Friday, 6 March 2015

March 2015 (2).

The Ecobed's walls are lined with 200um builders plastic.  Its 2m wide which is just enough to cover the bottom of the tank and 250mm up each side.  The ends of the sheet can be taken to the top of the end walls because I buy it in a 10m length.  First I cut the plastic to the exact length required so its easier to handle (should be 3750mm, but its best to check).  I then staple the middle of each end to the middle of each end wall (at the top).  Next I pull all the creases out and run the sheet evenly up the side walls.  I then staple the tops of the sheet all round the bed except in the corners.  I fold the corners carefully and finish stapling as shown.  Its important when folding corners to keep the edges of the sheet above the overflow level. This corner was not a good example and had to be re-folded.  Can you see why?

A second layer of plastic is added for security.  This gives me a water tank 250mm deep and covers the end walls to protect the timber from microbial attack and keeps the timber's preservatives out of the bed.  The sides are each covered with an extra sheet of plastic so the timber does not come into contact with the soil.  I am careful not to staple through the plastic below the overflow height.

This 50mm corrugated irrigation tube has lots of slotted holes in its wall and is being placed around the inside perimeter of the water tank.  It distributes water quickly when filling the tank and adds a little to the tank's water storage capacity.

Here I'm marking the position of the overflow pipe and coupling on the filler tube so they line up with the hole previously drilled in the side wall.  The top of the filler pipe was marked 100mm above the Ecobed wall so that it can be cut to match the other Ecobeds.

The filler tube was carefully marked on each side of the overflow coupling and the coupling removed.  A 38mm hole was then drilled with a hole saw through one side of the tube midway between these 2 marks.  The 2 couplings were then moved back into position, set at 90 degrees to each other and glued in place using clear silicone sealant.  The overflow tube was then glued in position in the overflow coupling.  The assembly needs to be set firmly before installing it in the Ecobed.