First ASA Print - Odd Surface Texture
So I did my first ever ASA print, and it didn't print exactly as expected, so I have some questions.
First off, sorry, I do not have the .3MF file. I'm away from my house today. However, the file was this Stevenson screen from Thingiverse. The main screen portion, printed at 100% scale, upside down (louvers angled up). PrusaSlicer 2.6.0, Prusament ASA selected, 0.3 mm DRAFT, no supports, 15% grid infill. I did enable extra perimeters for overhangs but no other non-default options. Printed with Prusament Signal White ASA. MK4 inside a Prusa Original Enclosure. ~25 minute pre-heat, enclosure temp from Prusa thermometer stabilized at ~35 °C after an hour or two.
Two things happened. Firstly, I started getting what I thought was over-extrusion as pictured below. At this point I used the Tune menu to drop the flow, I did 95%, then 90%, then later back up to 92%. Not all the tuning was done on this layer, but the initial drop seemed to fix the layer bulging on the front right, but I later noticed the print appeared to have pulled off the bed on this front side, which probably explains the "over-extrusion".
However, the other thing was the outside surface of the print wasn't smooth. There are flat surfaces from the STL creation process not having enough triangles, but it should have been smooth otherwise. Instead, the outside surface is...textured? What would cause this? Again, I did tweak the flow a bit, but the first louver was mostly printed at 100%, then dropped down to 90% before returning to 92% by the middle of the second louver or so, and left there the remainder of the print. The flow adjustment did not seem to change the "texture" on the outside. What could cause this?
RE: First ASA Print - Odd Surface Texture
I think I see what you are describing in the second photo... Best guess would be insufficient cooling between layers; i.e., the previous layer is being distorted slightly by the successive layer. Try increasing the cooling or decreasing the speed and see if that makes a difference. Other possibilities are over-extrusion or damp filament, but I suspect you already considered those.
RE: First ASA Print - Odd Surface Texture
my layer looks like that on 1st picture when print warps or there is Z offset problem.
mini+ [bondtech dual drive, revo, reprinted with PA11-CF and ASA] lives in photo tent.
mk4 stock (with some parts reprinted) lives in prusa enclosure.
RE: First ASA Print - Odd Surface Texture
The horizontal layering bulging up was definitely warping on that side.
The outside texture, two things. First, when I flipped the print over yesterday, when viewed from the top, it's hard to see the texture vs as it is in this photo.
Secondly, one thing I didn't mention is slicing was kinda odd. On these louvers, they were printed with 4 perimeters (two inside, two outside). I'd expect it to slice by printing 4 concentric circles. And on some layers, it did. On others, it would print half a circle on one of the inner perimeters, then reverse and print half a circle right next to that on the second inner perimeter, then print the outer perimeter, but in a complete circle, then do the innermost perimeter, then finish with the two remaining half circle inner perimeters. And not all of these half circles were lined up layer to layer. So I wonder if the texture is just due to a bunch of the layers print half the layer with the inner perimeters done, and half the layer with no inner perimeter, so the filament is squeezing out slightly more when the inner perimeter is already printed, and not as much when the inner perimeter is not already printed.
I'll look at the slicer toolpath in more detail later today.
RE: First ASA Print - Odd Surface Texture
Just an idea in case you did not encounter this problem before: is your model one big merged part or does it consist of several single parts? There is a difference between slicing single parts that are close together and slicing one big merged part.
RE: First ASA Print - Odd Surface Texture
It was all a single part. I forgot to add the link to my first post: https://www.thingiverse.com/thing:4153206
RE: First ASA Print - Odd Surface Texture
The half circles (not) aligning could have to do with your setting for seam placement? I loaded the 3mf file into my PrusaSlicer and I see four concentric circles on the louvers (4 perimeters). Could you show a screenshot from your slicer?
RE: First ASA Print - Odd Surface Texture
Finally back at my main computer. Here is what the slicer did on that print. A lot (but not all) the layers it did a semi-circle of inner perimeter, then looped back and did the second inner perimeter, then did the outer external perimeter as a full circle, then then inner external perimeter as a full circle, then finished by putting a single, very fat piece of inner perimeter on the section that didn't get inner perimeter the first time (instead of two perimeters):
I've attached the 3MF file to this post. Also, what's odd is on my laptop I downloaded this part, sliced the STL with the same settings, and did NOT get this weird slicer behavior. Each layer had four concentrically printed perimeters. Not sure why...
RE: First ASA Print - Odd Surface Texture
I'm printing this a second time, but I've flashed my MK4 with 5.0.0 RC firmware, and using the 0.2 mm SPEED profile. I also dropped the infill since it was just a couple lines in the circular supports and wouldn't add much. 10:39 instead of 17:00 (11 hours if I hadn't dropped the infill). We'll compare results once it's done, since this one sliced with 4 concentric circles on all layers.
I wonder what the speed would be once they release a 0.3 mm IS profile, or fix the slow speeds on the 0.6 mm nozzle IS profiles...