PETamentor2 extra's.

BOTTLE RIBBON SLITTER
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A new PET bottle slitter for the PETamentor2. The PETamentor 2 got me 'hooked'
on making my own filament. See https://www.thingiverse.com/thing:5435208

It seemed to make a terrible noise cutting the bottle so I thought I would modify the
blade to a 'slitting' action rather than presenting the bottle 'square on' to the blade.

I felt that a 'slitting' action may also need less force since it has more 'shearing' action
like the ground wheels type of cutter people use.

FILAMENT COLOURING PEN
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This 'paints' the inside face of the cut plastic strip just before it enters the extruder.

BOTTLE AUTO STOP SWITCH
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This allows you to leave the machine running unattended and stops the extrusion when
the bottle is nearly finished.

BOTTLE 'WEIGHT' MECHANISM
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This 'constrains' the bot