BUILDING AN AIR TANK IN UNDER TEN MINUTES.
 
What you need.
Cola bottle (600ml is good) PET plastic.
An empty pen tube ( the ink part)
Some lego hose
 
TOOLS
T-20 star screwdriver bit.
small drill bit or jewellers crew driver, phillips head
(thisneeds to be just bigg enough to make a hole for the driver bit or equivelent.)
 
DO IT
Take the lid off your washed and dried bottle, Keep the plastic seal inside as this helps keep the seal.
 
Now using your small drill or sharp implement ,make a pilot hole to one side of the lid from the outside in.
Make sure you are far enough in that the hose will clear the side of the bottle.

If you intend to use a T-peice on your hose to go to the pump and the switch then you only need one hole and a Lego T-peice in the hose.
 
If you want an in line and an out line then make two holes in the lid. This also lets you have two pumps on seperate lines to increase the ratio of inlet pipe to outlet
By only adding one T-peice to a line.
That means you can get air in faster then it comes out. if your pump is fast enough.
 
Now feed the hose though the lid from the outside in , this is the easisest way as the hole will slope in because you made the hole from the outside as well, pass at least 3 cm inside for now.

If you intend to use a T-peice on your hose to go to the pump and the switch then you only need one hole and a Lego T-peice in the hose.
 
If you want an in line and an out line then make two holes in the lid. This also lets you have two pumps on seperate lines to increase the ratio of inlet pipe to outlet
By only adding one T-peice to a line.
That means you can get air in faster then it comes out. if your pump is fast enough.
 
Now feed the hose though the lid from the outside in , this is the easisest way as the hole will slope in because you made the hole from the outside as well, pass at least 3 cm inside for now.