Print Bed Cold Spots?

Hello Everyone.

Awhile back I reported an issue where I thought my z-axis was compressing as I had prints that were skewed. During this time I was also having prints curl. I originally thought it was because I was experimenting with my settings a little too much, but have since found what I believe to be the real problem. During the problem prints, they were long items that I laid diagonally across the print bed, from corner to corner, and was seeing them curl on the edges. However, I also had another part, a smaller piece that was maybe an inch or two wide that I printed in the corner as well. This is when I discovered what I believe to be the problem.

I believe the corners of the Lulzbot Mini bed are cold spots. I watched as this smaller model was curling off the bed in a corner that was closer to the edge, while the other 3 corners of the model stayed put. I talked with a friend and he told me that glass makes a better insulator then conductor.

Has anyone else seen similar findings? I don’t have a way to actually measure the thermal readings coming from my bed, but I have about 5-6 pieces of a model that support this assumption. (I also ask this because I recently had to replace my print bed after the last one cracked, and want to make sure I didn’t get a faulty replacement)

I experienced the same issue. Using an IR temperature monitor, I found there are several cold regions on the bed. In hot spots where the ABS does not stick, the print object curled. I have been compensating by using a large brim (10 beads) to help adhearance to the bed and (or) moving to the print to the right side of the bed that is consistently hotter.