How to Fix Z

Are your 3D prints emerging with noticeable horizontal lines? That's Z-banding. Here are the ways you can fix it.

Z-banding, Z-wobble, ribbing, and ringing are different names for the same issue in 3D printing. Your 3D model looks perfect when sliced, but the finished 3D print has distinct horizontal lines.

There are a number of 3D printer issues that will cause Z-banding. As such, diagnosing the problem causing Z-banding with your 3D prints is a challenge, and it's always worth starting with the easiest potential solution.

But where should you start? Let's learn how to fix Z-banding in 3D prints, starting with the most straightforward methods and working towards the hardest.

Most hobbyist 3D printers are assembled with frames that are bolted together. These bolts need to be tight, or the 3D printer will flex and move as the heavy hotend moves around, leading to issues like gantry wobble. Gantry wobble and other minor hardware problems are common causes of Z-banding.

Start by finding and tightening all the bolts that hold together your 3D printer. Bolts can loosen over time, especially when holding together a machine that moves, but tightening them will fix the issue. If this doesn't work, you can also try a couple of other quick hardware fixes.

Bent or damaged lead screws can have the same impact as gantry wobble, and you can test for this issue by manually moving your hotend up and down. If it isn't smooth, it's time to consider replacing your lead screw.

While there are alternatives like rails on the market, most hobbyist 3D printers use timing belts to turn the rotational movement of stepper motors into the linear movement of the print head.

When a timing belt is too loose, it can slip, causing the print head to move less or more than the software expects. This creates defects like Z-banding. Likewise, timing belts that are too tight can also cause printing defects. Your timing belts should be tight enough to hug the pulleys they sit on without slipping while being loose enough to offer a small amount of flex.

Many 3D printers have belt tensioners built-in, usually at the point where the ends of the belts meet. Refer to your printer's manual to see how to adjust these tensioners properly. If your printer doesn't have adjustable tensioners, you can buy small tension springs to add tension to your belts.

Even if the rest of your printer is perfect, hotend installation issues can wreak havoc on your 3D prints. While Z-banding isn't commonly caused by your hotend, issues like blocked nozzles and loose mounts can cause defects that look very similar.

It isn't always apparent when a hotend is installed incorrectly. Refer to your printer's instructions and try to take apart and rebuild the hotend, as this can help to solve little installation problems that aren't easy to see.

You can also find guides to help you take apart and reassembled popular printers, such as ours on how to assemble the Ender 3 V2. Blocked nozzles and other faulty hotend hardware is best replaced.

Most hobbyist 3D printers don't have ways to measure the filament that they extrude. Instead, they have to rely on carefully calibrated variables to ensure that each motor moves the correct distance based on the G-code instructions that it receives.

The e-step variable is responsible for telling the 3D printer how far an extruder motor needs to move to extrude 1mm of material. If this number is too low, under-extrusion will occur. If it is too high, over-extrusion will occur. Both of these issues can cause Z-banding.

Thankfully, calibrating your e-steps isn't too hard. It is worth looking up a guide that corresponds to your printer's firmware, as this will tell you exactly how to go through the process on your own printer.

As any experienced 3D printing enthusiast will tell you, even small differences in print temperature can have a drastic impact on a finished 3D print. This means that inconsistent print temperatures during printing can cause defects, including Z-banding. But how do you ensure that your hotend and bed are always at the right temperature?

PID tuning is the answer. Most 3D printers use three separate values to control the heated components they have onboard: P, I, and D. These values are stored in the printer's memory so that the firmware can access them.

Common 3D printer firmware options, like Marlin 1, Marlin 2, and Smoothieware, come with automatic PID tuning tools that handle the process of PID tuning for you. You just need to figure out which firmware your 3D printer uses to get started.

3D printer extruders use a motor and gear system to draw filament into the hotend. If these gears are too tight, the filament will get compressed and may slip, causing under-extrusion. Likewise, loose extruder gears will also cause under-extrusion.

Tensioning your extruder gears is usually as simple as adjusting a single bolt. You will need to experiment a little to find the perfect balance for your extruder gears, and this is something you may need to check down the line.

Testing your 3D printer to make sure that Z-banding is no longer happening is a crucial stage in this process. There are plenty of ways to test your 3D printer, but printing something will always be the best way to know for sure.

A calibration cube model is a good place to start. You can find models like this on most 3D model platforms, and you will be able to use your regular slicer settings to set up the print. It's worth using a light-colored filament as this will make it easier to see imperfections in your print.

Of course, fixing a problem like Z-banding isn't all you can do with a calibration cube. Learning how to calibrate your 3D printer is a great way to improve the quality of your prints, and the web is filled with resources to help you.

Z-banding is a frustrating issue to come across, especially if you don't have much 3D printing experience. Thankfully, though, there are plenty of methods that you can try when you are troubleshooting 3D printer Z-banding.

Regular servicing is a big part of this. You can avoid 3D printer issues before they rear their head, but you need to keep on top of maintaining the machine. The more you use your 3D printer, the more care it requires.

Samuel is a UK-based technology writer with a passion for all things DIY. Having started businesses in the fields of web development and 3D printing, along with working as a writer for many years, Samuel offers a unique insight into the world of technology. Focusing mainly on DIY tech projects, he loves nothing more than sharing fun and exciting ideas that you can try at home. Outside of work, Samuel can usually be found cycling, playing PC video games, or desperately attempting to communicate with his pet crab.