Filament Change Leaves Blob

[jjstohr13 0]

I am able to use the filament change on Cura 4.8.0, but the extruder leaves a blob of material in the printed object where it stops before going to the home position. Is there a way to tell it to stop outside of the print surface. Or is the 30mm initial retract not working or is it not enough?

[GregValiant 1,309]

I think the retraction occurs while the nozzle is still in contact with the part.  Moving 30mm takes a bit of time so you get a deformed area.  You could try setting the Initial Retraction distance to 2 or 3 or even 0.  It would end much quicker and the print head would go to the location without spending so much time in contact with the print.

You can also try using Pause at Height instead.  It's slightly different but I like it for filament changes because I can set the stepper disarm timeout to 1800 seconds (30 minutes) which I find to be much better than the 2 minutes that it usually is.  I don't use the initial retraction at all.  On the restart I just pull about 3mm of filament back after pushing enough by hand to change colors.  That keeps it from leaving a blob on the restart.

[jjstohr13 0]

Thank you for the advice. I wasn't sure why it was waiting, so I will lower that and see what happens. I tried the pause at height but didn't know how to set it correctly. Any advice on that?

[jjstohr13 0]

That  worked perfectly. awesome to get this kind of advice!

[GregValiant 1,309]

I've made several posts here about using Pause at Height.  The main thing is that you have to set it to "Layer" and not height.  If there are Z-hops in the file then Pause at Height "by Height" can be fooled because the Z keeps jumping up and down.  A layer is a layer except that in a gcode file layers start at 0 and in Cura they start at 1.  So if you look at the Cura preview and see you want to stop at layer 10, in the plugin you would put layer 9.

[jjstohr13 0]

Awesome, thank you.