Has anyone worked with codes for RMH in Delaware County NY

Thomas!
Thank you for the kind words, I would love to build these thingys for a living. Designing and material sourcing was very tedious but the build has been exciting! I do feel it's going quite well, I guess we'll see once she's fired up!

One thing that just occurred to me. I didn't use fireclay to seal riser onto the core, nor to extend the feed tube. I have been using the natural clay almost exclusively, do to how well in held up in cob experiments. Should I go in and replace with fireclay while those areas are still accessible?

As long as you used plenty of sand with the clay it will be fine!
Congratulations on becoming a rocket scientist!
Bet ya didn't know we snuck up behind and got your picture :-)

First firings!
I am midway through my third firing. Each time has started up no problem and with no smoke. Things are getting warm but probably not as warm they could be. I just got the infrared thermometer today so here’s what I’m getting: Barrel top hasn’t gotten hotter than 350 F, barrel sides are around 250. Bench closest to the manifold I got to 160, and going down to 110 at then end of the bench. Exhaust is around 105 F. I am very happy with the start ups and even without the mass the space is warming up. But I’d like to push it hotter if possible. There is a 3” top gap above the riser, maybe I’ll bring it to 2”. But any other thought and suggestions I’d love to hear. I know things can change once every  thing has dry mass on it! Or if you have any firebuilding tips for a hotter fire?

Also, I am wondering if anyone has advice for mixing cob with wet clay. I had been making slip with dry clay but all my clay is soggy from the snow. I’d like to get the majority of the mass on this week!

Thanks! as always!

Hoooray! Sophie.

Glad to hear your dragon is chugging along and in the right direction!

Be careful how low you take your barrel over the heat riser. 2" is bare minimum and can cause a lot of drag especially when it starts to accumulate a bit of ash on the top of the riser.
To get a hotter fire, one trick is to split your wood even smaller than what you are burning in your photo. Loosely pack as much as you can in there which will create a lot more surface area and more flame. Of course it will burn away much quicker, but that's the trade-off.

I'm not sure of your question with making cob with wet clay. Are you concerned about proportions being off with the extra water?
Cob is not an exact science and varies according to your materials but mostly you end up going by feel after a while. Its quite forgiving stuff.
Wet cob may be easier to mix and apply but also increases the drying time however, too dry and it can be too crumbly to work with and not stick very well.
The first layer is not super important to get it right but does teach you what can be done to improve it with the next layer.

Thanks Gary!
I tried your trick and yup that brought the temps right up. After 2 hours of burning like that I have the barrel top at 520, side at 355. From of barrel past 200 and the end at 130. The exhaust is around 120. I sure blew through some wood but  Feeling pretty satisfied with these numbers. I guess I won’t raise the riser any. Thanks for that!

You know how once clay is damp it becomes very difficult for it to dissolve into water? That is what I meant by that. Mix it as is it is very difficult to disperse it evenly into the sand. Right now I’m cooking the clay in the top of the barrel and drying some in the sun!

I started a layer of cob into the masonry. I imagine it doesn’t need too many inches, the heat barely gets through the brick. Once I have more slip I’ll be starting on the mass!

Sophie Gell wrote:You know how once clay is damp it becomes very difficult for it to dissolve into water? That is what I meant by that. Mix it as is it is very difficult to disperse it evenly into the sand. Right now I’m cooking the clay in the top of the barrel and drying some in the sun!

I use a drywall paddle mixer attached to a drill  (not one of those cheap paint mixers that break real easy) to mix up my wet clay. I break it up into chunks, throw it into a bucket then pour a fair amount of water in until I can mix it until the consistency of a very thick milkshake - much thicker than clay slip. If you have some time, letting the clay chunks soak overnight helps a lot to make it much easier to blend without splashing clay slip everywhere from the chunks rolling around.

Glad to hear you got some good temps. The small sticks that get things going real good can be mixed with some bigger pieces to help balance heat with longevity.

Hello!
It has been a couple months but just wanted to pop in with some updates.
My RMH has been doing a great job keeping me warm through this cold winter, though I am excited for the temps to go up and to give it a nice long vacation.
Overall its been great, I'd say that it does use a bit more wood than I'd expected to need prior to completion, still significantly less than the wood stove, although definitely more processing labor required. On the days that I work i generally start burning it around 6pm to 10 pm (with the door closed) when I go to bed. In the morning I am cold, but my room is still significantly warmer than the other rooms in the building. All that being said, it has been below freezing for around 2 months now, and it operates in a traditionally built semi large, one floor building with lots of windows, but no passive solar, and no other forms of heat. For the most part, I am warm, so I'm happy.

Now that spring is growing near, I am starting to think about a final coat for the heater. My top coat now is just a pretty smooth careful layer of cob. There is plenty of dust and sand to sweep up one the regular, and any water drip or spill is a bit traumatizing. Some tiles are lifting out, and some of the sharper corners have little chunks missing.

I guess the 3 options are clay plaster, lime plaster, and or linseed oil?

Looking into lime but I am concerned about the freshness of Type S Lime (what appears to be available), and concerned that I won't have much luck getting a fresh batch due to covid and all.
Clay plaster seems more simple but I will need to collect some very specific materials. (Manure, cattail fluff, very fine sand). And will the clay plaster protect the cob from occasional water damage?

I guess the third option would be another thin (corrective) coat of cob and then linseed oil.

Curious on your thoughts! Hope everyone has been safe and well.

Curious if anyone has any reccomendations,

Thanks for the update Sophie!  Always nice to see how builds are performing and holding up.

The chalky, sandy nature of untreated cob will almost never go away unless you seal it up as you've found out. What has worked really well for me is adding some wheat paste to my final coat of plaster which eliminates the dusting and also helps to hold things together, giving the mix a dough like consistency.

Linseed oil has worked great for me too. 2-3 coats has produced a hard surface that has seen a lot of banging for wood being chopped close to my bench with only minor denting.

You may want to look into something called tadelakt which is another method of waterproofing a surface with plaster.

Hi Gary!
Thanks. When you say your final coat of plaster, do you mean your final coat of cob? So same mix as the rest, but with the addition of wheat paste? and may I ask what ratio you would use with that. Thinking maybe this plus linseed is the simplest option.

Yes, you could call it the final coat of cob if you want Sophie. To me cob is a more coarse material that makes up the bulk of a structure and plaster as being a much more refined product that is a thin layer over the cob to give it a nice look and help protect the cob underneath from wear & moisture.

I mostly went by feel when adding the wheat paste. My ratio was 3 fine sifted sand : 1 sifted clay : handful of cattail fluff and/or short straw to about maybe 1/2 wheat paste.

I did a few test samples on my bench until I was happy with a recipe. To some, I added some cement colourant which gave it a really nice tone.

If you search for "Earthen plaster recipe" on the internet, you'll get lots of varied recipes and great information.

BTW...Gary is my secret undercover name nobody is supposed to know. We'll keep that between us OK?

I also live in Delaware County NY.  Hi Neighbor.  would love to chat about your homestead.  nancyl@hancock.net

Did you finish this project? I am also curious, I am very close by in Narrowsburg, NY.

Hi Nancy and Trevor!
Sorry for the delay but cool to hear there are interested neighbors. I did finish and ran it all this past winter. Still need to get to the finishing coat though.

Quick update!

Finally got a finish coat on after a year and I am very pleased!
The finish is extremely hard, even the areas that remained somewhat rough do not break or dust off.
And I'm having pretty much zero dusting.

After the plaster went on I did 3 coats of linseed oil. You can see that the oil was not absorbed evenly resulting in some discoloration. I suppose I could apply another coat to the areas that remained light but I don't want to smell it right now.

Recipe I used:

3- Fine mason sand
1 - Equal parts clay slip- horse manure
1/4 c boiled linseed
1/4 c powdered milk
handful cattail fluff
I added some ochre pigment too

In one of the before pics you can see serious water damage done to the pure cob my previously leaking chimney. Well now the chimney is fixed and I even spilled a cup of tea on the surface of the heater- it stayed as puddles and was not absorbed by the plaster. My mind is blown. Yippee

Oh! I did make the mistake of leaving the linseed oil to cure on the tiles in between coats. I did not know it would gunk up like that. Scrubbing each and every tile with mineral oil was a pain- now I know!