Adjustable Volume Straw Pipette (simpler plunger)

thingiverse

This pipette is based on Thingiverse's design (http://www.thingiverse.com/thing:64977) but features a few tweaks. The threaded bolt was removed from the plunger and replaced with an M4 bolt for increased length (75mm). The thumb gears were also modified to accommodate the new rod. The top part was made more robust for better printing, while all models were rotated around the X axis for easier setup. Despite some initial air-tightness issues, these were solved through ABS paint and straw sealing. Lab gloves served as membranes, but an extra layer improved performance with 200 microliter tips. Testing for consistency is underway in a real lab. For printing, follow the instructions at the original design site, screw in a M4 75mm bolt into the plunger, and continue with the original design's directions.