The Base Ring on our IKEA KNAPPA lamp got baked and brittle over the years, so I made a replacement. With care, this can be replaced without taking apart the entire lamp. I printed in PET-G due to better heat performance than PLA, but higher temp filaments should work as well. Would also recommend white filament for aesthetics and avoid dark colors to limit heat absorption. The white PET-G I had was crap, so I had to go with Prusa Orange (pics).

I added 2mm X 4mm notches around perimeter to the design after the initial print. I didn't realize how essential they were to holding the lamp ribs, and ended up cutting into the initial print with a file. I did NOT reprint with the perimeter notches to check the fit, but this published model represents what I ended up with after printing and post work. Buyer beware.

WARNING: Please be conscious about using a temperature-stable filament, as this piece is in very close proximity to a heat source (light bulb), and could represent a fire hazard if the filament softens or comes in contact with the bulb! Even LED bulbs can generate a significant amount of heat at the base, as the base is frequently used as a heat sink. IF THESE ARE RISKS YOU DO NOT UNDERSTAND, DO NOT USE THIS MODEL!!!