In early days of 3d printing I sanded my prints a lot. This is a must have tool. I know there are many versions, but I wanted 3mm needle file to fit in http://www.thingiverse.com/thing:216145. So I decided to create this thing from the ground. Every hole is slightly oversized to match even poor quality printing, but still works.No supports needed. For a good fast print I suggest to turn the cooling fan on, even for abs print. Then you will be able to print this in 7sec/layer or less timeout. Otherwise the edges may float due to the fast layer change. You will need a 3m or 4m screw and nut to hold needle file in place.