Multi-Angle Test Tower for Calibrating Jerk

This test tower can be used for calibrating Jerk/Junction Deviation

3D printer parts and enhancements

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    Description

    This test tower can be used to calibrate Jerk/Junction Deviation settings for 3D Printers. The Jerk setting causes the printer will slow down more when printing tighter angles.

    This tower has 10 steps - every 3 mm in height there is a slight bump in or out of.08mm. It has angles: 20, 30, 40, 50, 60, 70, 80, 90, 100, and 140 degrees.

    Use the following in order to customize this model for calibrating your printer (requires editing of the gcode file - but I will tell you how!). This example is for Marlin firmware, but you can check which gcode to use on Reprap.org. Link below.

    • First slice the STL with 1 perimeter, no infill, and no top layers - in other words: as a single walled object, and do not use z lift.

    • Decide what your starting Jerk value will be, and how much you want to increment it for each section. You could start with a value lower than the current value in your firmware. (Once again: the lower the value, the slower the printer will move at the corners.)

    • Edit the gcode file with Notepad, look for the layer changes (G0 Z... or G1 Z.... commands), and insert a M205 command to change the Jerk value before the first layer, and every 3 mm. Another easy way to identify layer changes is to turn on the output of comments in your slicer, and the layer number will be included.
      If you sliced at 0.2mm layers then you will insert a line of gcode every 15 layers.

    • Example Jerk Gcode for Marlin: M205 X10 Z5 ; Sets X/Y Jerk to 10mms, Z jerk to 5mms

    • (The text after the semicolon is a comment.)

    • At each Z height increment, insert the M205 with an increased X value. For instance the next command could be: M205 X15 Z5

    • Save and Print.

    • Observe the changes at the corners (blobbing or over extrusion), and changes in any ringing artifacts (these look like waves that happen just after a corner).

    • Count the steps from the bottom for best looking area you observe to determine which Jerk value you used.

    • Either add a M205 command with that Jerk value to your start gcode, or update your firmware with it.

    • You may want to test again with a different default acceleration.

    You can use the same method for testing Acceleration, temperature etc. Just switch out the gcode you have added at each height.

    The gcode setting for Jerk varies by firmware type. See here: http://reprap.org/wiki/G-code#M205:_Advanced_settings

    "Jerk" is called "Junction Deviation" in other firmware and is calculated differently, and so has different setting/values.

    Materials and methods

    A 3D printer's Jerk/Junction Deviation setting affects the printing of corners. A low Jerk setting makes the printer move slowly through the corners - but too low and you could have blobbing and slow printing.

    Tighter corners cause more slowdown.

    A high Jerk setting causes the printer to move quicker through the corners - increasing print speed - but too high and the printer will vibrate more, causing waves in the outer perimeter (ringing) and other issues - possible including missed steps.

    Documents

    Issues

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    Comments

    Cda3bba1a8ea03ceceaa02db4a75f136?default=blank&size=40Nonametruck added this to the Tinker collection ago
    515181f614e0ce61f55782828ce5abcc?default=blank&size=40Bahremu added this to the to print collection ago
    Mini il 570xn.1343682359 2jz9The 3D printing Guy commented ago

    Nice design, good contribution to the community here!

    6e54817fba3b87eef1c609a98045e062?default=blank&size=40Roberto Cabellon added this to the 3D Printing collection ago
    024af13d4fd14a2abbd283d60c19dfc6?default=blank&size=403DFreezeMe added this to the Calibration stuff collection ago
    Mini maker doc roundmager added this to the Trium3D collection ago
    5f1a922a2c90470efa4aada10226e002?default=blank&size=40Northernlights added this to the Calibration collection ago
    Mini pugwashMalc added this to the Calibration collection ago
    Mini heikorabbit added this to the calibration collection ago
    D45c8debd76c52ae46cc65de41ca3220?default=blank&size=40Paul--W published this design ago