Why do my 3D prints curl and lift?
One of the most common problems for people starting out with their first 3D prints is getting the print to ‘stick’
to the build platform. Often you can’t even get the print to start correctly and you will be left with a ball of
spaghetti. Other times you will get the print to start OK, but after a while the bottom of the print starts to curl
and lift from the build platform. Eventually curling so badly, that the print gets knocked from its original position
and you end up with a print where the bottom half is curled and twisted, while the top is a ball of spaghetti.
what you can do in case of warping/ lifting.
There are, however, additional measures you can take to specifically prevent lifting. Lifting occurs most often at
sharp corners and at large surface areas. If possible, incorporate chamfers, fillets, and rounds in your designs to
lessen the strain on corners which in turn reduces the chance of lifting. Another method is to attach small, one-
layer-thick circles around corners. This increases the surface area of the corners, allowing them to adhere to the
bed better and resist lifting. To apply this technique to your entire print, you can simply add a "brim" to your
model in your slicer settings under skirt and brim.
Removing excess material within your model will reduce the amount of pull on the outer surface, reducing
deformities. Reducing the infill also provides similar results.
Remember when dealing with heat or introducing modifications to your printer, always babysit your machine for
the first few print jobs. It would be a mistake to leave your printer unattended without verifying that your
modifications are working safely and effectively. Furthermore, you should be there to turn off the printer in case
something goes awry.
When objects lift off of the bed you will notice a portion of the print sticking well and others with a gap between
the build surface and the object. This problem is most closely related to problems with prints not sticking at all.
Both problems can be resolved by following the same set of procedures.
to solve lifting problem first thing to make sure object is stick on bed properly with hot bed
Print slower. Printing slower allows finer detail, better adhesion to the build surface and lower layers, and gives
the printed part more time to cool evenly.
ABS and PLA seem to stick really well to hot or warm Kapton tape.
ABS filaments tend to warp much more then PLA. If you are a user who seems to be plagued by the most stubborn
of warping issues, even after following these tips, you may want to use PLA instead.
Lifting/warping is an inherent issue due to thermal shrinkage of ABS plastic ( PLA is less likely have lifting
problem). All FDM style 3D Printers specially that use ABS have this challenge.
The following tips may help:
Make sure the platform is completely level to the nozzle - this can be a challenge to get it level, but it alleviates
the warping. Under the platform you should find three / four screws (with springs on some models), use these to
level the platform to the nozzle.
For large prints, the platform must be hot to every corner, typically pre-heating for half an hour is enough, or
printing immediately after another print.
In the maintenance window, the software reports the platform temperature of the centre of the table, not the
corners! These corners need to be hot! Make sure the reported temperature for ABS is ~105°C for 5 minutes
Create Wind Barrier if you have one - Make sure this is closed during printing, or at least until the raft has been
laid, then it may be opened. We don't want the material being deposited onto the hot platform to be cooled from
above and heated from below creating uneven thermal shrinkage. so enclosure is helping to reduce warping
Draughts/Cool air - This can accelerate uneven thermal shrinkage. The most effective solution here is to enclose
the printer in a suitable box. The box must not be removed once printing begins as it would be like opening the
oven while cooking a souffle.
Nozzle Distance - It is very important to have the nozzle close to the platform (0.1 - 0.2mm), too high and you'll
get the raft lifting. Make sure the first layer of the raft is squished out flat.
if you have Perfboard - We find that the perf board is the best platform for ABS prints. Make sure it is affixed to
the platform properly if yo have one or if you can create one.
Do not - wrench, pull or grab the finished printed models of the platform - doing so will affect the level of the
platform and you'll have to re-level again! Always remove the platform or unclippe the perfboard.
The UP further minimizes this issue by the use of a heated platform & the perforated build boards. ABS has
around a 3% shrinkage but 90% or the shrinkage happens below 60 degrees . The bed on the UP 2 keeps the
model warm until it is finished & the model can shrink uniformly. The shrinkage is taken into account by the
software so the model is printed very slightly oversize.
The Geometry, density & size of each model can also dramatically alter the effects of shrinkage.
If you are getting the dimples but not out on the corners of the model it is likely to be shrinkage.
The other cause of Lifting that is not related to shrinkage can be the nozzle height is set too low, ie The 1st layer
is not getting pushed into the holes of the perfboard (if you have one) so as to give a good hold. You can check
this by looking at the bottom of the raft after it has been removed from the board. If you can see/feel very small
or no dimples at all (that are not broken off) then it may be too low. You should have either 0.5 to 1mm dimples or
marks to indicate they have broken off in the board. You do not need to clean these broken off bits from the
board as the next print can bind to them.
Some users may experience objects becoming distorted in shape as it is being printed. This can manifest itself in
different ways: lifting off of the bed, shell layer shrinkage, and "waving." All of these issues are derived from one
primary cause, the filament is cooling too quickly as the object is being printed.
When shell layer shrinkage occurs when the infill cools as the shell layers are being printed. This is because as
the infill cools, it contracts thereby slightly pulling in the outer layers of your object. You will notice the object
looks like it is caving in on itself slightly.
Shell layer shrinkage
To remedy this you will want to introduce an enclosure to trap heat inside the print cabin (insulate).
Reducing the infill can also reduce the chance of deformities. Because there is less plastic on the inside of your
object, there is less force pulling on the outer shell.
Waving is related to shell layer shrinkage and can be corrected the same way, by introducing an enclosure. You
will notice waving when portions of a print warp similarly to a piece of wood. This most commonly happens to
objects that are long and slender such as a printed butter knife or clothes pins. Add an enclosure or place a
space heater near your printer to keep as much ambient heat near your print as possible wil help lot
shell layer shrinkage
shell layer shrinkage occurs when the infill cools as the shell layers are being printed. This is because as the infill
cools, it contracts thereby slightly pulling in the outer layers of your object. You will notice the object looks like it
is caving in on itself slightly..
Add a ‘raft’
Another way to get a better stick between your print and the build platform is to increase the surface area of the
base of the print. The bigger area where your print contacts the build platform, the better it will stick. Increasing
the the size of the base of your print is done by adding a raft, a thin platform that your print rides on.
Many G-code generators can generate a raft for you, alternatively you could manually add the raft to your model
in your favourite 3D modelling software.
We found that not all PLA is equal. Like good food, good 3D prints require good ingredients! If you are having
problems with your current plastic, try getting some from another vendor. printing reliability an be achieved with
high quality filaments
Blue painters tape
Cheap blue painters tape can be found at almost every hardware store near you. It has a slightly rough surface
and soaks up a tiny amount of molten plastic. Adding a layer of blue painters tape to your build platform will solve
most curling and lifting problems with small to medium sized prints. you can still ran into issues with very large
and time consuming prints, but everything that printed under an hour or two so seemed to come out alright.
Install a heated build platform if you do not have one.
How can you avoid prints from curling, lifting and going crazy? you can use a heated build platform sandwiched
between a layer of sandblasted glass and plywood.
Have a sandblasted glass heated build platform, and still having troubles? First thing to try is a bit of Kapton tape.
When heated it works better than painters tape (especially if you are printing with ABS). Kapton tape is pretty
interesting stuff and was even used all over the lunar lander in the apollo missions.
The final trick worth a shot, is using a bit of hairspray or glue stick on the build platform best it will work on hot
bed. (Glue may not work well on cold bed so you need to wait to get warm. sanding a Kapton tape build surface
will increase the surface area, making it easier for the molten plastic to stick.
ABS surface. painting the build surface with liquid ABS This is has the same effect of laying down a big flat raft.
to make ABS Liquid you can dissolved ABS Pieces of plastic in acetone or ABS glue
Some non technical solutions:
printing on a piece of 1/4″ plywood on top of the heated platform. Then when the raft is done, pause the 3D
Printer then melt the perimeter of the raft to the plywood with a long tipped hot solder iron or hot air gun and
use flat tool to press the plastic. That holds the raft solid tight to the plywood.
Clean your platform with acetone before and after each print.
You can print PLA on a cold platform if you use a good hairdressing spray, the extra strong stuff, on the glass. It
also helps on a warm platform and with ABS.
If you have thin structures or very small layers, print a column next to the object to give it time to cool off.
keep glass very clean, with alcohol.
by using two kinds of hairspray. Coat with Aussie brand “instant freeze” max hold hairspray. To do this, spray a
paper towel with the hairspray then wipe it on the Bed/perfboard (the first layer of hairspray keeps painters’ tape
from peeling up off the board on larger prints). Next, apply the blue painters’ tape. then use Suave brand, max
hold hairspray and coat the tape in the same way.
This technique for adhesion is a little different than most. spray a light coat of adhesive spray onto the build
platform and put a sheet of 100% Cotton, 32 lb resume paper ( South worth ) on the platform. The first layer tends
to soak into the cotton which is held down by the adhesive spray ( the desired amount of adhesion can be
adjusted by the amount of spray used ). The entire print is then easily removed from the build platform. The
paper layer can usually be removed with sandpaper or it can be soaked in water to remove. The adhesive spray
typically lasts for about a dozen or so changes of paper. use small amounts of mineral spirits to remove the
adhesive coating when it builds up.
Some other things that appear to reduce curling:
– Increasing the temperature ( 5 degree increments )
– Turning off the filament fan
– A large clear plastic trash bag over the printer kills any drafts while still giving the print head freedom to move.
Sanding glass / aluminium/bed or kapton tape sanding and then apply glue can also help lifting problems.
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