DarthBilly

You can do two things here. Feel both rods to see if you can figure out which one is sticking at that spot. If not, you'll have to take each bearing off the bed to find the problem. Or, you could just grease the heck out of both rods and slide it up and down until that spot is gone. If you remove each bearing, and find the sticky one, lube it and slide it up and down until the spot is gone.You may want to take some very fine sand paper or tin foil and sand the rod at the sticky spot (very slightly) until the sticking is gone.

Hi, I've had this problem, a couple of times. I think I actually have is fixed now. Turn everything off and raise and lower your bed manually. Make sure you bring it up to the nozzle. When you lower it, if you notice that it sticks, place your print on the table and compare if it sticks at the same height as your missing layer. If so, your going to have to get some lube and take some stuff a part. Check the rod to see if there's anything on them that may cause it to stick. Take the bearing covers off and tape it to the top. Next take the tread rod nut and unscrew it and then rotate it to the top. Make sure this doesn't stick as well. Now you should be able to freely move the table up and down just on the bearings. Try lubing (Use sewing oil, but I ended up using car bearing grease) to lube the rails and move the bearings up and down until smooth. If that doesn't work, you'll have to find the sticking bearing by removing the screws from them and moving them up and down the rail to see if one sticks and the other doesn't. Just remember when putting everything back together that as use tighten the bearings you move them up and down the rods and that they move freely, no binding.

I had this same issue until I reseated my bearings (which I also took off the threaded z nut). After that the wiggle was gone.

Just a follow up, Second print and still looks good.

clockfiend Thank you for all your hard work, well done!

Ok, here's the latest. I received my new Z shaftes (not the threaded rod). I figured I would trouble shoot this issue since I was going to have some of it apart. I removed the Ultimaker2 plaque and unscrewed the Z nut. I moved the Z nut around the area that has the problem. It felt very smooth. I then moved it towards the top to help hold the plaque. Now that the table was free, I slid it up and down. Here I noticed a snag while going down at the spot of the problem. So I then removed the right-side bearing. I slid it up and down. Bingo, first try, it also snags at the spot. To be sure, I did the same thing to the left side, but it did not snag. I removed the shaft an put in the new one. To my surprise, it doesn't look any better than the original one. I fed the bearing on and moved it up and down and it feels smooth. I put sewing machine oil on a cloth and cleaned the new shaft. As I fitted the shaft, and tighten the bearing, I moved the table up and down to make sure t was still smooth and it was. It was late last night, so I did a print and NO missing layers (YEAH!). I'm going to do some more today, hopefully it's all fixed

Here's a picture of the rods. Yes, I did use a soft cloth to try and remove it, but I can feel it. It has a rough texture.

Hi all, I'm adding my pictures to this issue. I also notice a chip in the bed rods and what appears to be rust on the rods. I've on;y had this printer 6 days :(.[/media][/media]

That's awesome and Beautiful!