Build a long reach pvc water pump, handy for pumping right down to the bottom, and easily transfer water between rain barrels without resorting to the small plastic 5 litre paint buckets that fit the opening.
I had hoped that this small scale pumping windmill copy would start siphoning once I pulled the plunger past the T piece, alas the reducing internal diameter of the T is smaller than the internal diameter of the 50mm pvc pipe which makes it difficult to pull the plunger past the T.
Experiments have shown that the standing water level needs to be halfway up the inlet pipe, roughly 500mm high for the syphoning action to occur.
A check valve, made out of a hollow plastic ball found in roll-on deodorants, right at the bottom of the inlet pipe, ensures that you dont have to pull on the plunger like a stark raving lunatic in order to raise water.
~Now updated with a better valve~
Not a whole lot of tools needed, I used a hacksaw, pliers, soldering iron and a M5 die for threading the 5mm steel plunger rod.
In addition you will need,
a short length of thin wire used as a ball valve retainer to keep the ball near the seat when not sealing.Not needed if using updated butterfly valve
leather, enough for 2 x 50mm dia discs. 1 for the plunger and 1 in the cap used as a rod shaft seal.
I used 105cm for the inlet, 20cm for the outlet cross piece and 75cm for the outlet down piece, I had a 40mm scrap piece for the join between the top cap and T piece.