Shifted Print
I am fairly new to 3D printing. Core One is my first. I was trying to print a model and it appears that the entire model shifted about 6.5mm back and 7mm to the right on the first print with PETG. Second print using PLA it shifted back about 10mm to the right about 10mm. Both sides of the part shift. (Pictures only show once side) Other parts that I have printed past this height print ok. I am going to try to export the STL model and then re-slice it. The model looks correct in Prusa Slicer and on the screen of the printer. Anyone have any thoughts?
It looks like you have only a small area in contact with the print-sheet and it's a shape that is likely to warp ... Make sure your print sheet is clean and add a brim to the part. I suspect the part is loosing adhesion then warping up into the head-path causing a crash and consequent layer shift.
Cheerio,
RE: Shifted Print
Also make sure Avoid Crossing Perimeters is turned off. I've seen several layer shifts with it turned on that went away after turning it off.
Formerly known on this forum as @fuchsr -- https://foxrun3d.com/
RE: Shifted Print
Thank you. I am trying another test print with larger brim and also a little different geometry. I do not see the option for the "Avoid Crossing Perimeters", which section is this located in. I will let you know the results
RE: Shifted Print
Print Settings>Layers and Perimeters>Quality
You have to be in Expert Mode to see it.
Formerly known on this forum as @fuchsr -- https://foxrun3d.com/
RE: Shifted Print
Great thank you. With the changed geometry and the brim it did print correctly. I did have some wisps on the supports but I think it may be that the PLA needs to be dried some. I have a dryer that should be here later this week. I am printing another tonight so hopefully this one will print correctly also. Thank you.
RE: Shifted Print
I do have an interesting update on this. I used a slightly different model and I had the shift again. I did use the Brim and also made sure that that Avoid Crossing Perimeters is turned off and I still had the issue. This was using Snug supports.
So I decided to do a print with one part with changing the supports to organic and it printed correctly. All the other settings were the same. It looks like snug supports has an issue with the geometry.
RE: Shifted Print
This is the second thread I see in a week or so with a layer shift when printing multiple copies but printing ok when printing a single copy. I have no clue why that happens but if this starts happening repeatedly to different people it is potentially the beginning of a pattern.
Also check basics like belt tensioning, the few cases I have had my belts have always been lose. You can also maybe try lowering acceleration on travel which is where the printer really speeds up but that really shouldn’t be needed it may be worth trying if the problem persists.
/Anders
No. It's a very old pattern.
When you have a part liable to warp, lose adhesion or otherwise suffer a head crash there is always a chance it will do so and so suffer a layer shift.
When you slice a second copy on the build sheet you double the chance of failure - ten copies, ten times and so on.
The same applies to multipart beds, there are ways to mitigate the problem but the more parts the more risk.
Cheerio,
RE: Shifted Print
No. It's a very old pattern.
When you have a part liable to warp, lose adhesion or otherwise suffer a head crash there is always a chance it will do so and so suffer a layer shift.
When you slice a second copy on the build sheet you double the chance of failure - ten copies, ten times and so on.
The same applies to multipart beds, there are ways to mitigate the problem but the more parts the more risk.
Cheerio,
Thanks for the explanation, that makes sense. I am just too new to this to have seen the pattern.
/Anders
RE: Shifted Print
Thank you. Let me try to print 1 part with snug supports. Then I will also try a print with 2 parts but using organic. I am very new also, I just seems very weird that 2 very similar models both had the issue. When I changed the geometry on one it has printed fine. Thank you for the good suggestions..
RE: Shifted Print
So I did print 1 part with Snug and 2 parts with Organic supports. The 1 part with Snug did fully print but there was an issue on the print but just not enough to make it complete failure and shift but it was around the same layer position as the others. The 2 parts with Organic supports printed great. Please see the pictures below. My recommendation if you have a print shift, try different supports if you are using them.
RE: Shifted Print
Your print looks good with those new supports, but with that amount of shift I'd also check the toothed gears on the motor shafts. The grub screws sometimes work their way loose and the gear slips under moderate resistance.
RE: Shifted Print
This is the second thread I see in a week or so with a layer shift when printing multiple copies but printing ok when printing a single copy. I have no clue why that happens but if this starts happening repeatedly to different people it is potentially the beginning of a pattern.
I saw another post where their motor jumped 100 steps and it was solved by unticking "ensure vertical wall thickness" and "avoid crossing perimeters". Both of those suggest a systemic firmware/software bug like you're saying.