***** Note: Before printing this part, please make sure to measure the outer diameter of the roller arm on your printer first. Many users have found that it doesn't fit their printer's roller arm after printing the part - it is speculated that Creality uses different diameter metal profiles in its various printers. Some users have reported that this design seems to be specifically for the first-generation CR-10 models.

If you are still determined to print this part, but you don't have a caliper on hand to accurately measure the diameter of the roller rack arm, then to avoid adding unnecessary disappointment, you might as well take a more cautious approach: first, print just a few layers, pause the printing process, and check carefully to ensure that the printed component can be smoothly installed on your roller rack arm.

I designed this adapter myself in Fusion 360, as the original Creality CR-10 roller rack arm was not equipped with a suitable bushing or adapter. The thread of the adapter has almost no clearance and no dimensional adjustments were made for tolerances. After removing it from the printing platform, the thread was easy and smooth to use, and it even completely cleaned up the tiny burrs left by the current PETG material.

This adapter extends along the entire length of the roller rack arm, allowing me to firmly fix the large rolls I often use in place, while rotating them effortlessly. For small rolls like those standard with printers, all I need to do is invert the female threaded end, and it will fit perfectly, ensuring a secure and reliable installation.

In the future, I might add a hexagonal head or other anti-slip raised structures to the adapter to make it easier to screw and unscrew the nut. After all, the nut fits very tightly with the coiled material, and if you're not careful, it might be difficult to remove it.

If you encounter a situation where the diameter of the roll material exceeds 60mm during the process of printing and using this adapter, and you are unwilling or unable to modify the adapter, please feel free to let me know at any time. I would be very happy to update and optimize the design for you.

If you have successfully printed and used this adapter, please don't hesitate to share your experience and actual results. Thank you for your support and feedback!