The bottom 1–3 layers of the print are wider than the rest. Looking from the side, the base flares outward slightly. On precision parts, this makes the bottom layer too wide to fit into assemblies, and interferes with flat surfaces resting flush on a table.
Confirm It’s Elephant Foot, Not Just Over-Extrusion
Measure the print width at the base vs. 10mm up. If the base is wider and the upper portion is accurate, it’s elephant foot. If the print is consistently oversized at all heights, it’s an extrusion calibration issue — see the Dimensional Accuracy guide.
Elephant foot specifically affects the bottom 1–4 layers, then disappears as the print rises away from the heated bed.
Why It Happens
The first layer is pressed into the bed under extra pressure (by design — squish is necessary for adhesion). The heated bed keeps the bottom layers soft longer than the upper layers. Combined, the weight of material above presses down and spreads the bottom layers outward.
Fix in This Order
1. Z-offset is the primary control. Raise Z-offset by 0.02–0.05mm increments. This reduces squish on the first layer, which reduces lateral spread. Stop when elephant foot disappears but before the first layer loses adhesion. Most cases need less than 0.1mm adjustment.
2. Reduce bed temperature 5°C. A cooler bed allows the bottom layers to solidify faster, reducing the window where they spread. For PLA at 60°C, try 55°C. Don’t go so low that adhesion fails.
3. Use elephant foot compensation in the slicer. PrusaSlicer, OrcaSlicer, and Bambu Studio all have this setting. Start at 0.1mm and adjust. This adds an inward compensation to only the first N layers. It’s the most surgical fix but doesn’t address the root cause.
4. Enable minimal fan speed from layer 2. 20–30% fan starting on layer 2 cools the base faster and limits how long the bottom layers stay soft.
What Not to Do
Reducing first layer flow rate below 90% to fight elephant foot. You’ll lose adhesion before you fix the shape problem — the squish from Z-offset is what causes the spread, not the amount of material. Fix Z-offset first.