first layer nozzle drag?
Howdy folks,
Kit built MK2S here, I've got it dialed in pretty well (I think) and am getting mostly great prints. But recently I noticed that on the first layer only the nozzle is dragging through the freshly laid down lines when it repositions. On most layers you can visibly see it z-hopping over previously printed layers, but not on the first one.
I'm slicing with Slic3r Prusa Edition, using the bundled profiles that come with the driver bundle. The choices under filament type and print settings don't seem to matter. I'm using a copy of the "Original Prusa i3 Mk2 with ZHop" printer profile that I have added one comment line to the "Before layer change G-Code" section. it just adds a comment about what layer is about to start.
The model being printed doesn't seem to matter either... but obviously some designs don't have bottom layers that cross over each other as much or as obviously as some of the ones I've been printing lately. In most of my prints this is totally invisible. But I'm starting to work with some transparent and translucent materials where the details of the first layer are quite evident in the final object... so I'd love to stop this.
In this image you can see the mark it made. The layer infill had completed the first half in the upper left corner of the part, then the head moved in a straight line to the lower middle to finish the 2nd half of the layer in the opposite direction.
In this one (with the horrible focus because I didn't pause the print and it moved just as I was shooting, but this was the best of several shots I got before the second layer was added) you can see it finished in the lower right corner, then moved diagonally up to start the next piece (same as this piece) in the middle of the bottom edge of the piece.
Is there some setting I'm not aware of that I should be fiddling? is there a bug in the default profiles? is there a bug in Slic3r with first layer handling? Anyone have any advice on this?
Re: first layer nozzle drag?
I also have that issue. No use even after calibrating and fine tuning z motor.
Re: first layer nozzle drag?
My Prusa MK2 kit built does the same. Only on the first layer.
Re: first layer nozzle drag?
Go to Slic3r Printer Settings Tab.
Have a look to the point: Only lift Z.
If this value starts -Above Z:- with 1 set it to 0.
Then have a look for the -Lift Z:- value too.
If this one is 0 set it i.e. to 0.5
Hope this helps
Re: first layer nozzle drag?
Go to Slic3r Printer Settings Tab.
Have a look to the point: Only lift Z.
If this value starts -Above Z:- with 1 set it to 0.
Yup, it's set to 1... so I guess the question now is, why did Prusa set it to 1 instead of the default 0?
The below value of 199 I can understand... given a 200mm print height, you wouldn't want it trying to lift on the 200mm layer and hitting the endstops, then dropping back down and ruining a print on the very last millimeter... better to risk dragging.
Re: first layer nozzle drag?
I solved mine by enabling Z hop on Cura.
I configured Slicr as what 3DBlaster suggested and it worked. Thank you 3DBlaster.
Re: first layer nozzle drag?
Go to Slic3r Printer Settings Tab.
Have a look to the point: Only lift Z.
If this value starts -Above Z:- with 1 set it to 0.
Yup, it's set to 1... so I guess the question now is, why did Prusa set it to 1 instead of the default 0?
The below value of 199 I can understand... given a 200mm print height, you wouldn't want it trying to lift on the 200mm layer and hitting the endstops, then dropping back down and ruining a print on the very last millimeter... better to risk dragging.
I agree, is there are reason for the setting of 1 instead of 0?
I've changed the setting and will eventually find out.
Re: first layer nozzle drag?
What do you guys think the issue is here? I would think that the live z would need to be adjust up however that doesn't always seem to fix the issue. I can get it set and then the next print the layer issues shows up again. I have tried hot calibration and moving the Z axis up while pre-heating but it doesn't always help. This is a brand new printer that was pre-assembled so I am a bit frustrated. seems like the bed honestly is not level and the mesh calibration is not correcting for this.
Blue E-Sun PLA +
210 Extruder and 55 Bed
Sliced in S3D (also tied slicer and Prusa Control but the issue popes back up)