I got home with my new IKEA curtains, slid them onto the fat metal rod, and instantly regretted skipping the little plastic hook things— the fabric was basically grinding along the pole. Instead of making another trip to the store, I opened Fusion 360, sketched a ring, slapped an S-hook on it, and printed a handful. They pop over the rod, give the panel a slick, low-friction glide, and the hook grabs the curtain loop so nothing sags.