Advanced Delta Printer Calibration (tower position + individual diagonal rod) by dolpin

Last crawled date: 2 years, 12 months ago

This calibration object will help you to calibrate angle and size errors on your delta 3d printer
These errors are typically caused by tower position errors and different diagonal rod lengths.
This calibration object will show if your printer suffers from sizing and angle errors and the instructions will help to solve these errors.
My Achatz easyDelta printer had a 1 degree error in angles and over 1mm error in sizing in certain directions. This is caused by the towers not being positioned at a perfect 120 degree angle around the center, and small individual size errors between the rods.
First errors must be fixed on the printer itself, but on some printers this might not be possible.
I used a jig to glue the joints to the diagonal rods, but small errors (1/10 mm) result in bigger errors in the print.
The basic delta printer calibration steps are:
calibrate the print bed on each tower position by adjusting the z-height for each carriage
correct for bowl/dome shape by adjusting the DELTA_RADIUS parameter
tune the print size by adjusting the DIAGONAL_ROD parameter
After the basic calibration you might experience that the actual print is not equal sized in all directions and the angles in all directions are not as they should be. Resulting in for instance trapezoid objects instead of square-angle objects.
The next calibration step is to detect these errors and calibrate your printer.
These errors are typically caused by tower misplacement and differences in diagonal rod length.
After calibrating the tower angles and individual diagonal rod lengths using the marlin firmware, I managed to achieve 0 degree angle error and a maximum of 0.1 mm size error in any direction in the print !
The calibration object is printed after the basic calibration. Print out the calibration sheet and use this sheet to measure the angles between the X-Y-Z towers. Use a slide caliper to measure the print size in the X-Y-Z tower direction and calibrate your printer in the Marlin firmware.
Check the instructions for the calibration steps and how to correct this.