In 3d printing, the calibration (torture) test is very important. There are 3 scenarios where you will want to perform calibration tests
- When you buy a new 3d printer, you want to test how accurate your 3D Printer is.
- When you use a new filament, you want to test if your 3d printer works well with the new filament.
- When you replace a part of a 3d printer that may affect the quality of the 3d print such as hot-end, extruder…
- You have a complex model and want to find the optimal print setting to get a high-quality 3d print.
There are many different calibration tests, and each test requires a specific print test model. The following in-depth tutorial will help you understand what types of calibration tests need to be performed and along with it, I will provide the most suitable 3d print models (STL file) for each calibration test.
Why you should do calibration tests
- Bridging Test
- Overhang Test
- Dimensional Accuracy Test
- Negative space test
- XYZ Calibration Cube
- Retraction test
- Bed Center Calibration test
- Bed Level Calibration test
- Surface Finish Calibration Test
- Temperature tower test
- Lithophane Calibration Test
- Dual-Extrusion calibration test
- All-in-One 3d printer test
- Wrapping up
What is bridging in 3d printing?
Bridging in 3d printing is the extrusion of material that connects two points horizontally without the underlying support structure (just like a bridge).
Usually, with a short bridge, there is rarely a problem. However, if the distance between two raised points is far apart, sagging, drooping, or gaps between the extruded segments can occur.
If there is a problem with the print in the bridging test, don’t worry too much because usually, the actual prints will not have a large bridge length like in the test print. However, you should still consider tweaking your print settings for better results.
There are 3 important tweaks to improve bridging:
- Increase the cooling (or fan speed)
- Reduce the printing speed
- Reduce the printing temperature
You can refer this video for more detail on how to optimize slicer settings for better 3d printing bridges
Suggested models for bridging test
Bridging test by Walter
|Bridging test by 3dme
What is overhang in 3d printing?
3D print overhangs are shapes that are printed in midair that extends outwards and beyond the previous layer. There’s no support for overhangs, so if you don’t have proper settings or your filament is not appropriate for overhangs => There’s a high risk that your print will be ruined (drooping and curling).
There are many factors that can improve the quality of overhangs
- Increase the cooling fan speed and decrease print speed: a high cooling fan speed and lower print speed will give the melted plastic enough time to solidify before the next layer is extruded
- Make sure the filament is not wet: If the filament is wet, it will easily cause stringing and make the protruding part soft and easy to sink. You can read this detailed tutorial on how to dry filament.
- Lower nozzle temperature: When you lower the nozzle temperature, the plasticizing time is reduced, resulting in less drooping and curling.
- Increase layer height: thicker layers better resist drooping as they have more strength.
This video by Farnz includes many tips for improving 3d printed overhangs
Suggested models for overhangs test
Bridging test by Walter
|Bridging test by 3dme
Dimensional Accuracy Test
Why Dimensional accuracy test is important
The Dimensional Accuracy test allows you to check the accuracy of dimensions of 3d printed objects.
You probably won’t care much about dimensional accuracy if you just 3d print simple objects for entertainment or decoration purposes. However, if you are printing objects that require high precision (eg: an object made of many small parts) => dimensional accuracy is very important to keep things fitting properly
Tolerance for the dimensional accuracy test.
- Greater or less than 0.5 mm is BAD
- 0.2 – 0.5 mm is GOOD
- Less than 0.2 mm is FANTASTIC
If your printer dimensional accuracy test results are not good, you can refer to the following factors to improve your 3d printer’s dimensional accuracy
- Machine Accuracy (resolution)
- Type of printing filament
- Model Size
- Impact of First Layer
- Nozzle: Clogged nozzle, Nozzle size
- Printing Temperature
If you are having problems with Dimensional Accuracy, take a look at this video by Crosslink to learn how to improve dimensional accuracy on your 3D printer:
Suggested models for Dimensional Accuracy Test
FDM printer benchmark by Notebookcheck
|Calibration cross by lukeskymuh
XYZ 20mm Calibration Cube by iDig3Dprinting
|2015 3D Printer Shoot Out Test Models by MAKE
Negative space test
The negative space test is an especially useful test if you often 3d print objects with many small parts and require joining prints or parts together into one assembly. With the small Negative Space tolerance, it’s easy to put the parts together without using too much force.
Imagine you need to 3d print an object like the image below, but your printer has a large Negative Space Tolerance => It will be difficult for you to pull out the bolt.
Suggested models for negative space test
Make: 2017 3D Printer Test Files
|Make: 2015 3D Printer Shoot Out Test Models
XYZ Calibration Cube
This is a simple but essential print test that allows you to test actual model dimensions against the expected dimensions.
This test is performed on a cube with 3 X-Y-Z axes that are exactly 20mm in length. If your printed cube has X, Y, and Z axes that are not 20mm in length (for example 19.5) => you should consider adjusting your e-Steps per mm in your printer’s firmware.
Make sure your bed is properly leveled before printing or you won’t get an accurate result.
Here’s a video by Tom Buck on XYZ Calibration Cube test:
Suggested models for XYZ Calibration Cube test
Dual Color XYZ 20mm Hollow Calibration Cube
|XYZ 20mm Calibration Cube by iDig3Dprinting
The retraction test helps you check the most suitable retraction setting for your 3d printer as well as your filament to reduce stringing.
As you know, the retraction setting is one of the most important settings to combat stringing.
This test helps you find the most suitable retraction setting (including 2 main parameters: retraction speed and retraction distance) to minimize stringing by instructing the nozzle to move through the 4 pointed towers.
If you have a stringing problem, try changing the following parameters through the slicer software to find the most optimal setting:
- Print temperature
- Retraction speed
- Retraction distance
- Prime speed
Also, check to see if your filament is wet or if the printer’s nozzle is clogged. For more details, you can check this instruction on how to fight stringing.
Here’s a very detailed video by Frank about Retraction Calibration
Suggested models for retraction test
Retraction test by deltapenguin
|Randomized Retraction Test (Customizable) by walter
Bed Center Calibration test
Sometimes, your 3d model was printed outside the heat bed print area, especially with large-sized 3d models. The cause of this is that the printer recognizes the wrong center of the heat bed.
The Bed Center Calibration test helps you identify the center of the bed and assists you in changing the bed center to the actual bed center
Here is an example of a 3d printer that wrongly recognizes the center position of the printer bed
If the deviation is not too large, you can use slicer software to re-align the center position. However, if the deviation is large and affects the print, consider repositioning the center of the printer bed immediately.
You will need to interfere with the printer’s firmware to change the bed center. Please refer to the following guide Bed centering with Marlin Firmware 1.1.X from an expert to follow.
Suggested models for bed center calibration test
Bed Center Calibration Tutorial (using parametric crosshairs with square)
|Ender 3 Pro Bed Level Test + Calibration Wizard
Bed Level Calibration test
Bed level is one of the very important factors for a high quality 3d print as it lets the material extrude evenly across the entire build surface.
An uneven or wrapped 3d print bed will lead to some of the following bad consequences
- As the surface is uneven, the filament will not stick evenly on the build plate surface because the first layer does not stick properly to the bed.
- If the distance between the build surface and the nozzle is too small, excess filament will stick around the nozzle and could lead to the print being pulled from the build plate or distorting the print.
- The gap between lines of extruded filament various across the printer bed
Bed Level Calibration test allows you to check if the 3d printer’s build plate is even or not, thereby making the appropriate adjustments to level the build plate.
Here’s a video detailed video by Michael Laws on how to level bed for perfect first layer for beginners.
Suggested models for bed level calibration test
Ender 3 Level Test by elmerohueso
|Bed Level Stripes Test
Surface Finish Calibration Test
Sometimes, you may experience rough print quality when printing curved surfaces.
The most common cases are bulges appearing on curved parts of 3d prints or layers don’t overlap 100%
When facing the above situation, you should perform the Surface Finish Calibration test by printing a shape with a diversity of surfaces to check
This test will test the surface finish in the curved parts of the model by changing parameters such as Infill and Layer Height.
You will find detailed instructions from the author on how to set the print parameters for each test in the description on Thingiverse.
Through tests with different printing parameters, you will find the most suitable setting to apply to your actual prints and get the best results.
Suggested models for Surface Finish Calibration Test
Surface Finish Calibration Test Shape by whpthomas
|Surface Finish Calibration Shot Glass by MkMan
Temperature tower test
The temperature tower test helps you check which printing temperature is best for the filament you are using
Through this quiz, you will understand the impact of different temperatures on the bridging, stringing, and overhangs of your 3d print.
The temperature tower test helps you check which printing temperature is best for the filament you are using. Through this quiz, you will understand the impact of different temperatures on the bridging, stringing, and overhangs of your 3d print.
This test works by printing each block of the tower at a different temperature. Usually, the difference should be about 5-10 degrees Celsius.
To use this test accurately and efficiently, you will need to set the print temperature for each block of the tower through slicer software such as Ultimaker Cura. If the setting is correct, the temperature will change automatically when the print head moves to the next block
You can refer to this video to learn how to configure Cura for the best result on the temperature tower test
By inspecting the tower after printing, you will be able to easily check the optimal temperature for the type of filament you are using. Usually, the optimum temperature will reduce the stringing and increase the strength of the 3d print.
Suggested models for temperature tower test
Smart compact temperature calibration tower by gaaZolee
|Customizable Temperature Calibration Tower by kerog777
Lithophane Calibration Test
If you’re looking to design and print Lithophane with your 3d printer but haven’t found the most optimal setting, this is an extremely useful test that you should take.
As you can see, each block has a different thickness, ranging from 0.5mm up to 7.0mm. Once finished and lighted through lithophane you will see which thickness is best for you.
If you make good use of the Lithophane Calibration Test and find the most optimal setting, you will have a perfect lithophane as shown below.
Suggested models for temperature tower test
Lithophane Calibration / Test by MakerMaveric
|Lithophane Calibration Test 0.4 Nozzle
Dual-Extrusion calibration test
Dual extrusion is the process of 3D printing two filaments with two separate nozzles.
Due to the complexity of dual extrusion printing, if you do not perform calibration tests before performing actual printing, there is a high chance that you will have 1 print with an undesirable result.
The dual-Extrusion calibration test will help you check the printing ability of your dual extruder to avoid problems like stringing, Layer Shifting, Overlap & Oozing.
Suggested models for Dual-Extrusion calibration test
Lattice Cube 3D Printer Torture Test (Overhangs and Dual-Extrusion)
|Dual Extrusion Calibration using Slic3r
All-in-One 3d printer test
In addition to the above separate tests, I also make a list of test models that can help you perform many calibration tests right on 1 print.
All In One 3D Printer test
This is one of the most used calibration tests according to Thingiverse statistics
This test includes multiple test in one model: support test, scale test, overhang test, hole test, diameter test, and bridging test. Print this with 100% Infill without support.
>> Download STL file: https://www.thingiverse.com/thing:2656594
Funky Hollow Calibration Cube
With a size of only about 30mm on each side of the cube, the Funky Hollow Calibration Cube has the advantage of a material-saving print test. This model allows you to perform tests on dimensional accuracy, stringing, retraction and bridging.
Test your 3D printer (3 Versions)
Test your 3D printer is a complex test print including many different tests like Bridging, Stringing, Temperature, Retraction, Dimension accuracy, Overhang tests.
The maker creates a complex design containing many different tests to help you perform an overall test with only one model.
The author also points out common problems and ways to fix them, you can refer to the description for more details.
>> Download STL file:https://www.thingiverse.com/thing:704409
>> Download STL file: https://www.thingiverse.com/thing:1019228
There’re 20 different tests in this version, you can have an quick overview on this picture:
This latest version includes some new test such as: Z-Height Check, Warp Check, Spike Hole in wall, Raft Test, 2 different extrusion widths: 0.48mm & 0.4mm
>> Download STL file: https://www.thingiverse.com/thing:1363023
In addition to helping you make more precise adjustments to your printer, calibration tests are also an effective way to save time and printing materials.
Hopefully the tests listed above along with the stl test model files will help you perform the necessary tests for your 3d printer. All calibration tests are designed to serve a specific purpose, so if you have time, you should try them all to get your printer perform at its best.
If you feel there are any necessary tests missing from the above list, please leave a comment in the comments section. I will gladly add them to the list if they are relevant and useful
Very nice list for 3d print calibration test. Thanks for sharing!