How to Adjust the Eccentric Nuts on the Ender 3 (Pro/V2)?

Frequently maintaining your Ender 3 is a vital part of obtaining successful, high-quality 3D printed models and ensuring that the 3D printer stays in good shape for an extended amount of time without the need for repairs or replacement.

Because of this, familiarizing yourself with all the components of your Ender 3, especially the mechanical ones that often require maintenance in one way or the other, is one of the best skills you can pick up for a smooth 3D printing journey.

In today’s article, we will focus on the components known as eccentric nuts that you can find in various parts of your Ender 3, which are components that are vital to adjust correctly for a successful 3D printing process without any mechanical problems related to the moving parts of the 3D printer.

So, how can you adjust the eccentric nuts on your Ender 3?

As the eccentric nuts are different than regular nuts, with each complete turn in either direction putting the tightness of the eccentric nut at the same level, correctly adjusting them comes down to rotating them very slowly and observing the tension between the rollers and the rail.

Next up, we will dive deeper into the process of adjusting the eccentric nuts on the Ender 3, discuss the purpose the eccentric nuts serve in detail, and finally, go through the locations where you can find eccentric nuts on your Ender 3. 

How to Adjust the Eccentric Nuts on the Ender 3 (Pro/V2)?

While adjusting the eccentric nuts on your Ender 3 is a straightforward process that won’t take much of your time or effort, the first vital step in achieving the correct adjustment level is understanding how these components operate.

Unlike regular nuts that get tighter the more you turn it clockwise and looser the more you turn it counter-clockwise, eccentric nuts are designed in a way that causes the tightness to be based on the rotational positioning of the nut in a 360-degree area.

As a result, each complete turn you apply to an eccentric nut, regardless of the direction, will only cause it to be back at the same position as before you started turning it, unlike a regular nut that has either loosened or tightened depending on the direction.

With this in mind, to adjust the eccentric nuts on your Ender 3, the two things to keep in mind are to perform very slight rotations due to the impact of each small rotation and to observe the effects of the rotations you have performed to find out whether the adjustment was successful or not.

It’s worth mentioning that the process of adjusting the eccentric nuts won’t require anything other than a standard wrench that matches the size of the eccentric nuts (10 mm), which, by default, is one of the two wrenches that ship with your Ender 3.

For best results, the eccentric nuts should be configured in a way that allows the rollers to move smoothly on the rail (you should easily be able to push them in either direction), and the rollers should never wobble, regardless of how much force you apply to the brackets that connect them to the rail.

While it may take some practice to get the eccentric nuts correctly configured, being patient and avoiding large turns to the eccentric nuts will allow you to get through the process quicker and smoother.

What Is the Purpose of the Eccentric Nuts on the Ender 3 (Pro/V2)?

While the eccentric nuts look like nothing special, just like standard nuts and bolts, from the outside at first look, they actually fulfill a vital role in ensuring that the mechanical parts of your Ender 3 function correctly and without any errors.

The purpose of the eccentric nuts on the Ender 3 is pretty straightforward, which is to adjust how tightly the rollers that are responsible for providing a smooth movement to the printhead on the X and the Z axes, and the build plate on the Y axis, are attached to the corresponding rails.

As a result, when the eccentric nuts are way too tight, the rollers will also end up gripping the rail way too tightly, which will prevent them from spinning smoothly on the rails and end up grinding instead, causing inconsistencies in movement and potentially causing damage to both themselves and the rail.

On the other hand, when the eccentric nuts are too loose, the rollers won’t stay attached to the rail, ending up wobbling and potentially entirely losing connection with the rail and floating above. In such a scenario, the axes will have issues with movement once again, causing inconsistencies.

Where Can You Find the Eccentric Nuts on the Ender 3 (Pro/V2)?

There are a number of eccentric nuts that are connected to various parts of your Ender 3, and due to their positioning, you may not directly notice them unless you take a thorough look at all the areas of the 3D printer with the purpose of finding them.

You can find the eccentric nuts of your Ender 3 behind every roller that connects either the printhead or the build plate to the X, Y, or Z-axis rails, in the space between the roller and the bracket that holds the roller in its place.

From the outside, it will look just like a regular nut that you can turn with a standard wrench that matches its size, as the part that makes the eccentric nut different than standard nuts is located inside and does not affect how you will see it, meaning that you don’t have to look for something particularly unique.

While you may not have noticed their existence at first glimpse, they’re surprisingly easy to find if you take a closer look at the space between the rollers and the brackets they are attached to, as they are pretty large in size, which makes them pretty straightforward to notice.

Wrapping Up

After you get a good understanding of how the eccentric nuts function, adjusting them will be a quick and straightforward process that will yield incredible benefits for your Ender 3, especially if the eccentric nuts weren’t already optimally adjusted.

To quickly recap, the tightness of an eccentric nut depends on its position in a 360-degree space, unlike regular nuts that tighten as long as you rotate them clockwise and loosen as long as you turn them counter-clockwise. 

As a result, adjusting an eccentric nut requires small and precise turns while observing the impact of the turns on the spacing between the rollers and the rail instead of applying multiple complete rotations in either direction to tighten or loosen it like you would with a regular nut.

Happy printing!