Firmware Retract zhop/lift speed


By adavidm 20 April 2017 21:31

Member · 21 comments


Is there a default feedrate for the zhop/lift during a firmware retract? I'm wondering if that feedrate has a bearing on the size of the blob left behind following a retract and if it can be tuned at all? Smoothieware has a Q parameter to the M207 command that seems to allow this to be configured. I had a quick look in GCodes2.cpp, but M207 makes no mention of the Q parameter so I'm assuming it's not supported in RRF.

The RetractFilament() function in GCodes.cpp has the following section:

				// Set the feed rate. If there is any Z hop then we need to pass the Z speed, else we pass the extrusion speed.
				const float speedToUse = (retract) ? retractSpeed : unRetractSpeed;
				moveBuffer.feedRate = (retractHop == 0.0 || retractLength == 0.0)
										? speedToUse
										: speedToUse * retractHop/retractLength;
				moveBuffer.coords[Z_AXIS] += (retract) ? retractHop : -retractHop;

but I can't see where the Z speed is being passed as per the comment.

It would be nice to have in the firmware as it would be another setting to play with during a print for fine tuning.




By kraegar 20 April 2017 21:46

Member · 169 comments

By adavidm 20 April 2017 21:55

Member · 21 comments
kraegar wrote

See DC42's answer here:

Completely missed that, thanks!