I recently had to install a new micro lidar when the first one was melted by a large goober of PETG. Every print since the new sensor has these lines on anything cylinder shaped. When I was installing the micro lidar and working with bamboo support, I showed them a picture of this issue and they replied that the line is considered normal. Because this never happened with the 1st micro lidar, I’m a bit suspect. I’ve printed with several different filaments of PLA and PETG. And I’ve also had several different files printed since the install. As you can see from the picture, it happens on supports and on the actual main print item too. Any help in whatever settings I can adjust to stop this from happening would be appreciated.
It looks to me to be the z-seam - the point at which the head stops briefly as it moves up to the next layer.
It looks far too pronounced, though. I know there is a setting to you can move the z-seam, so it appears in a different location on each layer, or at a sharp edge. I don’t think that will fix the pronounced problem. though, just shift it around.
Have a look in Bambu Studio if there are any other setting around the z-seam. Perhaps the head is spending too short a time , or underextruding during a layer change?
I’m sure someone far more knowledgeable than me (@Olias 
) will be along soon and be able to give you a definitive answer.
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try scarf joint
letters letters
Whats the differences between the red one and the others ?
and could it be anything to do with the scarf seam ( around entire wall ) ?
OK, so to be clear, you showed those photos to Bambu Support and they told you it’s normal??? Yet another fine example of quality tech support from the boys in China… NOT!!! That answer is Bullsh*t. That is NOT normal.
The joint seem you’re experiencing does have a setting in the slicer that will allow you to minimize the gap. I no longer use it as much because since the introduction of Scarf Joints, that feature is really obsolete but here is how it works.
This is what it looks like.
Now having said that. I’ve run no experiments on organic tree supports and have no idea whether or not this seam setting will affect the supports as was noted in your example. However, the pictures I just shared illustrate that you can manage the seam yourself on the object.
My settings look just like your picture
Yeah, the “this is normal” comment was highly irritating.
It seems the smart scarf seam application has replaced the seam gap setting as I’m not seeing seam gap is available to me in Bambu Lab version 1.10.2.76. I’m going to try setting the seam position to random.
My apologies. I always forget to mention. I only use Orca as Bambu Studio really has become a degraded application over time and Orca looks just like Bambu Studio since it is compiled from the same code. But you need to turn on either developers mode or advanced mode to get to these features. Who knows, they may already be in Bambu Studio if you turn on the advance features but Orca is just so much easier.
This is only related to the scarf conversation.
The real Scarf settings moved to the filament settings panel (scroll down first tab when opened).
This was because not all materials are capable or suitable for the scarf technique.
I enable full scarf options for all of my fidget spinners to make them spin better.
I opened developer mode setting the seam location to random and the seam gap to 2%. All other settings are default. I printed the jar again Parametric Jar (Change size to your needs) by dfreshkremer - MakerWorld which is shown in my first image. This was the result. Little random dots all over the surface
This is normal behaviour for setting your seam to random.
I’ll try again with setting the seam to aligned and upload a new image of the results. I’m just frustrated because before we installed the new micro lidar we never had these lines on our prints - cylinders would come out seamless.
Have you done a factory reset and a full calibration?
OK, I think I see what may be happening here. You’re still experiencing a seam gap in your filament calibration, meaning the gap is still present. Using the random seam location, which normally helps “hide” the problem, isn’t working in a gap this extreme.
What you’ll want to do is to go back one step in the troubleshooting process and adjust the seam gap as I posted above. Unfortunately, this can only be done through repetitive trial and error. One tip I can share to save time is to create a cylinder primitive with dimensions of 20x20x10mm, which will print quickly. Then, clone it three or more times to make copies on the build plate. Modify the seam gap for each primitive using the model submenu from 0% to 20% in 5% increments. This will allow you to print multiple tests quickly while only going through the purge cycle once.
CTRL-K to clone
Set the objects Seams separately.
Then print and note which one is closest to no gap.
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Just my 2 cents - I have default setting of aligned/back and 8% seam gap from my testing and found this is pretty much the optimal for my prints that I re-saved all the profiles with it to never change it again.
edit: it obviously depends on model, slice what you are doing sure! But at times it is also helpful to know what “just works”
The above advice Olias gave is a great start to figuring this out…
I did the above with both primitive cylinders and torus. Unfortunately my partner moved the torus before I could label them.
The line appears when the extruder stops directly facing the enclosure door. I noticed a small bump sound when a new layer is started on the outside wall. That might be normal operations, but it didn’t make that sound when making the inner circle of the torus at the same location. There’s also a line on the inner ring of the torus but in a different location than the outside seam.
The cylinders themselves tell a story here. You’re not getting any advantage for closing the seam gap to zero. That tells me there is a flow ratio issue going on here. You will want to calibrate the flow ratio.
What is also occurring here is this rippling I’m seeing. That could be caused by the type of infill you’re using and also too thing outer wall and last but not least, wall sequence.
Try to print a single torus at 0 seem gap. But ensure that you have at least 3 outer walls and that your wall sequence is outer/inner as opposed to inner/outer which is the default.
Then change your infill to something like gyroid or 3D Hexagon. The reason for this is that these two infills provide a crisscross in the vertical as well as horizontal plane. If there is an issue with filament shrinkage, you’ll be able to see a crisscross pattern.
The problem with Grid infills and other vertical infills is that it’s impossible to determine if it is the infill causing this ribbing or the filament being out of calibration or if the outer walls are too thing.
Now if the torus evens out after these changes, and the gap is still present, then you’ll want to take a look to see if pressure advance is enabled and calibrate that. Also consider calibrating flow ratio too.
Now I’m ready to start using the orca slicer. I found a YouTube video of someone showing how to get rid of Z seam and the only final solution was using the Orca slicer.
The torus didn’t seem to like the 3D honeycomb infill. I did two prints to be sure and noticed the lines of filament left outside the shape with both prints. The first picture is before removing from the plate. The second is the bottom.
I’m running auto calibration of flow dynamics right now.
For overhangs, Inner-Outer wall printing order usually works best.
With Outer-Inner, the filament can only sit on a corner of the previous layer. With Inner-Outer, it sits on that corner AND sticks to the filament next to it on the same layer.