Thursday, January 29, 2015

Tanganyika boiler

Tanzania as you know is the union of Tanganyika (mainland) and Zanzibar.  Before 1964 we were Tanganyika.  For 100 years some people have been heating their hot water with a "Tanganyika boiler".  It usually consisted of a 200 litre (55gal) barrel on its side surrounded by masonry with an opening at one end and a chimney on the other and firewood was put in and water heated several times a day.

I have used one for the 30 years living in this house, but was never happy about the efficiency as firewood became more scarce and expensive.

After learning about rocket stoves i wanted to incorporate a rocket stove.  I put it at one end and the rocket flue ends just under the water tank,  the hot are continues along the bottom of the tank and out a chimney on the other end.

As you can see it is very good flame.  throw chippings in even after it is going and you see smoke coming off the chippings but not coming out the chimney, just hot gases.  It is not perfect yet.

Would also be nice to have an oven under the horizontal chimney for baking.

I tried a metal grate but if disentegrated, so i stood facing bricks on their side spaced 2 cm apart and that works, lets see how they last.  the rocket is made with my 3cm rough tiles, then surrounded by a clay sawdust mixture for insulation, stopping the mass from being a heat sink.

Wednesday, January 21, 2015

Stone wall versus cement block

Traditionally most Urban houses have some sort of fence around the property.  Most common is Kaiapple fence, a tenacious long thorn with some edible but sour fruits.  Next common is cinder block walls and chainlink.  I opted for Kaiapple thorns many years ago but I am not so happy with them as they need to be cut several times a year, they pop inflated balls and bicycle tires and sometimes cars, and they develop "holes" as the hedge gets very old.

Some months ago I posted about a brick wall with a cap.  It looks great but materials per running meter (2 meter high) can be 200,000shs. and labor maybe another 100,000shs.

I live next to a quarry, where the stone is used as hardcore under foundations and floors or crushed to make aggregrate.  After some dry stack retaining walls I wanted a 2 m high garden wall.  I think materials is under 75,000 per running meter.  Eventually maybe we can do drystack.

 It is odd that many people notice the house behind, mainly because it is so big.  This wall had to partly be done becuase i moved the gate and had this uggly hole.  I get many positive comments when people wee this wall and they ask how much.

I am continuing on the other side but will try:
-with clay mortar
-1/2 height
-stone up 30 cm and then rammed earth.