Hand machined mechanical pencils

Valved top for drinks bottle (22/09/12)

I made this adapter to screw on to the top of a standard 2L drinks bottle so it could be used as a low-pressure air reservoir. The valve body is threaded with a PCO1810 thread (see this page for more details on the two common bottle threads). The valve "stem" is actuated by an external knob and has a quarter turn of movement. There is an inlet connection for the air compressor (a little diaphragm pump) and the valve is in the outlet side. The last few photos show it being used with my homemade hot-air pencil.


For what it's worth, here's a PDF drawing of the valve - it should give you a better idea of the construction.