I designed this spool holder with inspiration from this video (3DPN: Spool Holder Using Paper Towel Cardboard Tubes). The difference in my design is that I used the cardboard tube from a tin foil roll. These cardboard tubes are way stronger than paper towel roll tubes so they hold up a lot better. I also added an angle to the tube, that way there is no need for an end to keep the spool on because it will just slide to the side of the roll. To make printing easy this desing was made to use minimal supports, the only supports needed would be the inside tube if you wanted but it will not be seen. Using the cardboard tube both saves plastic and recycles the tube.
There are two styles for this design one has the 3dpn text on it and the other design is plain. If you are going to print with the text I recommend doing a filament swap for the bottom 1mm and the top 1mm so that the text is more visible.