One of the common frustrations every 3d printer operator have experienced is poor adhesion on 3d printer bed. I know the feeling.., create a model, load your 3d printer, get all excited and BOOM – failed 3d print.
We all know what happened but not always do we know how to keep it from happening again. So here are some tips on how to fix poor bed adhesion and have fun 3d printing.
Why is my 3D print not sticking to the bed?
Most common reason for 3d prints not sticking to bed is the hot end nozzle being too close or too far from the bed. However, if the bed leveling is done correctly with nozzle set at the correct distance and the problem remains. The best fix is the purple glue stick. Read below to find out why so.
When 3d print is not sticking to the bed or print plate, first thing to do is to check the distance of the hot end nozzle from the bed.
If the nozzle is too close to build plate this can damage both nozzle and the plate. It can also cause the clog in the nozzle.
If the nozzle is too far from the build plate it will actually dispense the filament but not infuse it to the build plate. The filament actually cools before it reaches the bed and with no pressure down on it, it just lays over the bed freely and can be moved away if you disturb it.
Both cases will result in a failed 3d prints. To assure your bed is leveled properly see the video below on how to level print bed and set the nozzle distance correctly.
Nozzle distance set Correctly and part still does not stick.
Thankfully there is a remedy for this as well. The first thing to do is to wipe clean hot end nozzle and wipe clean build plate with isopropyl alcohol to wipe away any build up or grease from the build plate.
Then, lowering the speed of first layer by 50 percent and possibly adding a brim would increase the chances of success tremendously.
A Brim in 3d printing is special type of skirt that is actually attached to the edges of your model similar to the brim of a hat. Commonly, the brim is printed with a increased number of outlines to create a large ring around printed part that is easily broken off after 3d print is finished,
First several layers printed good, then corners peel off and 3d part warps.
Just when I thought I got this right after following thru all of the steps above, I get my first few layers perfect. I left my 3d printer printing and went for a coffee break. Upon returning I find that the part is still on the build plate but all of the corners lifted off the bed as my PLA part warped. So, the print was canceled.
Examples of PLA not sticking to heat build plate and warping.
5 steps to prevent 3d part from warping or corners from lifting off the build plate:
- Apply thin layer of glue stick to build plate (bed) or
- Apply blue tape over build plate, or
- Use Raft
- Most significant, improve g-code.
- Increase nozzle and bed temperature above normal printing temperature by 20 percent for layer 1. Cooling fan 50 percent.
- Reduce nozzle and bed temperature from layer 1 by 10 percent for layer 2. Cooling fan 75 percent.
- Reduce nozzle and bed temperature from layer 2 by 10 percent (back to normal) for layer 3 and above. Cooling fan 100 percent.
- Add enclosure to your printer (This works 90% of time)
Tip: Avoid sharp corners if at all possible when designing the model.
Why do printed parts warp?
The reason for 3d printed parts warping is the temperature. Uneven heating or cooling will apply different levels of stress to different areas of part and layers. Because of this corners begin peeling off the bed and rolling up while printer continues to print. If the 3d print was not canceled, finished part will appear to be warped.
Using rafts with your 3d prints could be a game changer. It is for me. I personally love rafts for several reasons.
One, it allows for a slight variation in bed leveling.
Two, it is super easy to remove from the build plate, and three, the space between the lines of filament allows for the filament to cool more evenly which in turn helps to prevent part warping and corners peeling.
Downside of raft is that sometimes it could be quite difficult to separate 3d printed model from the raft. The distance of the model from the raft must be set just right for your particular 3d printer.
What is a Raft?
A Raft is a several layers of material that is printed underneath 3d printed model that form a detachable base. A 3D printed model will be printed on top of this raft, instead of directly on the build plate. Raft are often used to prevent part warping and corners peeling as it usually has a better adhesion to build plate.
How Many Layers Needed for Raft?
3D printed model will be printed on top of these layers. By default most slicers will have these setting preset at three top layers and two base layers.
Raft Base Layers – are the extra-thick layers at the very bottom of the raft. These layers are printed slow and thick to ensure a strong bond to the build platform.
The setting that I found very useful for the raft are three top layer for a very smooth surface to build on. One or two base layers depending on size of the print.
For large surface area it would be beneficial to to two base layers as this will make the raft taller and allow better airflow for even cooling to prevent warping.
Three mm raft offset from part is a good number as it will sickout far enough to easily break away when 3d model is finished printing, and for separation distance between the top layer of raft and first bottom layer of part is 0.14mm when using a standard 0.4mm hot end nozzle on FDM 3d printers.
When Should I Use Rafts?
Usage of rafts may not be an ideal solution to every model you 3d print. As it is a throw away material that is wasted along with time it requires to print it.
Get the most benefits out of the raft when 3d printing very large objects or when working with a high temperature filaments like ABS.
Smaller models may not need rafts to achieve a desired results.
I hope that this post saved you a lot of headache, time, and filament. If you found this content helpful please share with others and subscribe so you don’t miss out on my latest post. Please like, comment below and share with us your 3D printing experience.
Happy 3d printing!