Here is another question I answered from the now defunct Makers StackExchange.

Question:

Periodically I’ll have a raftless print that is just glued to the heated print bed of my replicator (usually if the print has a large flat base). I’ve tried using a spatula and the like, but this tends to damage my print, or at the very least, the kapton tape. Just removing the kapton tape will usually dislodge the print, but replacing the tape is a huge pain…

What’s the best way to deal with a stuck print?

My Answer:

Turn the heat off on your heated build platform and wait for it to cool. The closer to room temperature, the easier it will be to remove. And if you are printing directly to glass, letting the heated build platform cool all the way down to room temperature your 3D print will lift off without any effort at all. You also won’t need to keep replacing the kapton tape.

But that takes so long! I hear you say, I want my 3D print now! Sometimes when doing a big batch of printing, I also run into this problem. I cool the heated build platform, and when its temperature has dropped to around 50°C, the print has cooled enough to have a fairly rigid base. I usually then get a small flat head screwdriver and place it near a corner (at the bottom, near the build platform). A small sharp tap on the end of the screwdriver from a hammer is enough to make it come free.