Re-think; reboot; recycle...now it gets real.

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Re-think; reboot; recycle...now it gets real.

Postby smallhagrid » Mon Dec 30, 2013 2:36 am

So...after (too many) false starts the actual build is now in place and really - seriously - commitedly in progress.

I looked at the same stuff over and over and finally a useful pattern emerged...:

This needed to be off the floor=> hence the old cast iron stove base which I'd already leveled with assorted bits & bobs.

The base needed expanding to be usable so on top of that went the funky 7-sided kiln ends.

Stubborn old me wanted both vertical and horizontal access at the 'front' to the burn tube so that got made from some old, thick stovepipes with an elbow for connecting the riser and a hand-made tee for the vertical burn tube opening.
Both entrances can be capped with a standard stovepipe cap too - so I can cap whichever one needs it - or get a 2nd cap to cap both when it is not in use or if it needs to be snuffed out in a hurry for some reason.

True strangeness starts here=>
The stovepipe parts will naturally be of limited life so they are being used as a mold and under the burn tunnel there is a funky slab of cast iron that was one side of the old box stove that I junked for parts.
That slab boosts up the burn tunnel so the horizontal cap works really well and it also serves as the bottom outside of my 'mold'.

Once all this got started serendipity took over and a great guy at a local business gave me a wonderful ring-type 55 gallon barrel & lid - and that lid forms the base where the barrel will sit so I get the dimensions right (it is also slid under the cast iron slab which makes a slight upward angle for the burn tunnel).

Around the perimeter of the barrel lid I cobbled together a funky ring of angled kiln firebricks and 1/2's of regular firebricks with the exit tube embedded between those bricks.
(Thus far I've not had to use a single one of the really good firebricks as all I've used came from the old kiln & some 1/2's that the potter gave me so I've not even cut a single brick yet.)

This is all placed so as to create as large an exit path as I could arrange and there will be at least 2 courses of firebricks all globbed together with mortar for strength & sealing.

The easiest way I could imagine to form the burn tunnel's thickness was by making a starting layer of mortar + perlite mix - that was done & allowed to set overnight.

Next the rocket tube was made by cutting an opening to form around the 6" burn tube and mating tightly at the bottom and with the bricks so as to keep the perlite in as well as possible; it was then filled between the 6" & 8" pipes with perlite, but not finished at the top because there will be a needed height adjustment for the proper clearance to the barrel end.

Comment about this process=>
Making an insulated pipe with perlite is really quite fun & I highly recommend it !!!

Then I added one side + top of the burn tunnel's body using a board for a form secured by screws & string while I filled it in by hand with mortar for the thicker outer, strong layer to hold it all together.

One thing I am very glad of is that I remembered that when folks didn't have lots of fancy stuff to form things with - they just cobbled them together using what they had to hand with a good mason's trowel - and mortar formed this way, good & wet gets very solid & strong after it sets - and that is what I am doing here.

Yes - I do have some pictures already - but just typing this out is all I'm good for tonight and if all goes well I'll post a bunch after the next phase of building is setting.

Tomorrow, when there is daylight I'll snap some more shots of it's interim state before I move the form board to make the other side/top part - I also plan to add the 2nd course of the 'ring' part.

I will try to get shots before/after each phase to share with the good folks here.

My only wee concern is that I may have made the burn tunnel too long - and once it is cast in, well=> that, as they say is that.
On the flip side of that possible boo-boo though there will be a very big & free-flowing space at the other end so I ain't worrying too much about it becoming a problem, really.

Also I am adhering to my firm belief that this needn't be overly scientific to be quite good & usable.
I got really 'burned out' with all the hoity-toity technicalities I saw cited over at other places - so I am following Kevin Bacon's suggestions that these things can be cobbled together very simply without being too fussy about all of it.

My goals also remain unchanged - I want it to be safe - to make heat where heat is needed - use little fuel - and in the best of all worlds have a really nice, low outlet temperature.

And finally - after it is all made, set & well tested I may also jacket the burn tunnel with some metal that I have.
I am also considering using those really good firebricks as a non-fastened thermal mass along the wet wall beside the new heater - but this is all yet to be determined as trials & observations are made.

All this still depends upon what sort of outlet temp it ends up making - if it is cool enough I still plan to use the flex tubing but if it needs more heat to go away before that I'll bite the bullet and buy some more stovepipe stuff.

This design has allowed me to use up all the goodies I had on hand which pleases me greatly.
So far all I've bought this week are an elbow, a cap and a 2nd bag of mortar.

This critter will have built-in mass aplenty once I'm done swaddling it in mortar and stuff...
It must already (easily) weigh 300 pounds or more between the full (60#) bag of mortar, bricks & cast iron parts - and no matter what I'll also shoe-horn in at least the 2nd (80#) bag of mortar - and that barrel ain't light either.

I'll be getting impatient waiting to see how this will work while it all sets, that's for sure.

Best Wishes to All !!!
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Re: Re-think; reboot; recycle...now it gets real.

Postby pa_friendly_guy » Mon Dec 30, 2013 5:21 am

Congrats, I for 1 am glad that you bit the bullet and started to cast your stove. I know it was a huge step for you, but nothing ventured, nothing gained. :) Let us know how it works out for you, I am sure that we are all pulling for you. :D
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Re: Re-think; reboot; recycle...now it gets real.

Postby colin saengdara » Mon Dec 30, 2013 7:56 pm

Congratulation Hagrid! I know you've given this a lot of thought, which is great because this stove will have a personality, and all your research and hard work will guide you to truly understanding it.

Here's to hoping that it satisfies!
-Colin
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Re: Re-think; reboot; recycle...now it gets real.

Postby smallhagrid » Mon Dec 30, 2013 8:37 pm

Thanks Colin & Pa_friendly_guy.
One thing is certain, I'll have my fill of playing in the dirt for some time to come after this !!!

There's so much wet mortar now in that cold room that I put a small electric heater under it.

Time for a snack - some horse chores - then more playing with dirt.

Best Wishes to All !!!
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Re: Re-think; reboot; recycle...now it gets real.

Postby smallhagrid » Tue Jan 07, 2014 1:55 am

Well - it's all made & the mess is even cleaned up now !!
(Just waiting for the last mortar to set...)

Ultimately this RMH got made in the finest spirit of a cobbled-together fireplace - all odd bits and plentiful mortar.

Most of the bricks looked like this=>
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Because of the smallness of the room it is not possible to get good, full pics so please bear with me as I share what I could actually get - they are in progression from loose parts to fully mortared whole.

If you examine the pics of the un-mortared bottom, the barrel lid I used as a guide & support is visible in little spots.
Once the colour of it is noticed it is also clearly visible as the 'floor' of the exit chamber.
It was a huge help in making the round portion the correct size & shape.

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It's not easy to see in a photo - but the exit cavity is about a foot deep=>
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Post testing...yes, it rockets quite nicely, and the exhaust is cool enough to run through flex tubing.
The only part I am uncertain how I'll deal with is just how much water condenses in the tubing.

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My test runs were made with just potter's clay sealing the barrel down and it worked very well.
Once it had dried & cracked it was quite easy to pry off too.
Then it was time to put the barrel back on & finalize it...

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My burn tests were made on a sub-zero day here in Vermont - and that room was closed off from the heated parts of this apartment.
The total amount of stuff burned might have been a couple of pounds of wood & paper.
It warmed the room up nicely - and what really pleased me was that hours after the fire was out it kept that room nice & warm via stored heat.
There is no added bell or bench (as is obvious...), so I say if this works so well as it is - it may not need anything added.

And now - as soon as my car is fixed I'm thinking to get some lightweight pipes and make a U-tube against the wall before exhausting it via flex tubing.
I already made & set in a funky window thingy for that & it works well too.

This meets my goals quite well - it is off the old wood floor - is efficient enough to have a low outlet temp - and will safely heat the part of the house that needs it the most.

I'll try and get some final pics posted after it is all 100% done & in use...

Best Wishes to All !!!
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Re: Re-think; reboot; recycle...now it gets real.

Postby matt walker » Tue Jan 07, 2014 4:05 am

Hagrid, I'm so glad to see you making progress. Don't worry too much about the moisture in the exhaust at this point, it should dry out after a few burns. If I may make a suggestion; I strongly recommend you take that barrel outdoors and burn off that paint with a torch or bonfire or something. The smoke as that burns off is really nasty stuff. Very cool that you are moving forward, be safe and warm!
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Re: Re-think; reboot; recycle...now it gets real.

Postby mannytheseacow » Tue Jan 07, 2014 4:09 am

Sweet!!! Right on, Hagrid! I'm so glad you followed through and got that thing put together. Watch that flexible tubing- I'm curious to see how it does.

Now that you're firing you have all the time in the world for tweaking and making improvements. But the sweet thing about these things is that they work even if you don't tweak them right away. Either way, you're keeping warm with an efficient heat source!

I really like how you incorporated the old kiln and recycled bricks into the build too. That thing is awesome! Keep us posted on its performance!
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Re: Re-think; reboot; recycle...now it gets real.

Postby pa_friendly_guy » Tue Jan 07, 2014 3:20 pm

Good Job Hagrid. It looks great. When I saw the pictures I too picked up on your barrel and the fact that it has not been burned off. Matts suggestion was a good one, you don't want those fumes in the house if you can help it. You might want to think about some insulation or mass around those flex tubes, just for fire safety. It shouldn't cause you problems in the short run, they may become a problem with time. I liked the use of the recycled kiln, bricks etc. Its great to reuse things and make them of value again. Reduce, Reuse, Recycle, :D In that order, ;)
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I have a secret...!

Postby smallhagrid » Tue Jan 07, 2014 3:38 pm

Hi Matt, Manny & Pa_friendly_guy.
Thanks for your kind thoughts and suggestions.

Right here there is a huge problem with any outside burning because of something that happened in this town very near here in the past - and despite years passing the neighbors are still overly twitchy, with massive trouble resulting if they see anybody open-burning outdoors.

SO=>
Left with too few choices, I used a 'top secret' method to keep the paint fumes at bay...
Had the window wide open in that room on a 15 degree day, the room closed off from the rest of the house, and it's 2nd door open allowing ample fresh air in from the stairway.
It warmed up the incoming, upflowing air while the cool outside air sucked it right out.
This had the very desirable effect of creating a 'pump' to get the fumes out the window while the top's paint burned off.

We'll see how it goes from here paint-wise, but I'm thinking the rest will either stay put or very slowly blacken over time.

I seriously think that this is not your standard barrel paint job as it's a food-grade barrel that was used for acidic, concentrated juice - that paint is more like porcelain than any other barrel I've seen before.

The heat it's seen so far didn't even bother it anyplace except right over the rocket tube.

If it does tend to get fumey though I have the means at hand to deal with it safely indoors if need be.

Aside of that - still waiting to get my car fixed so I can get to HD for the pipe bits I want for this.
So at most it's likely to see some small burns between now & friday when it's 'sposed to "warm up" to near freezing around here...

Thanks Folks, and Best Wishes to All !!!
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