Out of the many components that a 3D printer consists of, we can consider the print bed to be one of the most uncomplicated ones, as it’s essentially nothing more than a flat sheet that acts as a surface for your 3D printed model to rest on until the printing process is complete.
On the other hand, surprisingly enough, the print bed is also the source of a considerable number of widespread 3D printing problems, with the most famous example being the bed adhesion issues that occur as a result of a print bed that is not correctly leveled.
In today’s article, we will be talking about one such print bed-related issue that you can come across on your Ender 3, where the bed either ends up being way too low relative to the nozzle, which creates a huge gap after homing the homing process, or too high, which causes the nozzle to crash into the bed.
So, what can cause your Ender 3’s print bed to be too high or too low?
In a nutshell, the primary reason that will cause your Ender 3’s print bed to be too high or too low in relation to the nozzle is an incorrectly positioned Z endstop, which will cause your 3D printer to think that the print bed is closer or further to the nozzle than it actually is.
Next up, we will dive deeper into the reasons that can cause your Ender 3’s bed to be either too low or too high and find out how to fix both of these issues as efficiently as possible to restore the bed’s position to a correct level.
Why Is My Ender 3 (Pro/V2) Bed too Low?
When the bed of your Ender 3 is positioned way too low relative to the nozzle, there will be a big gap between the bed and the nozzle after the homing process is over, which will make it impossible for your 3D printer to conduct the printing process correctly.
Technically, the Ender 3 does not know where the heated bed itself is positioned, as the Z endstop that activates and tells the 3D printer to stop moving the nozzle when the printhead gets close enough to it is the only thing that supplies this data, which is an entirely different entity than the bed.
As a result, in cases where the heated bed and the Z endstop are positioned in a way where the Z endstop ends up being way above the heated bed, the Ender 3 will assume that it’s the lowest point that the printhead can go before crashing into the heated bed and refuse to move it further down.
This scenario will cause an inconsistency between the actual Z position of the print bed and what your Ender 3 thinks is the Z position of the print bed, causing your Ender 3’s bed to always be too low compared to the minimum possible Z position of the nozzle.
Why Is My Ender 3 (Pro/V2) Bed too High?
When the bed of your Ender 3 ends up being way too high, the nozzle can crash into the bed during the homing process due to a lack of space, which can cause significant damage to both the bed and the printhead of your 3D printer.
The cause behind your Ender 3’s bed being too high is practically the same as what would cause your Ender 3’s bed to be too low, but in reverse, where the Z limit switch ends up being at a position lower than it should be, causing the 3D printer to think that there is more room to move the printhead down.
As your Ender 3 has no other frame of reference for determining the minimum Z position of the printhead, it will keep pushing the printhead down until it can detect the endstop, which will end up with the nozzle crashing into the print bed and creating a scenario where it seems like the bed is way too high.
How to Fix the Issue of Ender 3 (Pro/V2) Bed Being too Low?
Due to there being a couple of different solutions with different outcomes that you can apply to solve the problem at hand, the solution process can take some trial and error depending on how large the gap is and how precisely you follow the solutions.
Our primary recommendation for fixing the issue of your Ender 3’s bed being way too low is to loosen the bolts of the Z limit switch and place it at a lower position compared to where it currently is positioned, which will give the nozzle more room to move down before it trips the endstop and comes to a halt.
A vital point to keep in mind while lowering the endstop position is to do it in tiny increments and test after each increment, as lowering it way too much can cause the nozzle to crash directly into the bed, which can result in severe damage to your Ender 3.
Alternatively, if the leveling knobs under the build plate are compressed, and the distance between the nozzle and the bed isn’t way too significant, you can try to loosen the leveling knobs to push the bed slightly upwards, which might fix your issue without having to modify the endstop positioning.
How to Fix the Issue of Ender 3 (Pro/V2) Bed Being too High?
Similar to the bed of your Ender 3 being too high, there are a couple of distinct solutions with varying difficulties you can attempt to apply to fix the issue of the bed of your Ender 3 being too low, depending on the severity of the problem.
To fix the issue of your Ender 3’s bed being way too high, which causes the nozzle to crash into the bed or scratch it, you will need to do the polar opposite of what you would do if the bed were too low and place then Z endstop at a higher position than it currently is placed.
In this case, we recommend pushing the Z endstop up by a decent margin to remove the risk of the nozzle crashing into the bed again, then positioning it downwards incrementally until the nozzle and the bed have an appropriate distance between them.
Alternatively, if the leveling knobs under the bed are entirely loose, you may be able to introduce some extra space between the nozzle and the bed by tightening the leveling knobs, which might save you from having to re-position the endstops.
Both the bed being positioned too high and too low will prevent your Ender 3 from conducting the printing process correctly, but between the two, the bed being placed too high is definitely the one to be extra careful about due to the damage it can cause to the equipment.
To quickly recap, a Z endstop placed at a position that is either too high or too low in relation to where the print bed is will cause the spacing between the nozzle and the bed to become either too little or too much, creating the scenario of your Ender 3’s bed being too high or too low.
While it’s sometimes possible to quickly resolve the issue by tightening or loosening the bed leveling knobs to compensate for the difference, in most cases, you will need to unscrew the Z endstop and move it to the appropriate position.