This is a project I made after I got annoyed by performing break-dance when trying to open doors without touching the handle. It's just a quick shot on the problem and surely can be improved in quite some ways, but the focus was on creating a simple and easy to print (or to build in other ways) tool without using up too much time. Maybe it's a silly idea, but I find it's at least better than using your sleeves or elbows. There is a little carving to add rubber bands to get better friction and to protect the door when you push it with the tool, but currently the bands tend to peel off when stashing or removing the handler in and out of the jeans watch pocket. There is a hole for attachment but that might only make sense with a retracting line. I will make another version tomorrow with some more rounding on the edges to protect the rubber band to get cut and a deeper carving for the bands so they don't slide of. Right now you might work a little on the edges of the finished print and smooth them with sand paper. Some more ideas would be to maybe make a rubber band retractable lid for the front part that touches the handle or maybe a (magnet) belt holder. The thumb rest might also be better if it's a little bit lower. Another idea was to reduce the touching area by adding a triangle edge inside the front u-shaped part. So you see I left some things for you to go on with it if you like :-)
=== Notes on Cleaning PLA
PLA is not the best material to clean: the printed surface is not totally even and although you can rinse it with boiled water for some seconds without a problem, you can't cover it with it. The PLA will get soft in a short time due to the heat therefore dish washers are also no option. Ethanol is possible but I read it tends to make PLA brittle over time. Maybe coating the tool with some protective layer like spray paint could help.
=== Important Note about Stability and Print Settings
For the print I used 15% filling with the wonderful Gyroid pattern and it seems to be quite stable though I DID NOT TRY OUT THE FORCE IT TAKES TO BREAK IT. You might want to experiment with a higher filling density. The print nozzle was 0.4mm and layer height was 0.15mm. With this settings it uses up around 5 meters of PLA and takes about 1 hour and 40 minutes on an MK3s.
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