I started getting some strange z-banding on my prints, and for the life of me I couldn’t figure out why. I had read a lot of blog posts, watched videos, and really couldn’t find anything but a small blurb buried on a support site for a different model printer that barely came close to what I was experiencing. But even that was little help because there were no pictures that went along with it. I had to really look at the whole scenario in order to fix this odd z-banding problem I was facing. To help you understand, a little backstory.

I know Makerbot got a lot of bad press back around 2012-15ish, But they really have gotten much better in terms of quality. I recently purchased my second Makerbot 5th gen second-hand from another printer friend of mine, located in Fremont, Tan3D. It was an older 5th gen, but he said he had been taking care of it, and was still producing good prints. On top of everything he gave me a great deal on it.

When I went to pick it up, I noticed that there were some globs of grease on the main lead screw and the two z-rods on either side. He said that he had been using that grease to lube the lead screw occasionally and he gave me some for the road. I hadn’t had to lube my previous machine, but I knew his was much older so I didn’t think much of it.

When I got it home I printed a few test objects and was really happy withe the results. However I noticed that the grease he put on was to high, and was not being worked into the lead screw. I took a micro fiber cloth and wiped it on the lower part of the lead screw and everything seemed fine. About two or three prints later I started getting results like in the picture below.

It wasn’t super pronounced, or even consistent for that matter, but it started getting worse. The prints would be so weak that you could just pull the bottom layer right off… I tried searching google for z-banding issues, but they all pointed toward a bent lead screw. I started to get really worried that I would have to find a replacement, and for Makerbot, that can be difficult/expensive. But every picture I saw, the z-banding was consistent throughout the print, and wavy in the sense that the layers seems to sway back and forth. Like below.

Nearly at my wits end, I decided to just buckle down and watch a test print from beginning to end. I started noticing the pattern…It seemed like the lead screw would barely move for some layers and move quite a bit for others. It would squish one layer into the previous, and almost print above the last layer for the next. So on and so on creating that pattern, and then it would decide to print normally.

The grease that the previous owner put on was the only odd factor. But I kept dismissing it as he said he had done it often. Which also didn’t exactly explain why it would just stop randomly.

The random article that I mentioned earlier did say that too much grease can affect print quality in a way that looks like z-banding, but it wasn’t direct enough to draw a correlation, but I did keep it at the back of my mind.

I was running out of ideas, so I decided to take all the grease off that the previous owner had put on. That’s when the real project began. There seemed to be gunk in a lot of places, so I made the decision to take it all apart and give it a good cleaning. I had replaced the idler pulley on my first Makerbot before in a previous article, but removing the lead screw seemed like it was going to be an even bigger chore, and it was!

I should have taken a video, but I did manage to snap a picture of the printer without its backing. Long story short, I removed the print bed carriage and the lead screw, de-greased the crap out of it with a boat load of WD40, and reassembled it (I didn’t even lose a screw!).

I was so pleased when I ran the test print and it came out clean and sharp. Like it was brand new! I went ahead and ordered some SuperLube with PTFE that Makerbot recommends for its Z18 model and applied just a tiny little bit to the lead screw only. I didn’t want the lead screw to seize from the WD40 (WD40 cleans, and de-rusts, but it is not a lubricant!).

Having pretty much fully disassembled the Makerbot 5th Gen, I feel very confident that if any other problem should arise, I will be able to handle it. I am sticking with Makerbot because they are great machines, and if you take care of them, they will take care of you! And most importantly I am happy to say that I am still getting great prints.

The End