Elephant's foot

Elephant's foot describes a small but noticeable bulge at the very bottom of a print, where the first several layers end up a bit wider than the layers above them. The name comes from the resemblance to a slightly flared foot, and it happens because those bottom layers are still soft and get squeezed outward under the weight of everything printed on top of them.

The main cause is usually a bed or nozzle that runs a touch too hot for those first layers combined with too little cooling early on, which keeps the base soft for longer while more weight builds up above it. A first layer that is squished slightly too flat because the nozzle sits a bit too close to the bed can make the effect more visible as well.

Elephant's foot mostly matters for parts that need to fit precisely into something else, since that extra width at the base can stop a snug-fitting piece from seating properly. A slicer setting that slightly shrinks the very first layers, sometimes labeled as elephant's foot compensation, corrects for it directly. A common mistake is sanding the bulge down repeatedly instead of fixing the temperature or first layer settings causing it.