Vortex Stove

[fishalive12345]

I've been reading about this stuff for several years but it's only now that I have to make decisions that I'm starting to understand so many important points. The difference between 4-5-6" hadn't really registered with me until now. Or how the system needs to fit your house, your climate, your cooking requirements and how much time you spend at home.
I'm going to try building a 120 or 130mm system which correspond to a 5" system. Reading about sizing on the Uzume site (in French only) which is the best explanation I've seen, 5" is too small for the coldest possible scenario for our house in our location but the calculations don't take cooking needs into consideration i.e that you might need or want to cook or bake on the stove even when it's warm out.

Anyways, thanks for your replies. I'm going to try out a 5" combustion system outside and see what happens while starting up a thread to ask for advice about the heat recovery system. Not really sure where to start it as I see yours is in 'Other types of stove' whereas the double shoebox and Matt Walker stoves are in another section.

[Vortex]

I think a 5" would be a better choice for you, a 5" system would probably be adequate for my house the majority of the time.
I originally put the thread in the 'Other types of stoves' section as at the time it wasn't clear whether it would be classed as a rocket stove, now with the Aryan afterburner it definitely is. Sounds like your thread would probably be best in the 'Heat storage/distribution' section.

[patamos]

And in case it has not already been mentioned: You can always fire a smaller heater more often or do multiple reloads.
For cooking purposes it is nice to size the fire chamber smaller, and arrange the longer flywheel harvest to absorb twice daily firings... etc...

[fishalive12345]

That's the direction I've found myself going in so it's good to get confirmation from people with experience that it's the right direction . Thanks.

[Bram]

Dec 4, 2017 5:55:15 GMT -8 Vortex said:

Hotplates are finally finished. I didn't fancy cutting the 10mm plate myself so I spent half a day driving to the nearest engineers shop and got them cut, only to get home and discover they were both 10mm out of square... So ended up having to cut them myself anyway.



Lift out grate. (it's 5mm smaller than the hole so it doesn't expand and break the cast).

Copper sheet in place and firebox door frame pieces sat in position awaiting welding.

Hi there Vortex,

I followed your advice from my WRC thread and came here. As I understand it the top plate you see in the first picture is lying upside down. You have one 10mm top plate that slides in between the thick flat irons that sit  on top of the bricks (also 10mm steel). Then on top of all of that is welded a 5mm piece of steel that covers all of  this?

[Bram]

When I look at the left top plate in the second picture I believe I can see the discoloration of the weld. Is that the 10mm steel plate?

[Vortex]

Hi Bram, Yes that top picture shows the left-hand hotplate upside down. These 2 pictures show it clearer. There is a 10mm thick 100mm wide steel frame that sits on top of the bricks, the angle steel pieces bolt around the edges, and the hotplates sit inside of that:





You can see the weld through the 5mm steel top but it creates quite a nice effect.

[Bram]

Cheers Vortex,

this will probably be how I do it a next time. For now we are going with a cast iron plate. Your build is really inspiring!

[cork]

`Hi Trev ,
I was wondering if you found a solution for putting a cowl on your chimney. If I remember correctly the stove did not operate well with one, maybe readjusting the plate in the afterburner might help?

[Vortex]

Hi, (James?)
Recently when giving the stove it's yearly cleanout I discovered more water damage where rain's been getting blown under the chimney cowl and running down the pipe into the stove. It wouldn't happen most places but here on the Atlantic coast the rain is often horizontal. It took some work to sort out and I didn't want it happening again so I spent a wet day researching chimney cowls. Looked at dozens of different types and read hundreds of reviews. The anti-down draft cowls looked the best, but they all seemed to either fail at keeping the rain out or slowed the draw down too much. Apart from that the new ones are all made of 0.4mm / 0.015 inch stainless steel. It's so thin the wind here would tear it to shreds in no time. I ended up buying a vintage one from the U.K. It's made from 1mm stove enameled steel, and looks like it has enough clearance around the pipe opening to avoid any restriction. It hasn't arrived yet, I'll let you know how it works out.

[cork]

Hi Trev,
Yes it is James. In getting the chimney ready for the stove I discovered a lot water ingression through cracked flaunching which of course did some damage consequently I'm anxious to keep it out in the future.The cottage is on a plateau but nowhere near as exposed as your place. I had thought to put a cowl on and adjust (tune) the stove then. Have only casted the bits for firebox this week so its early days. Thanks for all your help.

[Vortex]

Hi James, Great to hear you've made a start on building your stove.

I've adjusted the top gap in the afterburner back from 3" to 3-3/4" to see if that would stop the etching of the glass. Haven't had a chance to try it out yet as the weather is still so mild. I don't know if you could tune the stove to a tight chimney cowl that way, my instinct says no.

This type of cowl was my second choice: www.fluedirect.co.uk/31-200-091-anti-wind-cowl-200mm.html I was going to get the 200mm / 8" one even though I have a 150mm / 6" chimney as that would have a lot less restriction and would fit on the outside of the insulated chimney pipe.

[cork]

I'm afraid the liner and cowl was already ordered,however exit cross sectional area of cowl is 183% of system size so hoping this is enough. Salesman said I could return it if necessary. Another question, does the metal on outside of stove require much maintenance to stop it tarnishing?
The cowl is a regular umbrella type rain cowl.

[Vortex]

I'm sure 183% CSA around the cowl will be fine, especially where you are. I've been using a basic old 8" stainless Umbrella cowl while I work on the new one, so far it's kept the rain out OK, but I have had a few blow-backs in the windy weather. The new one was more restricted than it looked in the pictures so I've made some improvements to it, hope to get it on the roof tomorrow.

The outside metal on the stove requires very little maintenance so long as you don't let it get wet and leave it, it rusts surprisingly fast which you can clean off but leaves the surface pitted. I tried various different coatings on the old stove, best I found was a light spray of the black high temp exhaust manifold paint (done outside as it stinks) once it's dry I go over it with some Zebrite stove black. To clean it I use a very light spray of WD40 and polish it off with a rag.

[graham]

Very nice. But is there still room for the cat to sleep on?