Get feedback on your 3D designs! Show off your 3D Models & Prints and receive feedback/comments!
Community rules
1. Be kind and courteous
We're all in this together to create a welcoming environment. Let's treat everyone with respect. Healthy debates are natural, but kindness is required.

2. No hate speech or bullying
Make sure everyone feels safe. Bullying of any kind isn't allowed, and degrading comments about things such as race, religion, culture, sexual orientation, gender or identity will not be tolerated.

3. Only 3D printers advertised.
Only 3D printers or directly related product may be advertised. If you post anything else it will be moderated and you will be banned.

4. Replying to posts
If you reply to a post, make sure your reply is connected with the main topic, do NOT take a topic off track.

5. All post are moderated
Every post on here is moderated - always. Don't bother joining unless you have works to share or problems to inquiry about 3D printers. That is all that will be allowed on this group.
Post Reply
User avatar
Posts: 816
Joined: 2020-06-24 1:56


I promised I’d give you a real-world example, and here it is. Not long ago I made a filament cooling duct to help with an overhang problem I was having. These are the settings I used. On a side note, if you are interested please check out my article about why I made the cooling fan duct.

I hope this helps clarify what we talked about above. If you have any questions I don’t cover below leave them in our comments, please. OK, on with the example.

Back in the main window, you will see the build plate as you defined it, and all the print settings along the right side. I’ll go over some options using my filament cooling duct.



At the top of the settings on the right side of the window, you’ll notice my material is the white Hatchbox PLA I defined, and the color of the model on the virtual print bed matches that. In actuality, since my printer only has one extruder it really doesn’t matter what color Cura says it is, the printer will use the spool I have on it at the time. However, if I had a dual extruder model, the material I had defined for each extruder would matter a lot!

By default, Cura will use the settings defined in the material profile to determine things like nozzle and bed temperature. However, these can be overridden manually or by the print profile you choose. We’ll go over those more in-depth in a couple of sections.


Next, I am using a custom print setup with a draft print profile I set up with a 0.2mm layer height. For most prints, 0.2mm is considered adequate quality. If you go higher the individual layers are more visible and lower the prints can start to take a very long time.



Keep in mind that your printer may have preferred layer heights that are not a simple multiple. For example, because of the Z-axis motor it uses, the Creality Ender 3 gives the best results if it uses layer heights that are a multiple of 0.04mm. It can print at 0.1mm, but it will give more consistent results at 0.08mm or 1.2mm. These types of values are commonly referred to as magic numbers. With a little bit of research, you may find some for your printer as well.


For the shell of my duct, I am using a wall thickness of 0.8mm. That’s two times the diameter of my 0.4mm extruder. Remember the extruder size when you are designing things to print. If you stick with multiples of the extruder diameter when you design and when you select a wall thickness, you will get more consistent results. 3D printers can deal with differing diameters by changing the extrusion speed as it relates to the movement of the nozzle, but if you have a choice, try to stick with simple multiples.


You can do a similar thing for the top and bottom thicknesses, where I am using 0.8mm – exactly four times the chosen layer height.

Do keep the strength of the object in mind when choosing thicknesses. Larger wall thicknesses will be stronger, though there is a point of diminishing returns. Very large values will be strong but will increase cost and print time significantly, so only use them if you know you need that strength. Cura’s default wall thickness for 0.4mm nozzles is 1.2mm, which is a decent choice for most prints.

The 0.8mm value I’ve chosen here is thin enough to be pretty fragile, but I did that on purpose to maximize the space available for airflow. I will have to wait until the bed is completely cool before trying to remove it though, or it will probably break.


The infill setting doesn’t apply to this print (it’s completely hollow). For those new to 3D printing, infill refers to how much material the slicer will use inside solid objects – how filled in it is. I have found that the default 20% infill is fine for most solid objects, but it’s easy to increase it if you need a stronger print or to set to zero if you want to hollow out an object that wasn’t originally designed that way.


Keep in mind, the infill setting affects print time a lot. An object with 100% infill will be very strong but will take far longer to print than the same model at 20%. Also, consider the type of infill you need. Cura provides over a dozen different infill patterns depending on what strength properties are needed. The default Grid setting is fine for an object that may have force exerted downward on it, but if you are printing something that might get pressure on multiple sides, you will want to use a three-dimensional infill, such as Cubic, instead.

Gradual infill steps will tell Cura to reduce the infill density as it gets farther from the top of a model. Specifically, it determines how many times to reduce the infill density by half. Here is how the layers would be divided on a simple cube using one gradual infill step:


The top and bottom are solid, as defined by the Top/Bottom Thickness setting. The selected infill of 20% near the top. Lower on the cube, where strength is less important, Cura halves the infill to 10% based on the specified 1 gradual infill step. If you chose two gradual infill steps, Cura would halve the infill again, to 5%. Exactly where these transitions occur depends on the height of the object.

Post Reply