Purement Anti Microbial Filament Competition
Simple Science Fair project/Toy for kids illustrating the oldest know water pump mechanism!
Print out 1 of each (except the "archimedes.stl" file which is only provided to demonstrate assembly) and one extra washer (the washers are optional but they do help keep things in the case). One long piece of filament to go the length of the screw as a central shaft is all that is required. I have also provided screw holes in both the screw and handle to allow it to be a temporary build or in case you'd like to use them elsewhere. When printing the screw on an FDM printer, watch out for curling. ABS is probably going to require serious attention to keep from making a mess.
I printed in PLA, so when my kids wanted to use it in baths or to pump drinks (7 year old get weird ideas their dads don't always plan for) I had to say no (PLA doesn't like dishwashers or hot soapy water much) but if printed in Purement filament that could change. Getting a perfectly smooth surface on the screw is impossible without serious finishing work and all those imperfections are places for bacteria to set up residency, and while I'm all for kids playing in dirt to keep their immune systems in shape, unwashable things in their mouth just don't seem like a good choice.