BackLash Test
This is a method for quickly getting a good backlash calibration on your 3D printer. You just zero out the backlash compensation in the software. Then print the objects, Read the correct value and enter it as your new backlash compensation and be done with it.
The files should work for all 3D printers of the Cartesian type. It will not work for delta printers.
Source : https://www.thingiverse.com/thing:4594731
Author : Tillmann Krauss
- Nozzle Size : 0.4
- Layer Height : 0.2
- Initial Layer Height : 0.2
- Line Width : 0.4
Print times : 10 min
Before getting started on this, you need to make sure your print bed is clean and very well calibrated. The print is just a single layer and it needs to be printed just right across the entire surface. You can find more information about bed leveling below.
Before starting the first print make sure to set backlash compensation to zero. Make a note of the old values in case you need to go back. Watch the print start and remove the extra filament that is extruded in the beginning. It is just to prime the nozzle. The included files will make 200 samples. You have to study these samples very very carefully. You have to find the sample with the highest possible value that does not curve. We are talking about a curve that only moves 0.01 mm to the side. It sounds impossible to spot. But it is actually doable. I recommend having a ruler in one hand and a flashlight in the other. You can also use a magnifying glass or take a good quality picture and then zoom in. When you have located the correct sample, calculate the backlash value using the chart/picture above. I think it is a good idea to make three prints and take the average value spotted for each. If one of them is way off disregard it and make another. If in doubt choose the lower value. Repeat for the other axis and enter the values you found in your printer software.
For this backlash calibration methode, we are searching for the pattern right before the first opening "eye"
Connected strings cound +0.01mm for every segment (+0 to +0.09). Each column is +0.1mm for every column (0.1 to 0.9). Backlash is the sum of both, e.g. 0.06 + 0.3 = 0.36mm backlash.
Maximum adjusted backlash with this pattern is 0.99mm. If your backlash is higher, you can easily adjust the Backlashstartvalue in the SCAD script.
Very important notice: In order for this print to work you print bed must be very precisely calibrated. Otherwise the print will come off the bed