Seeking plans for oil drum rocket (for trailer sauna)

Greetings.

I have a sauna trailer built, now need to figure out what kind of stove to put in it. Would like it to be as efficient-burning as possible, hence looking into rocket designs.

I've seen photos of the Minnie Mouse and Cottage Rocket, which seem like they might be appropriate. So far haven't managed to find much about how they're built, as in dimensions and so on.

A water heating option would also be good, as would something that doesn't need very frequent loading, if that's even possible with such a design.

Have searched through here for 'sauna rocket' but haven't found much that's relevant.

Sent an email to Uncle Mud, though as yet no response. So posting here in the hope that someone might be able to advise.

Cheers.

Edit: after posting this, I was shown this thread (which somehow didn't come up on the search I did), where there's a few pictures of the Cottage Rocket.
https://permies.com/t/220/157417/permaculture-projects/Kyle-Permie-Bootcamp-BRK#1286537

More Cottage Rocket:

https://unclemud.com/projects/cottage-rocket

https://youtu.be/aJNgWMyM5_g?t=212

Hi Adam;
Let me start with your hope for water heating.  It can be done with a mass heater but, other than a kettle on top it should not be attempted with a rocket stove.
The extreme heat generated by a rocket at full burn will flash water to steam in a moment.  You do not want to be inside a sauna room if your water heater goes to steam and bursts suddenly into the room.

Now let's move on to less wood loading.  
You can build a batchbox RMH and extend load time but my question is why?
A J tube rocket can run you out of a room with how hot they get.
A J tube will roar like a dragon while burning.(very enjoyable)
An 8" J tube will burn 45 minutes or more with no wood added.
Sitting next to an open J tube casually poking it and occasionally adding a stick of wood is one of life's great joys!  In my opinion anyway!

Have you ever built a rocket stove?
Get some clay bricks and a bucket of clay mud.
Write back when you have them and we will give you the proper dimensions to build one out in your yard.
Play with it , cook with it and after you are hooked then build one in your sauna.

Hello Thomas,

Thank you for the quick response.

Yes, I have cooked on simple rockets, as well as TLUDs, and even had a RMH in my house. But never worked with an oil drum type construction. Hence my questions about the different designs I've seen of those.

Point taken regarding water, though for sauna/washing purposes I wonder if there's a way of gently heating some, without anything being under pressure.

And with the loading, yeah, probably not an issue, but as I say I've never experienced an oil drum design, so don't have much of an idea of how long it'd take to heat up the space.

Don't currently have a yard to play in, but do have a builder friend wanting to help and let me do that at his place, where my trailer is parked up. Just need a bit more of a clue for what parts to procure, and how to put them together.

Any thoughts on pros/cons of the 2 designs I mentioned?

Hi Adam;
Uncle mud's cottage rocket is a proven design. I have seen one in person but not lit at the Wheaton ranch.
It is a good-looking unit that will no doubt perform great in a sauna.
I cannot help you with the building details.  
I see you have already located the permies links showing partial build pictures that I was going to show you.
I would think that Chris (mud) would be selling the build plans on his website.
He is a busy guy and the emails I have sent him in the past have taken up to a week or more before he has time to respond.
Hang in there he will get back to you eventually.
Now Peters mini mouse I did not get to see in person.
I'm sure there are plenty of videos in Paul's collection that shows Peter constructing it.
As far as build plans for it, I'm not sure.
As an innovator, Peter knows what he wants and builds it.
Quite a few of his builds are one-of-a-kind built on the spot.

The gentle heating of water is best done with an open-top container.
A simple pot with a dipper on top of your barrel or a smaller barrel  5-16 gal suspended over the rocket with a hose bib and hose to bring warmed water down to use.

OK, will hang on in there.

I looked at the photos another time and seems that with these 6 one can more or less get the idea.

I was thinking it'd be good to put mesh holding rocks on top of the barrel, in which case I guess I might have to choose between that and heating the water on there.

Any idea how much these barrel tops can take before they burn out? Worth reinforcing with something from the inside perhaps?

Looks great Adam!
The barrel will last for quite a long time. People here have used their RMH barrels for 10+ years and are in still very good condition.
I think it’s the very low oxygen in the barrel that keeps the metal from spalling.
May you have many happy sauna sessions with your new stove.

Hi Adam!

As part of the Earth friendly heat KickStarter I’m developing 3d models and plans for some of the builds including the cottage rocket at the sauna. They will be done real soon and I’ll link to them once their up here at permies :) The movie also has a section that talks specifically about this design.

Thanks, Gerry.

Andrès: I see that the cottage rocket on your link looks a little different from the one I've shown. Perhaps the difference is the hopper. So the plans going to be for people who already purchased the videos? Any more specific time estimate for when they'll likely be ready?

I'm also wondering why there's no rocks in the design. I guess that I would put a mesh to contain them on the top of the barrel.

What is the riser made out of?  I'm hoping to build the cottage rocket for a workshop next spring.  Don't need the mass, need fast heat quickly.

Here you can find plans for the cottage rocket:  https://permies.com/t/193729/Plans-Cottage-Style-Sauna-Rocket