Smoke sauna generates somehow different steam. Some say, that it´s much, much better than steam from electric furnace, or even wood heated sauna with chimney. This instructable will show you how to make a mobile fireplace in order to avoid messing with hot coals and smoke and at the same time enjoy benefits of good steam.
For this project I used only recycled or found metal and field stones. If your´e more hipster than dumpsterdiver, it´s easy to buy all theese brand new shiny tubes and rust free tin-plate, but that´s really not necessary. Same goes with stones. You can buy expensive lava rock, or black diabase, but realy there is not so much difference. Some field stones will crack after months in use. if so, just throw them away and go pick another ones. Also you´ll need some sort of welding equipment, angle grinder, drilling machine, hammer and metal cuting scissors.
There will be a lot of welding, so take appropriate precausions in order to avoid any fire in the work area. Ok, let´s start.
Step 1: Place for the Rocks
Well, actually there will be no blueprint for this project. You should improvise as I did. If your sauna will fit 4-8 persons, than the basement of fireplace should be about 50x50cm. Just make some basic measurements and later cut and grind every part to fit the size. There is no need for perfect angles and sizes, just watch for basic form and usability. Note the open ended pipes on the top. Those will be used for temporary handles insertion, so weld them parralel to the wheels track.
Step 2: Wheels for the Hills
Use whatever you have on hands, but remember, they will be heated by fire, so no ballbearings, no grease, no plastic or ruber. And don´t forget to reinforce them. Weld aditional spokes, plates, or whatever you think is good for safety. If you fail, you´ll have problems not with stones, but with bloody HOT stones, so pay attention and take your time. You should locate wheels out of the center of gravity, so that the fireplace will stay stable on two wheels and supporting pole.
Step 3: Stone Puzzle
It´s time to play a stone age puzzle game and nicely arrange all theese field stones in to the fireplace. There should be no chance for any single stone to escape from fireplace, so be smart and do it in a right way (I´m not saying that there is only one right way).
Insert and adjust pipes for handles. On the rear ends of handles drill a holes and insert bolts, washers and nuts Measure and drill the holes in the front part of the handles. We´ll insert nails there, so the handles can´t slide out. After moving fireplace to sauna area, we´ll rotate the handles and nails will fall out, then we´ll push handles and take them out from other side.
Now climb on the fireplace and jump a couple of times. It should firmly hold everything together. No lumping, no screeping, no wobling. Otherwise, grab your welder again. Now take the handles and give this thing a nice shake. Roll the fireplace around (you don´t have to screem while doing this) for a while and watch for falling stones. If so, go and take stone age puzzle player courses and try it again.
Step 4: Origami
This part was somehow complicated, because I had to improvise in all theese tin-plate works. Mainly measure, cut, measure, cut, measure, cut and so on, till you get what you want. The purpose of this covering is to help to retain more heat in the fireplace, protect from the cooling wind, and to create some sort of draft, so the fire goes up to the stones. All this origami art should be easily removed when hot, so it could be quiet a shaky structure with some cracks. The thing is hold in place mainly by 10x10cm chimney. When you take out the chimney, all four sides literally fall appart. That´s how it should be, otherwise you´ll have to somehow handle red hot tin-plate.
Step 5: So What?
So now it´s time for fun part. Mainly it looks like this. You assemble the whole thing in a safe disstance and burn the big fire for 2-3 hours. After that you take down the covering and pour some water on the stones. This will remove residing ashes. Then insert and fix handles and roll the fireplace to your sauna. My sauna is some sort of felt chamber or tipi hanged to the roof of lean-to. You take out handles and leave the fireplace there for a 10-15 minutes to warm up the space. I also install tin-plate screen between fireplace and felt walls. Now it´s time to take your clothes down (and I mean ALL clothes, even if your are in the mixed gender company, or with kids), sit down, pour some water on the stones and relaxsssss...