Auto fix sandstick

I printed some others sanding sticks and inspired by those models I figured out how good it will be if some part could show the sandpaper grit that is in use.

After some models designed I realized that these could be worked out to keep sandpaper in place without any screw.

So here you are these models.

This is my first item published, so some problems are expected :)

Feel free to make, comment and change !

Parts
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* base: A base with straight surface, one side curved and o