Ghosting or layer shift issue. Hi everyone, I'm having an issue I can't track down. Not sure is it's a rippling/ghosting issue or layer shift. Printing a 20x20x20mm calibration cube. Once it starts printing the X right after it I get this effect. Doesn't look like the typical rippling/ghosting as it makes those layers stick out further. I attached a video I slowed down to show movement. I checked my belts/ tightened, pulleys ok. I'm have a prusa clone with a proximity sensor running skynet firmware. Any suggestions would be great. [youtu.be] Thanks, Mark https://reprap.org/forum/read.php?262,732901,732901#msg-732901 Sun, 09 Aug 2026 11:58:38 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?262,732901,744845#msg-744845 Re: Ghosting or layer shift issue. https://reprap.org/forum/read.php?262,732901,744845#msg-744845 Paul Wanamaker Printing Fri, 03 Feb 2017 01:07:46 -0500 https://reprap.org/forum/read.php?262,732901,744164#msg-744164 Re: Ghosting or layer shift issue. https://reprap.org/forum/read.php?262,732901,744164#msg-744164 Issue looks like it's gone. After adjusting the extrusions width manually it was still there slightly. Once I brought down the overlap percentage (set it to 12% instead of default 15%) did the trick.

Thanks for your help.]]> MarkM_NJ Printing Tue, 31 Jan 2017 22:55:25 -0500 https://reprap.org/forum/read.php?262,732901,737559#msg-737559 Re: Ghosting or layer shift issue. https://reprap.org/forum/read.php?262,732901,737559#msg-737559
Quote
MarkM
I did as Paul suggested and printed the cube 45 degrees. The issue still showed up. I'm seeing a difference when manually adjusting layer thickness instead of letting slic3r calculate it.

Hmm, the two prints were identical? I actually didn't expect them to be exactly the same. Tricky. Perhaps the problem is with variations in extrusion rate.

Quote
MarkM
I'm seeing a difference when manually adjusting layer thickness instead of letting slic3r calculate it.

That's interesting. I think you are actually manually adjusting extrusion width?

If there is an issue with extrusion (due to varying pressure in the extruder) then here is a good test:
On the Advanced tab:
Set all of your extrusion widths to the same value: your nozzle diameter * 1.2 (this is a safe value).
It is best to start with all these values set to a specific value (not auto) so you can control what happens.

On the Speed tab:
Set all the speeds to the same value, say 25 mms.
It is best to always set speeds to a set value instead of auto so you can control what happens.

Then when you print the cube, all the features will print at the same extrusion rate, and that will at least rule out some possible issues, including a known bug in Slic3r.]]> Paul Wanamaker Printing Wed, 11 Jan 2017 01:02:50 -0500 https://reprap.org/forum/read.php?262,732901,737552#msg-737552 Re: Ghosting or layer shift issue. https://reprap.org/forum/read.php?262,732901,737552#msg-737552 I did as Paul suggested and printed the cube 45 degrees. The issue still showed up. I'm seeing a difference when manually adjusting layer thickness instead of letting slic3r calculate it. Still fine tuning to see if I can get rid of it completely.]]> MarkM_NJ Printing Wed, 11 Jan 2017 00:23:45 -0500 https://reprap.org/forum/read.php?262,732901,734534#msg-734534 Re: Ghosting or layer shift issue. https://reprap.org/forum/read.php?262,732901,734534#msg-734534 I looked closely at the photos.

One way to test this is to rotate the part 45 degrees, print and observe. If it was only an extrusion issue, then the two prints would be identical.

I suggest that this is caused by backlash, because it appears there is a slight shift when changing direction. The direction it is shifting will give you a clue about which axis to work on. This appears to be identical to another reprapper's issue - and they solved it finally by repeatedly tightening the belt, but there are several things that could contribute.

I suggest looking at the following:
- Make sure the axis moves very freely with no hangups, or resistance from wires or filament in one direction.
- Make sure there is no play in the axis at all
- Make sure that everything is tight, including the extruder. Grab it and try to wiggle it. Does something get loose when hot?
- Are you using a belt known to have low backlash - like GT2?
- Are all the grub screws tight, and a flat ground on the stepper shaft? Do not miss this.
- Are the belts quite tight? One way would be to pluck them - do they make a medium tone?
- Do the belt mounts flex at all, or anything else flex for that matter?

Additional possibilities on the Shifted Layers wiki page.

Hope that helps.]]> Paul Wanamaker Printing Sat, 31 Dec 2016 17:51:02 -0500 https://reprap.org/forum/read.php?262,732901,733019#msg-733019 Re: Ghosting or layer shift issue. https://reprap.org/forum/read.php?262,732901,733019#msg-733019 elwood127 Printing Sun, 25 Dec 2016 18:52:56 -0500 https://reprap.org/forum/read.php?262,732901,732923#msg-732923 Re: Ghosting or layer shift issue. https://reprap.org/forum/read.php?262,732901,732923#msg-732923 JamesK Printing Sat, 24 Dec 2016 21:35:13 -0500 https://reprap.org/forum/read.php?262,732901,732921#msg-732921 Re: Ghosting or layer shift issue. https://reprap.org/forum/read.php?262,732901,732921#msg-732921
I'm printing at 30/mms. This is driving me crazy. Maybe I'll try dropping it down to 15/mms to see if I can spot it.]]> MarkM_NJ Printing Sat, 24 Dec 2016 21:17:01 -0500 https://reprap.org/forum/read.php?262,732901,732920#msg-732920 Re: Ghosting or layer shift issue. https://reprap.org/forum/read.php?262,732901,732920#msg-732920 JamesK Printing Sat, 24 Dec 2016 21:04:19 -0500 https://reprap.org/forum/read.php?262,732901,732904#msg-732904 Re: Ghosting or layer shift issue. https://reprap.org/forum/read.php?262,732901,732904#msg-732904 MarkM_NJ Printing Sat, 24 Dec 2016 15:11:12 -0500 https://reprap.org/forum/read.php?262,732901,732901#msg-732901 Ghosting or layer shift issue. https://reprap.org/forum/read.php?262,732901,732901#msg-732901 I'm having an issue I can't track down. Not sure is it's a rippling/ghosting issue or layer shift. Printing a 20x20x20mm calibration cube. Once it starts printing the X right after it I get this effect. Doesn't look like the typical rippling/ghosting as it makes those layers stick out further. I attached a video I slowed down to show movement. I checked my belts/ tightened, pulleys ok. I'm have a prusa clone with a proximity sensor running skynet firmware. Any suggestions would be great.

[youtu.be]

Thanks,
Mark]]> MarkM_NJ Printing Sat, 24 Dec 2016 14:56:09 -0500