Changing feed rate at certain layers.

[cchisholm 0]

I do a lot of repetitive printing and sometimes like to change the feed rate at certain layers or millimeters.  For instance if or printing a partially threaded bolt standing on end, I might want to print the raft and bolt head at 200%, then slow down to 100% for the bolt shaft, and then slow to 25% at the beginning of the threads.  This works perfectly if I stay with the print to modify the speed at those points.  I’m looking for a way to automate that process (preferably in slicing) so that I don’t have to hover over the printer to make sure I crank the speed up or down at the appropriate layer/height.

 

is that possible in cura?

[GregValiant 1,251]

If you have the latest version of Cura there is a post-processing plugin "Change at Z".  You can put more than one instance in your file.  I think I heard some noise that it was glitchy, but it works OK for me.

The other alternative is to do it by hand in Notepad and insert M220 S??? at the layers or Z height where you want to change speeds.  The bottom layer in Cura is Layer 1.  The bottom layer in a Cura generated Gcode file is Layer 0.

Speed and Flow changes made using M220 (or M221 for flow) in the Gcode change the printer calculations and they do not go back to 100% at the end of a print.  If I make speed or flow changes in the gcode I always put a line right at the end M220 S100  or M221 S100 to make sure if I start another print right away it starts at 100%.  Those settings do return to 100% if you power off the printer and turn it back on.