Blobs on extrusion direction changes only with one brand of PLA
New to 3D printing. I've had many happy hours printing with the PLA that came with my MK3S and two other filament types without having to do anything but tune the first layer calibration but having trouble printing with a new gold PLA filament that I expected to have the same basic properties. After several attempts at calibrating the first layer (that looks pretty good), I consistently get failed prints due to the IR sensor running into these goobers (blobs) that occur at the direction changes of my infills. Is this a retraction distance issue? The recommended temps on this filament are nearly identical to the 215C nozzle 60C bed recommended temps that work fine with my other filaments but this filament clearly has different properties. Is this just a quality issue with the filament, or can this be corrected with some parameter changes? Photo attached.
Also want to mention that I'm generally really happy with the MK3S which has been one of the few hobby purchase experiences that has thoroughly exceeded my expectations. Assembling and and learning to use it even with some minor challenges here and there has been really enjoyable and instructive. Instructions, quality of parts, electromechanical engineering and software have so far proven to be an excellent value in this domain. Hope Prusa can maintain the open and light spirited design and business philosophy going forward.
Sorry about the rotated photo. Not sure how to correct that. Not the blobs at the direction changes of the support pattern and the stringing. Doesn't look like the photo the examples of stringing I've seen in various troubleshooting guides. This filament has the same recommended temps as my other filaments that print fine at these temps. Not sure what's actually going on. I aborted this print, but eventually the IR sensor collides with one of the blobs.
RE: Blobs on extrusion direction changes only with one brand of PLA
BTW the Prusa badge print from the SD card looks pretty good. This suggests there must be a parameter I can tweak in the sliced but not sure where to start.
RE: Blobs on extrusion direction changes only with one brand of PLA
Other filaments seem to print fine with pretty much identical slicing and temp settings.
RE: Blobs on extrusion direction changes only with one brand of PLA
Try with a different filament. The silky filaments can be tricky. If you have no problems with another filament, you are going to have to experiment to find what, if any, settings will work for the silk. The adhesion on your 1st pic is poor. If you have the same problem with other PLA, try giving your smooth sheet a good wash under the kitchen sink with Dawn dish soap or your local equivalent. Wash it with a plain paper towel and dry it with another. Above all else, avoid touching the print area. Also be sure you've properly calibrated your Live-Z setting. Jeff Jordan's "Life Adjust" procedure is recommended.
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RE: Blobs on extrusion direction changes only with one brand of PLA
@bobstro
Thanks. It is only this silky filament that's giving me trouble. I'm hoping I can dial in the parameters so I can use it. I took a few more photos under a microscope. Not sure that helps, but interesting 😀 It seems to go from translucent to cloudy white in places. One photo is from the support infill zoomed in from my original photo. The other two are a comparison of the unloaded ends of the filament for the working silver filament vs the problematic silky gold. Hoping the photos might provide a close as to what setting changes I can try. Also wondering if the cloudy spots are bubbles due to moisture or something else.
In the next photo you can see that same cloudy color in the unloaded filament end. The light spots along the whisker-like end are not reflections, it's cloudiness in the actual material that also shows up in the support material photo. So these silky filaments are frequently problematic? I can poke around on the web searching for that specific issue.
RE: Blobs on extrusion direction changes only with one brand of PLA
Eventually got it to print by lowering 'move' rates and raised the nozzle temp from 215 to 220. I had full auto supports turned on so the print is not very clean due to all the support that had to be removed. I started by setting 'ColorFabb bronzeFill' for the PLA type, guessing that it might be similar. I then lowered all of the 'Speed to move' settings by about 10 mm/s, and set the infill down to 10%. Out of all those variables I changed, something at least prevented the print from failing. Could probably get a cleaner print by playing with restricting the supports.
Attached the Prusa Slicer project .mf file in case that helps someone else using this filament. This was one of the Mika3D filament 3-packs available on Amazon. I found a few reviews of this exact same material, mostly positive. There were a couple of references to having issues with it but it seemed to vary quite a bit from having a really tough time to printing right out of the box.
Needless to say the print is a little ratty 😎