Print failures on FDM filament printers are most likely due to poor bed leveling with the printer. I purchased a used Ender 3 from a friend of mine (who took great care of it), but when I got home, I needed to level it. I tried the usual methods, and still failed over and over again. I was getting frustrated.
To level an Ender 3, you must home the print head, then move the print head to each corner. Use a piece of paper under the print head to test the gap between the print head and the bed. Adjust using the turn wheels under the print bed, one per corner. Looking down on the wheels, turn clockwise to raise the bed (to make the grip on the paper tighter) and counter-clockwise to lower the bed (to make the grip on the paper looser).
Leveling can make or break your prints. Get it right and you’ll have good results (most likely) with your printer. It can be tricky, though, but there are some aids that can help you get it right.
The Basic Technique to Level Your Ender 3’s Print Bed
As I mentioned above, you’ll want to test each corner of the print bed. You’re testing to see what the distance between the extruder end and the print bed is. Ideally, it’s about the distance of a piece of paper above the print bed.
- Home the print head
- Manually move the print bed and head to the front, left corner (in about an inch from both edges)
- Try to slide a piece of paper between the print bed and the extruder nozzle.
- If it’s loose, raise the print bed in that corner using the screw wheel below the bed by turning clockwise.
- If it’s too tight or it won’t fit at all, lower the print bed in that corner using the screw wheel by turning counterclockwise.
- Once the paper can move between the two, but you feel some friction (but the paper doesn’t bunch up when you push it), then you’ve got the right amount of tension.
- Move to the next corner and repeat.
- After all four corners, do the whole process again. Moving one corner can move the other corners, so if you’ve moved one, you’ll have to go around again. You can quit once you’ve gone around and not had to adjust any of the corners.
- You are ready to print!
The Assisted Technique to Level Your Ender 3’s Print Bed
Chuck Hellebuyck created a couple of programs that will help you with the manual process. You’ll essentially do the exact same process as above, but instead of you moving the print head, the program will do that for you. To run the program, add it to your SD card, and then select it and “print from SD card” in the printer controls.
The program will first home the print head, then rise up, move to the first corner, then lower. Adjust that corner. Hit the printer’s button and it will move to the next corner. Follow the process.
The program will go around twice, and go to the center. You can test the center, but there’s no adjustments done in the center. There is no wheel there. If you’re still adjusting on the second pass, restart the program and do it again.
Once you’re happy with the homing, print from the SD card again, but this time select the Squares STL file. This time, the printer will start printing concentric squares. It starts in the middle with a small square, then draws ever larger squares. If you find any printing issues, you can adjust the print bed (usually closer to the extruder head by turning the wheel clockwise).
If your finger can go over the squares without any of them being loose, then you’re set. If not, adjust where the square is not adhering correctly (adjust no more than a quarter turn at this point) and clear the print bed of printed material. Print again and continue testing.
I find this method the only one that’s worked for me. First, the paper at the corners, then printing squares until I get the adjustments just right.
- Download Chuck Hellebuyck’s files from Thingiverse at: https://www.thingiverse.com/thing:3235018.
I still print my files with a brim to help adhere the edges down to the print bed, but this has improved my prints dramatically.
Does The Paper Thickness Matter When Leveling Your Print Bed?
Yes it does. I started leveling using a business card that I found lying around my desk. It turned out to be too thick and sturdy. Part of the testing of how far the extruder is from the print bed is to see if you feel resistance on the paper as you move it back and forth under the extruder. If the paper buckles, the resistance is too high, and the card of the business card was just too sturdy for this test.
I then tried standard photocopy paper. This was fine for the first passes. It is thin enough and it has the ability to buckle should you push on the paper and there’s too much resistance (in other words, the extruder is too close to the print bed). For many people, this is good enough. Move to the printing of squares and manually adjust from there.
Some recommend tuning even farther with a thinner piece of wax paper (or sticker backing paper). The thinner paper is perfect for the bed leveling, and takes you to a very good level. Again, once you’re done, print squares until you’re satisfied, then off you to and print something useful!
How Often Do You Need To Level Your Print Bed?
Bed leveling should be done every once in a while. How often depends on what your environment has going on. Here’s a handy table showing some of the triggers to level your print bed.
|Have you moved your printer?||Fully level the bed|
|Have you bumped your printer hard?||Fully level the bed|
|Have you printed six prints without leveling?||Print squares and adjust|
|Do you have pets or children around (and you’re not sure if the printer was touched since the last time you were around it?||Print squares and adjust|
|Has the printer stood for more than a month unused?||Print squares and adjust|
Fully leveling the bed means to take your trusty piece of paper and test all the corners, adjusting, then print squares and adjust even further. Print squares and adjust means to only print the squares, and adjust manually. If you find that printing squares is not working well, back up and go back to fully level the bed with a piece of paper.
Is An Auto-Bed-Leveling Device A Good Accessory For An Ender 3?
I tried the EZABL from TH3D Studio and had a host of issues. The Ender 3 doesn’t make it easy. They never included a boot loader on their onboard control board. What that means is that you’ll have to give it one! You need to purchase (also from TH3D Studio) an Arduino board and the necessary cables to connect it to the printer’s control board. Then, you load some software across to the printer. Then you can upload the software to interface with the EZABL sensing device.
TH3D Studio has it all, and I received it all in a nicely wrapped package. My issue came when I needed to load the software from my computer to the Arduino, which will then load it onto the printer’s control board. The Arduino just wouldn’t play nicely, and wouldn’t fully boot. I tried TH3D Studio’s support chat, but their support is only available Monday through Friday, 8amto 5pm. Not surprisingly, I also work Monday through Friday, 8am to 5pm. So, at an impasse, I sent it back.
This kit, much like the other kits available, is not geared towards the casual 3d printer user. As painful as the process of manually leveling the print bed is, it’s likely acceptable to most people. The whole kit cost just under $100.00USD, and that’s to enhance a $170.00USD printer. Likely, if you’ve got an Ender 3 printer, you’re either a beginner or price conscious. If you’re a beginner, learning to level the bed consistently with the manual tools is a useful skill to have. If you’re price conscious, adding 40% to the cost of your printer to avoid some effort is not a good exchange for your time and money. Stick to manual bed leveling and get good at it, or opt for a printer with a built-in bed leveler, like the excellent $1000.00 Prusa i3 Mk3S.
How do I clean a print bed?
You can clean a print bed with either a little (very little) soap and water, or with isopropyl alcohol. Wipe down the surface using circular motions. The alcohol is a good solution for removing finger oils, the scourge of your prints sticking down.
How do I remove glue from a print bed?
You can first scrape the print bed with a plastic spatula (don’t use a metal one, as you may damage the bed). Once the major residue is removed, go over the surface with isopropyl alcohol. Wipe down the surface using circular motions. If you’re going to reapply glue to the surface, don’t worry too much about completely removing all of the residue. Removing most, however, is a very good practice.