A universal cap for paper tubes, plastic pipes, round containers, etc. The model is designed to be fully parametric, so you can easily generate and print any size you need directly in the MakerWorld Customizer. The inside of the cap features beveled ribs.

The original model was designed specifically for paper tubes, which often have minor dimensional deviations in diameter or deform over time due to moisture. Because of this, I moved away from a standard plain cap—which often either wouldn't hold or couldn't be put on at all—and added internal conical ribbing to compensate for these irregularities and tolerances. It holds firmly and doesn't slip, yet it can be removed smoothly.

In the generator, you just need to enter the diameter of your tube. It worked best for me to measure the tube's diameter to the nearest tenth of a millimeter and leave the tolerance (clearance) value at 0.1 mm. The cap height is also adjustable.

I recommend printing with a 0.2 mm layer height, the Arachne wall generator, and an elephant foot compensation of 0.15 mm (or according to your printer's calibration).

The uploaded model is pre-configured for a 50 mm tube.