If you spend any time reading through 3d printer help forums, it won’t be long before you see someone post about a problem that they are experiencing, to which someone else replies “you need to level your bed better.” But how good is good enough?

When it comes to 3d printer beds, I typically run into two variations:

• 5 point bed level. This is a bed configuration that comes standard with many different firmware packages. It’s simple to set up and will give you pretty good results. The downside is that it doesn’t provide any flexibility in case your bed is warped in between the points. In doing some testing on this version, it seems like I started to have problems if my bed variance exceeded 0.05mm. Increasing my first layer height somewhat mitigated the problem, but didn’t solve it completely.
• Mesh bed level. For this experiment, I used a 25 point (5×5 grid) mesh bed level. I allowed my bed variance to get close to twice my layer height, so for a 0.1mm layer height my bed variance was nearly 0.2mm. Then I set up my mesh bed level. I was able to see a slight difference in print quality near the base as the bed variance was increased, but it wasn’t significant. However, the differences that I observed were pretty minor and I believe that, in most cases, the resulting print would be considered “fit for use.”

Here is my recommendation. Get your bed as physically flat as you possibly can. See if you can get it to 0.05mm flatness. In most cases, this is possible as long as you have decent springs holding the bed up. Then run a mesh bed level to compensate for the variance that still exists. For most materials, I’m able to run prints without any hairspray, glue, tape, or anything else to hold the print onto the bed by following this methodology.