Why won't my print stick to the bed?

It could be that your print doesn't stick to your bed for different reasons. The result? A 3D print that flies off in all directions, or just prints completely wrong. In this post we will have the most common reasons

Your bed is not leveled

One of the most common causes of bad adhesion is that your bed is not leveled. If your bed is tilted then the distance between the nozzle and your bed is not the same height on all places. This means that in some spots the nozzle is too far away, and some spots maybe too close. Which causes the filament to not be pressed properly onto your print, or on the surface. So make sure your print bed is leveled!

The nozzle is too far from the bed

Similar to having a bed that is not level. If your nozzle is too far from the bed, your filament is not being pressed properly onto the surface. Instead of the first layer being nicely flat, it will be placed on your bed as a loose thread. Then it let's go to soon of course, and you will have no adhesion. You could see this because the first layer is rough and grainy with loose threads and gaps between them. The lines are more round instead of flattened. You could adjust this with Z-offset in your slicer OR 3D Printer settings.

The bed is dirty

A dirty bed secretly causes a lot of adhesion problems. Even a thin layer of grease you could not see ( from fingers for example ) could already cause you to have bad adhesion. Filament really only sticks to a clean surface, not to dirt or grease. Every time you touch your bed with your finger, you make it a little bit greasier, even though you don't see it. Besides that, dust or leftover pieces from old prints could also be a culprit. Often you can clean your bed again with isopropyl alcohol, spray or dab a little bit on it and wipe your bed thoroughly. And let it dry properly! Watch out, don't touch your bed again. Sometimes you read that you can also use dish soap, however this is not recommended. Dish soap could cause a little bit of residue to stay behind, despite rinsing it off well. This causes your print bed to stick worse and worse over time.

The bed temperature is wrong

Your bed temperature is an important part of adhesion. Too cold and your filament cools down too fast and pulls loose. Too warm and your filament stays too soft, which causes the first layer to deform. Every filament has its own bed temperature, but for PLA it is usually between 50°C and 60°C. For PETG this is around 70-85°C, ABS 90-100°C and TPU 40-60°C.

You're printing too fast on the first layer

Your print speed is something people tend to overlook, but it does have an influence on your adhesion. If you print too fast the filament just doesn't have the time to stick properly. So it can be a good idea to print your first layer just a little bit slower. If you for example normally print your first layer at 60mm/s, you could try to print your first layer at 20mm/s or 30mm/s. In Orca slicer you can set this with "First Layer Speed".

Give it a try!

You need a brim or raft

Sometimes the problem is not the adhesion of the filament, but how much your 3D print is in contact with the bed. For example with small or narrow prints there is too little "surface" to stick your print properly. If this is the case, try adding a brim or a raft.

Brim

A brim is a flat edge of extra material that is printed around the outside of your print, on the bed. This creates a bigger contact surface, and keeps your print sitting better.

Raft

A raft is a thick grid of material that is First printed on your bed, and on top of that comes your own print. It is more rough than a brim, and is mainly used with for example ABS, since these have more issues with warping. In general a brim is good to start with and see if it works.

Cold environment or draft?

Make sure your 3D printer is not in a cold environment. This can cause your 3D print to cool down too fast and not stick properly to the bed anymore, mainly with materials like ABS and ASA. An open 3D printer is extra sensitive to this. With a closed enclosure this is easier, because it keeps the warmth inside and protects against draft for example. If draft is a problem, you could put a cardboard box around your printer to keep the draft out. When it is cold, maybe a different moment to print is a better idea. At least close your windows and doors.