Vertical seam occurring in the same place?
I'm using a MK3S+ and trying to print some roughly cylindrical objects. I used the current version of PrusaSlicer with default settings, and the models were centered on the bed.
They printed pretty well, but both of them have a vertical "seam" in the same place: approximately 5 degrees above the X-axis, or about 2:30 on a clock face. I haven't tried printing additional "debugging" objects yet; I thought I'd check if anyone recognizes this symptom first.
Some other data points:
- The models were made in OpenSCAD with a pretty high number of edges approximating the curved side (100 or higher).
- One object has a completely vertical, smooth curved wall, and the other has a curved wall that is vertical with some additional texture.
- I used different filament for the two objects that exhibit this seam.
- I hadn't used the printer for a couple of months before printing them.
Any ideas on what to try next would be appreciated.
RE: Vertical seam occurring in the same place?
Update: I can see the seam in PrusaSlicer after slicing if I rotate the object around. (Lesson learned: look at it from all angles after slicing!) So that narrows it down to the modeling-to-slicing portion of the process, and should let me debug it without having to print anything 🙂
RE: Vertical seam occurring in the same place?
I'm not sure what the problem is? Yes, a cylindrical object will have a vertical seam. You may try to set seams to random in Prusaslicer's print settings but I for one usually prefer the aligned look of seams over random zits. You may also want to use the paint-on seams function to place the seam where it is the least conspicuous.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: Vertical seam occurring in the same place?
Thanks, I'm still new enough at this that I didn't realize it was basically unavoidable.
RE:
We were all noobs at one point! 🙂
As far as the z-seam is concerned: the way FDM printers build up a model is by laying down layer by layer. That means, at the end of a layer the nozzle has to be moved up (by the amound determined by layer height) to start the next layer. That's where the Z-seam is formed. For most models, Prusaslicer is clever enough to hide the seam in corner, but alas cylindrical objects have no corners, so the Z-seam will alway be visible. Prusaslicer has several options to adjust seam placement, as I indicated in my previous post, and depending on your object and intended use, one or the other may be preferrable. In recent versions, Prusaslicer added "paint-on" seams, which are a great way to have even more control over the seam placement.
Extra-tip: for most parameters in Prusaslicer's settings screens you can click on the title to go directly to the knowledgebase article describing that function. Here, if you click "Seam position" it takes you to https://help.prusa3d.com/article/layers-and-perimeters_1748#seam-position
A slightly advanced tip: Some objects can be printed in "vase" mode. In vase mode, the hotend moves in a contiguous line from beginning to end and doesn't make jumps at the end of a layer. However, there are serious constraints on the topology of the object for vase mode to work. Here's a pretty good overview: https://the3dprinterbee.com/prusaslicer-spiral-vase-mode/
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...