MJHEED

I have the exact same Ultimaker (2 upgraded to 2+) and the exact same problem (back left higher than back right) and no way to level the back. It causes my latest large print to fail every time. Why oh why did they only put ONE adjustment in the back? I hope someone at Ultimaker has ideas about how can we fix this.

So, still using the sanded plate. No heat still makes it not stick very well. With 50 to 60 bed heat, my parts bond a little too strongly. I end up breaking the bottom layers of most of my builds. So, I've come to the conclusion that my best option with the fleks3d is to use rafts. Then it can destroy the raft without hurting my build.

Update2: The difficult job finished with no more pieces loose. However, I'm really starting to second guess this cold build plate idea. ALL of the pieces had weak bottom layers. About 6 of the 72 pieces bottoms peeled off easily. Wouldn't a warmer build plate help this? So, I just printed a small test cube with the Fleks3D heated to the normal 60ºC, and it printed fine, adhered well, popped off with normal effort, and my bottom layer is solid again. I have 2 Fleks3D plates, so I'm going to experiment more with the sanded one and try different temperatures. I think a new plate with that amazing matte finish surface will bond with a cold plate. But once you sand it, you might need some heat.

I just got my Fleks3d plate today and my first print (a difficult model that failed to adhere to my glass & glue-stick build plate 6 times) finally printed and stuck.... and like you, it stuck TOO WELL. It fused with the plate. The instructions said no heat, or if you use heat, no more than 37 C. So I printed at 36 C thinking this was going to be a challenging print. Using a blade (sharp scraper) I finally got most of it off, but still had to sand it with emery cloth to get the rest off. But, my blade put some good scratches in the surface. I wrote Fleks3D and explained what happened, with photos, and the owner/creator, Viktor, replied immediately. He agreed that the initial bond can be very strong on a new plate. He said not to worry, that I could sand the plate with 100 grit (coarse) sand paper and it would restore the adhesion properties. He also suggested I print without any heat. So, I sanded the whole plate with 80 grit sand paper (didn't have 100), and printed something a little less challenging (a 2'x3' bracket) and it printed flawlessly and popped off the plate with a tiny flex of the plate. Now, I'm printing that darn tough one again.... so far it looks good. We'll see how easily it comes off the plate this time. So, no heat and sanding with 100 grit seems to have solved my issues. I also manual level (because I have a UM2+). I think Flex3D recommends this, as auto-leveling systems can burn the plate. Good luck! I hope you get it working more reliably. It is really satisfying giving a little twist/bend and having everything pop off cleanly. MJ Update1: Just checked the job.... 1 small piece popped off mid-print! Dang. Managed to pause the job and sticky-tac it back in place. There are 72 small pieces, so losing 1 isn't a big deal, as long as the failed part isn't left to make a mess of the rest of the job. Now stuck back in place, the job is proceeding smoothly. But, that tells me, either sanding it, or having NO heat at all, has made it much much less adhesive. I'm going to have to experiment with different temperatures with this sanded surface to see if a little heat would help the sanded surface regain a little of that extreme adhesion the new plate had.