If you're like me, you have one big problem when trying to dry your hands. Picture this: wet hands, you reach towards a paper towel hanging conveniently next to the sink. You grab the desired towel and pull, trying to tear the perforated lines, but to your dismay, the roll rolls freely, dispensing more paper. In order to tear your paper from here you must use your other wet hand and grab a paper towel you didn't want to use and tear at the line, leaving wet fingerprints for the next person to deal with when they tear the paper. I designed this simple mechanism with that issue in mind. With one hand, pull the lever to move a simple compliant lock upwards, allowing you to dispense the desired amount of paper. When you're done, simply let go of the lever and lock your paper towel roll in place so the tear can be done without touching any paper towels but the one you want to use. 

To print, you'll need to split it up into multiple parts in your slicer, as the pieces are each really big. It is also advised you measure based on the paper towel brand of your choice. I used a bounty roll to determine the sizes. Assembly is as simple as inserting the tube into the bottom of the gear, putting the compliant spring inside the gear, and inserting the whole mechanism on top of the side piece, with the lever going through the hole in the side. The other side of the holder should screw together for easy removal of your paper towel roll once it is depleted.