Owning an Ultimaker myself, I can say that it isn't great for printing twisty puzzles. It works fine for very simple designs (e.g. a 1x2x3), but it is hard to print more complex parts, mostly because support material must be printed in the same material as the model. There have recently been talks of a dual extruder upgrade that might soon be available for the Ultimaker, but I can't be sure how much it would help. That being said, I have used the printer a few times for testing individual parts. For example, before I ordered the full print of my Geary Master Pentultimate
from Shapeways, I printed a few of the geared parts to see if the gears themselves would work, since I had never before tried designing a puzzle with gears. The print came out looking rather messy, but it was good enough for me to see that the parts worked. Overall, I'd say that printing puzzles on the Ultimaker isn't completely out of the question, but that the printer will not become a replacement for Shapeways any time soon.
Only on this forum would people use a V-cube 7 as a size comparison for a cat
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