Inconsistent layer shifting

[Semus 0]

Hey guys, take a look at this photo. As you can see, the layers on the left (red square) and the layers on the right (red circle) aren't consistent. The layers on the right seem to have shifted in the Y-axis, but only in a certain spot on the print. The layers on the left are unaffected.

I'm not exactly sure how to fix this. What's even worse is that I printed a wing from the ultimaker airplane model, and it had zero shifting like this. I've also noticed this happening on a much smaller level, and only near holes.

Even weirder is that on the backside of the model (where the shifts are happening), the model is fine, as if the shift never happened.

Print speed is set to 30mm/s and travel speed is set to 175mm/s. I could post my other settings if needed.

Any ideas?

Edited April 3, 2017 by Guest

[Semus 0]

So, I think this might be caused by retractions. Whenever there are holes in my models, the printer will retract at certain locations, and whenever the printer retracts the filament, depending on how much is retracted, and how long it has been between the retract and the next print spot, different amounts of filament may be extruded in certain spots afterwards.

I'm not certain this is the cause, but I'm leaning towards this, as prints without retractions (ie, a box or plain circle) are printing without issues. It's only when retractions are introduced  that I'm seeing these inconsistencies.

Edited April 3, 2017 by Guest

[geert_2 560]

I have no idea about the shifting, as I have never seen that. I guess you already took a look at the "layer view" in Cura, or in any other slicer, so it is not a defect in the gcode file?

Apart from that, you also seem to have "warping" in the corners of the models, so your bonding to the build plate isn't optimal. This could cause the models to come loose during printing.

Depending on your preferences, I would suggest you try any of the bonding methods commonly discussed in this forum: dilluted wood glue (1 part glue in 10 parts water, as promoted by user gr5), hair spray (spray it on a tissue, then wipe the glass plate, as promoted by neotko), 3D LAC spray bottle, or for PLA-filament my "salt method": wipe the glass plate with a tissue moistened with salt water, and gently keep wiping while it dries into a thin almost invisible mist of salt stuck to the plate. Or if you use the standard glue stick, smooth it out with water after applying.

[Semus 0]

I have no idea about the shifting, as I have never seen that. I guess you already took a look at the "layer view" in Cura, or in any other slicer, so it is not a defect in the gcode file?

Apart from that, you also seem to have "warping" in the corners of the models, so your bonding to the build plate isn't optimal. This could cause the models to come loose during printing.

Depending on your preferences, I would suggest you try any of the bonding methods commonly discussed in this forum: dilluted wood glue (1 part glue in 10 parts water, as promoted by user gr5), hair spray (spray it on a tissue, then wipe the glass plate, as promoted by neotko), 3D LAC spray bottle, or for PLA-filament my "salt method": wipe the glass plate with a tissue moistened with salt water, and gently keep wiping while it dries into a thin almost invisible mist of salt stuck to the plate. Or if you use the standard glue stick, smooth it out with water after applying.

 

It's quite possible it is a defect in the code. I haven't investigated this, and I'm not even sure how to do that. I have taken a look at the layers view in Cura, and did not see anything abnormal, but I don't know what I should be looking for.

As far as the warping, I do seem to have a problem there. I noticed this, but it was too late to abort the print. I do use the glue stick method, but it isn't as consitent as I'd like. I will try your salt water method, and see if that works better. Would be much easier to clean, as well.

[geert_2 560]

If it is in the gcode, I guess you should be able to see it in Cura when - in layer view - zooming in quite a lot. The "jumps" should be visible.

Concerning the "salt method" for bonding, see the full manual (PDF-file) with pics at:https://www.uantwerpen.be/nl/personeel/geert-keteleer/manuals/

[Semus 0]

If it is in the gcode, I guess you should be able to see it in Cura when - in layer view - zooming in quite a lot. The "jumps" should be visible.

Concerning the "salt method" for bonding, see the full manual (PDF-file) with pics at:https://www.uantwerpen.be/nl/personeel/geert-keteleer/manuals/

 

Thanks for the info!

I'm almost convinced the shifting has to do with retractions. Almost...

I've gone ahead and re-tuned the machine for straightness, tightened the belts, and lubricated everything. We'll see if that has any effect on things.

Edited April 4, 2017 by Guest

[shayan 0]

did you figure out the solution for this....if so please let me know. i am also facing the same issues and not bale to rectify at all. its taking my nerves down. all belts pulleys and screws are tight.  please some help would be appreciated.