It's not whether you screw up, it's how you recover! You recovered beautifully. Next time that happens, you could just overlay a thin styrene sheet over the bad surface. Use 0.010" styrene so it doesn't change the thickness too much. I was building my Essex Carrier and set up a white cardboard piece to provide a blank photo background. What I didn't know at the time was the cardboard was leaning on an open bottle of Tamiya liquid cement. This was the last thing I did for the day. The cardboard tipped over the bottle which soaked my Corian work surface. Corian is unaffected by solvent, but the Essex Island sitting on it was. When I got to the shop the next day, the island was glued to the Corian and the solvent had wicked halfway up the island's wall. Someone suggested to "re-skin it". I did and saved the model. Who did the 3D printing?