Cura 5.1 stubborn unable to slice error

[Modlet 0]

I'm wondering why it's difficult to correct information for the retraction settings that prevent slicing with "unable to slice" error. I don't know how the incorrect values have been saved with presets, but clearly inappropriate values appear for these settings sometimes, which result in the following error:

 

Unable to slice with the current settings. The following settings have errors: Retraction Prime Speed, Retraction Speed, Retraction Retract Speed

 

The vexing issue is that the same error occasionally continues to appear after setting these values to something more reasonable by entering (for example):

 

Retraction speed: 3.0

Retraction Prime Speed: 3.0

Retraction Retract Speed: 3.0

 

I've been correcting the issue by replacing the configuration folder with a backup of one that allows slicing to work. The values for those settings appear as those I've listed above.

 

Can you help me find a more reasonable way to remedy this problem than restoring the configuration folder from backup? Thanks.

[GregValiant 1,488]

What printer is that?

The ""machine_max_feedrate_e" is often called out in the printer definition file.  If you attempt to put in a retraction speed higher than the defined max E speed then (as you have found out) Cura won't slice.

In the MarketPlace is a plugin called "Printer Settings".  Install it and many of those "other" settings will become available to you.  You can increase the "Max E" within the Printer Settings and Cura will allow higher numbers in the retraction speed settings.

But that doesn't mean the printer will react to them.

Within the printer the Max Feedrates are stored in M203 and the Max Acceleration settings are stored in M201.  Cura doesn't know what those Maxes are and so depends on the values in the printer definition file to tell it when a user has entered an invalid value.  You could configure Cura to allow for a Max E Speed of 200 but when the printer sees that it will limit the speed to whatever the value is in M203.

For a reference I have a regular bowden setup on my Ender 3 Pro.  I run the retract and prime speeds at 35mm/sec for PLA.  I sent an M203 E50 to my printer so it would actually hit my 35mm/sec setting in the gcodes.

There was a poster here who had their retract distance set to 7mm and a retract/prime speed of 1mm/sec.  Every retraction was a 14 second hit to his print time.

 

Let us know what printer that is because occasionally there will be an error in the definition file (which are submitted by members of the Cura Community, or by the printer manufacturers).

 

Edited August 30, 2022 by GregValiant