S3 PRE-PRINT INITIAL PURGE

[AL-X 0]

After bed leveling while the nozzle is still near the front of the bed, and despite "Enable Prime Blob" being turned off in Cura, there is a short extruder purge sequence that will:

-most of the time drag some oozing material into the print area and

-sometimes the extruded material that the printer tries to smear off near the front of the bed will remain stuck to the nozzle and get dragged into the print area.

Is there any reason for that purge when a skirt or brim is used?

How to completely disable it? I see gcode command G280 is related to priming but based on Cura settings my print files have G280 S1 which I understand should not do anything. Guessing it's a firmware issue?

[Smithy 1,145]

Are you sure it is a purging and not only an oozing material during the heat up of the nozzle?

Depending on the material (PETG i.e.) I see from time to time some material oozing on my S3, but never so much that I had problems.

 

Do you have a picture?

[AL-X 0]

This is a relatively clean example I just did where the purge happens to be outside the print area:

 

Edited December 10, 2021 by AL-X

[AL-X 0]

(UM Silver Metallic PLA)

[gr5 2,210]

During bed leveling it cuts all power to heaters (bed and cores).  When leveling is over it has to heat everything back up to temperature.  While it is heating up, the plastic expands and some filament leaks out.  But it should then start printing the skirt (or brim) and get connected to that instead of to your print.

 

Could that be it?

 

Also when it is finally ready to print it does an "unretract" because it retracts at the end of the previous print.