Semi-disposable volumetric pippete.
This pippete is now my standart. It's the result of a slow evolution. Now I don't know how I managed to do my hobby before I had it. It can
measure and carry volumes compatible with my 50ml centrifugue tube glassware.
I made about 10 of them, and every now and then make another one. Its so cheap I can reserve some to specific chemicals so I don't have to wash
them.
The measuring of the air in the syringe is a quite precise measurement of the liquid that gets sucked in the glass, that is: displace the plunge 5ml
and you have 5ml of liquid in the glass. This sound obvious, but I think I’d better make it clear.
The making is straighfoward: Make a constraint in a 10mm glass tube, cut, heat the tip until the hole in the glass is small enough, cut the tube to
about 20cm, put a latex tube that fits the tube and the syringue (the needle-holding rim is about 10mm diamet.). hold everything together with plastic
straps, the kind used to hold wires together, any hardware shop should have them.
Voila.
Picture attached.
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