3D Print 101

Prevent Warping with Draft Shields in Cura?

por Kingroon 3D en Apr 29, 2022

3d printing is no stranger to a spool of filament. They come in a massive range of colors, some of them are chopped with other additives to give them unique looks or unique properties. And there's really a lot of options out there depending on what your specific use case is. With all these share in common and that's that they are of plastic that are moldable at a certain temperature and they solidify when they are cooled. And it's this for 3d printing. However, it's during these heating and cooling cycles that these materials will expand and then contract with. Some of them doing it more than others and it's a huge contributor to warping, which is something that anybody that 3d prints is familiar with.

3D Print Filament Shrinkage

thermoplastics, they all have their own

factors including processing method. ABS has a higher shrinkage rate than PLA, which is one of the reasons it's recommended to print inside of an enclosure. Enclosure will allow it to maintain a more uniform heat and have it shrink together, versus having it cool section by section as the hot end gets further and further away, which can cause things like splintering or warping. Due to this, I would never recommend printing ABS without an enclosure. But that's exactly what we're gonna do today.

For my testing, I started off with a motor mount that i had downloaded for the Voron switch wire, and all the parts are printed out in build series ABS on the Aquila S2 3D printer. I went with 105 celsius on the bed, and 255 celsius on the hot end. The 255 celsius on the hot end is a bit warmer than I would typically print ABS. I decided to go a little bit warmer, because again we are not using an enclosure while the part was printing.

I plugged in the ir camera to get some videos as well as some photos. One thing that i found that was really interesting was just how hot the base of the part was butting up against the bed. Now i expected it to be fairly warm but it was as warm as filament that had just been extruded out of the nozzle just a few moments ago.

printer is in is fairly tight and the temperature throughout this condo has been in the mid to even upper 70s. So it is fairly warm which is also not hurting its ability to maintain that heat.

After the part was printed i was ready to apply a draft shield in Cura. Draft shields are not visible by default. We'll need to head over to the hamburger menu in the print settings toolbar and go to "Manage Setting Visibility"

settings.

What is a draft shield?

as a wall around your model that traps hot air in and shields from external airflow. If you're familiar with skirt in Cura, picture a skirt but one that goes up much higher than just the first layer.

With the two photos side by side, I could see the impact the draft shield had. Having the thermal camera set to the exact same range for all the prints, the parts in the draft shield stayed much warmer throughout the entire print.

Looking at the draft shield, you supposed to. As the outside of it is cooler, keeping some of the draft away from the part. and the heated part is able to maintain some additional heat.

After those first two prints, I ran a series of additional prints. I took a

small fan and i put it on high and one foot away roughly from the printer. the window that's next to the room through.

My goal with that was to see if having that airflow we would be able to see any sort of temperature changes in the abs with or camera.

to be 40mm tall in hopes that

Once the cube got to about 30mm in height, i was able to notice some temperature difference within the cube. Although i didn't notice any warping when the part was printing or when i took it off, there was a pretty big bulge around the 15mm mark.

I then went ahead and printed the exact same cube with all the same settings but with a draft shield. side, you can definitely see that the cube stayed much warmer.

When i put the prints side by side i can see a slight slight bulge, maybe around the 15mm mark. but it is very very minimal compared to the part that did not have the draft shield at all.

Prior to playing around these draft shields over the past week or so, here i

draft shields are something that are super commonly used. But if anybody does or has used them let me know what's your thoughts or what your feedback.