma cutter.
very handy for stuff like that.       
And a latch on the front flap to keep it shut        
Now to go hunting for some dry twigs.

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## PlatypusGardens

Still hit and miss but the lower 1/3 of the flue got red hot..... 
...which it didn't before.....

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## PlatypusGardens

Another observation    
Looking down the flue, ther's a distinct line right at the level where the insulation finishes.
The top part is a lot more sooty. 
I did  notice there was a lot more smoke this time around towards the end.
Wonder if that was from the pipe "burning off" as it heated up more than before. 
hmm

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## Marc

Red hot is good!
red finger... No good  :Annoyed:

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## Marc

Should add a forge blower to the air intake :Smilie:

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