Warping is a relatively common problem in the world of 3D printing and usually occurs when the first few layers of a print lose adhesion with the build surface.
This can be caused by a number of factors, including both incorrect printer settings and external factors such as ambient temperature.
When referring to warping this is of course nothing to do with the USS Enterprise travelling at the speed of light, although speed will be a factor as we’ll see later on.
No, warping in 3D printing terms means that the shape and structure of the base to your print has become distorted and warped.
This is only really a problem in FDM printing rather than resin, but can completely ruin a print that may have taken hours to produce.
The first few layers of your print are the ones that set the tone for the success of the overall outcome, and it can be very frustrating when warping happens.
Hopefully, you’ll be able to notice after the first layers have been printed whether warping is occurring, but this isn’t always the case.
Warping can happen once you’re a fair way into your print, and this is often harder to detect as you may not be looking out for the issue at that point.
In this article we’ll be discussing the issue of warping, how it happens and how to prevent it.
We’ll also be looking at ways of repairing warped prints and methods used in post-processing to salvage your print.
Preventative and reactive tips will also be looked at. These will include some things that you may have already tried, but hopefully some new ideas which will be of assistance to you.
Causes of 3D Print Warping
As has already been mentioned, there are a number of reasons why your 3D print may have experienced warping.
Let’s first take a look at those reasons before we move on to how we can prevent them.
Bed Adhesion Issues
Good print bed adhesion is a major bugbear among 3D printing enthusiasts and can be one of the hardest things to get right in the early stages of your 3D printing journey.
Some people have even given up on the hobby completely after many failed attempts to get their print to stick to the bed.
Once you do get things right and your print starts to look like it’s starting to build, the next frustration is the fact that it’s warping and lifting from the bed in some areas.
Warping will start at the edges of the print and this is partly down to the fact that, although you thought you finally had good bed adhesion, you actually only had partial success.
We’ll look later on at how to prevent this, but the major contributing factor in this instance will be the bed adhesion setting in the model’s g-code.
Print Bed Temperature
The temperature of the print bed is important to get right for any print and is a contributing factor to warping.
The temperature you set is determined by the type of filament that you use, and this can also vary between filament brands.
For example, PLA will typically have a print bed temperature of 55-65 °C whereas a filament such as ABS may need it to be 80-100 °C.
Another factor in the temperature will be the type of print bed surface you’re using.
A flexible metal or PEI build plate should work with the temperatures we’ve mentioned, but a tempered glass plate will need a higher heat (70-80 °C) for PLA.
If these temperatures are set incorrectly then the first layer won’t stick to the bed leading ultimately to warping.
Part Geometry and Dimensions
As we’ve alluded to, warping usually occurs to the flat base of models, and this is particularly the case with larger, flat based models.
An example of this may be if you were printing a square, flat based box.
The base of the box may well be big enough to cover the majority of your build plate and therefore have a wide expanse of flat printing.
Having the base of this box perfectly flat is essential to its structural integrity and in turn the ultimate purpose of printing the box in the first place.
Warping may then occur at one or more corners of the base, leading this to continue through the cycle of the print.
You may still find that the sides of the box are still vertical, and the interior is still square, but the base won’t be flat due to warping.
This isn’t limited to just things like boxes and can occur in more geometrically complex models, but again, warping will usually affect the base and the effect will be worsened by the size of that base.
Another major cause of warping is the ambient temperature of your workspace and where your printer is operating.
It’s all very well having the printer set to the correct temperature, but if it’s much lower in the workspace, this may cause temperature fluctuations to your printer.
The print bed may then drop in temperature and cause the print to lift and warp.
Of course, we’re not suggesting that the workspace needs to maintain a temperature of exact equivalence to the print bed, as 50 °C+ room temperatures would be unbearable.
This is more about avoiding cool spots and drafts which can cause sudden temperature drops across the print bed surface.
Other factors that can cause warping are print speeds and layer heights.
If the print speed is too fast then the filament won’t have time to cool and form properly and this will then make the print prone to warping.
Conversely, though, if the speed is too slow for the type of filament being used, it will cool too quickly and again won’t adhere correctly to the print bed.
The layer height can also have a similar effect on the print, as this too can cause issues with premature cooling.
How To Prevent 3D Prints From Warping
As the saying goes, prevention is better than the cure, so there are ways that you can prepare your printer to avoid warping.
Let’s take a look at a few of those preventative measures.
Proper Bed Preparation
As we’ve discussed, getting the print bed temperature right for the type of filament being used is important.
However, there are other things you need to prepare with regard to the print bed.
- Make sure it’s level: This of course is essential in any print scenario, but an unrevealed print bed can stop proper adhesion and prevent the first few layers from printing flat.
- Add an adhesive agent: Some people find adding glue to the print bed helpful with adhesion, and builders’ tape is also an alternative. Adjustments will need to be made to the nozzle height if using the latter, as it will add extra height to the print bed.
Using Supports and Brims
This will again bring us back to print bed adhesion and getting those first layers to stick.
Adding a brim to your print will help with adhesion at the edges, but you may also consider one of the other options available for first layer adhesion.
These would be a skirt, raft, or lace, but not all would be good prevention against warping.
A lace edge will provide little protection against warping, as it’s mainly there to provide a decorative outline round your print.
A raft though may be a good choice, but it too will be prone to warping as it will basically just be adding extra, removable layers at the start of your print.
So, a brim would then be your best option as it connects to the edges of the print but doesn’t go under it in the way a raft does.
A brim will therefore act as an anchor for the edges of your print.
The use of supports is also a good measure against warping, as not only will they hold up the parts of your print that need supporting, they’ll also apply downward pressure to the print.
This will then stop the lower layers from rising and warping.
Slowing Down Print Speed and Decreasing Layer Height
As was looked at in the previous section, slowing down the print speed to the correct level allows for better adhesion and for the layers to form correctly.
The layer height can also be decreased to ensure less filament is being extruded, thus again allowing the layers to cool and form properly.
Proper Bed Temperature Settings
We covered this issue in the previous section, but it’s an important preventative setting to get right and avoid warping.
Remember then to check the recommended bed temperature for your filament type, and also take into account from what type of material your print bed plate is made.
We also mentioned the ambient working temperature for your printer and that cold drafts can have an effect and cause warping.
One way to prevent this would be to either purchase or build your own printer enclosure.
This would then prevent drafts altogether and will increase the temperature surrounding your printer to one closer to the printer itself.
Fixing 3D Print Warping
Of course, it’s inevitable that even after all these precautions, you’re still at some point going to end up with a warped print.
All is not lost though as there are a few ways you can repair and salvage your model.
- Reheat the print: It could be possible to reheat either the whole model or just the affected area and then manipulate it back into shape. Caution should be taken when trying this so as to avoid breaking the print and also potentially burning yourself.
- Applying pressure: This could actually be done mid-print if you notice the warping happening early on. If you have a raft or brim added to your print, you could pause it and add tape or even a small weight to the edges to hold them down. You could also do this once the print has finished, but this would then lead us back to the reheating technique.
- Post processing: This usually means sanding, filling, and painting. But aside from that, it can also include the techniques we’ve mentioned above. If however, those don’t work, you could always resort to filling the area that should have been printed. If we go back to our example of a printed box where the sides were vertical, but the base was warped, it is possible to add filler to the base to make it flat again. This may take a considerable amount of filling and sanding and will add extra weight to the model. But you should then end up with something close to what was intended.
- 3D Pen: A 3D pen is basically a mini portable 3D printer and can heat PLA or ABS filament to the same working temperatures as a full size printer. The pen could be used instead of filler, but in the same way, to fill the void left when the print warped.
So, we’ve seen what can cause warps to your prints and what you need to do to try to prevent it happening in the first place.
These preventative measures are mostly things that you need to be checking anyway before you print, as they may not only affect the issue of warping.
We’ve also discussed some of the ways that you can repair warped prints, and this could save you the hassle of reprinting as well as the cost incurred through wasted filament.
The conclusion therefore is that you can take all the steps necessary to prevent your print from warping, but sometimes it still just happens. The other take-away from this discussion is that, even if you do have a warped print after setting everything correctly, this can still be salvaged using some post-processing techniques.
Let’s then finish by returning to The Bridge of the USS Enterprise and setting the engines to Warp Factor Zero!