5 Making the Inlets and Outlets
Holes in the tank for the inlet and outlet are made using a jigsaw:
• Mark out the hole – 4” diameter
• Drill a small hole for the jigsaw blade to pass through.
• Cut with the jigsaw – lay the cutting surface horizontally if possible for accuracy
• Finish the hole to the line you have marked using a file.
Make the initial cut based on the hole you have marked Check that it is large enough for the fitting
Cut again or file the hole bigger until it is the right size. If you do not have a jigsaw, then drill small holes.
Then cut through with a fine chisel using hammer blows.
Ensure the 4” male fitting fits all the way into the hole. Screw it in with a large pipe wrench (photo 11). This
is easier to do with two people. This wrench will later be used for tightening the male and female threaded
fittings, either side of the inlet.