First thing, we need a big ol' bath tub to have our spa bath in. We chose a spot right by the gazeebo that is near my tent, and started digging a hole. Next was to make a frame to hold the tub and also create a deck around it that joined up to the gazeebo. I may have mentioned before, but it was interesting building a structure on non-level ground. Something I had never thought of before was to drive big posts into the ground (or even auger out holes to put in even bigger posts) and then attach the main supports to these posts so that it is all level. Then we added joysts between the inner and outer frame which gave us a complete frame to put the decking wood onto. Below is a picture of the tub and deck all completed (minus the bench seats that Nico and I added on later).
The next part of this spa bath is to have some way to hold and heat up a whole lot of hot water. Here, there is an unexhaustable source of firewood, so we made a fire pit! We also got a 1600 Liter vat to hold the water. I learned a whole lot about concreting and brick laying in this part. A hole was dug into the side of a little hill to make a flat area to have the firepit. We mixed and poured concrete into the bottom to make a level ground to build the walls up from. We then built walls on three sides to support the huge vat, and added a concrete pipe as a chimney in the back. And vuallah! a cheap way to heat tons of water.
Since we've been a bit short on rain (and hence water at the house) we filled up a tank of water from the river on the land and pumped it into the vat. It took about an hour and a half of having a fire in the new pit to get the water up to about 140 degrees F. Then with the gravity feed and the 50mm (2") piping, it took only about 3 minutes to fill almost the whole tub! We even had to mix in some cold water cause it was too hot!
Then finally, enjoy :)
I've got some more pictures of the whole building process up on my picasa site: http://picasaweb.google.com/dave.dayan/SpaBath#