Yes, 3D print.
Anycubic Kobra 2 Max.
Clas Ohlson PLA Pro filament (there's better for sure).
This printer is new for me but I haven't seen such "clutter" in the middle of the print before. Yes, I have printed with an other machine..
The back side of the print is ok.
Anycubic Kobra 2 Max.
Clas Ohlson PLA Pro filament (there's better for sure).
This printer is new for me but I haven't seen such "clutter" in the middle of the print before. Yes, I have printed with an other machine..
The back side of the print is ok.
I see a few issues in this print.
The filament is probably wet. These bubbles, like little pimples, are usually caused by a wet filament. The moisture boils and create these imperfections. Sometimes overextrusion also causes these type of imperfections, but they tend to be more pronounced than the ones in your print.
The temperature might be a little off as well. Probably too high. Check the filament manufacturer recommendation.
When you say the backside is OK, you mean that there is no step shift? I.e., if it is a step shift, you should see more material in one side than it is on the other. However, the shift is too large to be a simple shift. Have you printed this gcode file previously? This can be an issue with your slicer that is generating a corrupted gcode file. Check the preview of the print process in your slicer to ensure that there is no layer shifting.
The filament is probably wet. These bubbles, like little pimples, are usually caused by a wet filament. The moisture boils and create these imperfections. Sometimes overextrusion also causes these type of imperfections, but they tend to be more pronounced than the ones in your print.
The temperature might be a little off as well. Probably too high. Check the filament manufacturer recommendation.
When you say the backside is OK, you mean that there is no step shift? I.e., if it is a step shift, you should see more material in one side than it is on the other. However, the shift is too large to be a simple shift. Have you printed this gcode file previously? This can be an issue with your slicer that is generating a corrupted gcode file. Check the preview of the print process in your slicer to ensure that there is no layer shifting.
Looks like either the printhead or the print, or both, moved around while printing. I mean, thats so severe looking stuff it's not some minor thing but something seriously off for a while.
For the other blobs all around the device are likely seam settings, try scarf joint. If not, saw recently a youtube video where similar blobs appeared because print head stopped for small moment every now and then, because of model with high resolution mesh didn't fit to memory or something and it basically had to stop to do computing 🙂
I've been printing for a month or so, not too many kilograms of filament under my belly, but all kinds of issues seem to emerge all the tine and one just have to work them out. These are quite fiddly devices, far from plug'n play 🙂 Do all calibration procedures, and prepare to have different settigns for different prints.
For the other blobs all around the device are likely seam settings, try scarf joint. If not, saw recently a youtube video where similar blobs appeared because print head stopped for small moment every now and then, because of model with high resolution mesh didn't fit to memory or something and it basically had to stop to do computing 🙂
I've been printing for a month or so, not too many kilograms of filament under my belly, but all kinds of issues seem to emerge all the tine and one just have to work them out. These are quite fiddly devices, far from plug'n play 🙂 Do all calibration procedures, and prepare to have different settigns for different prints.
Clas Ohlson filaments have a ton of quality problems. Some rolls are fine but the rest just have too much variation in diameter (or whatever) that produce lots of weird small glitches. Doesn't explain the larger shift though
Then I would say it is not a step motor shift. Check the preview in your slicer, specially at the layers that are producing the build ups.
How big is the excess? A fraction of a millimiter? One millimeter? More than one millimeter?
@dptucunduva the filament might be "wet" but the I don't understand why problems in the middle and not on the back side.
tmuikku the printer is new for me and I'm sure there's alot of settings to think about.
Earlier tries from the same filament roll were better.
Of course, the wet filament doesn’t explain the grotesque excess material; it would only explain the small bubbles present throughout the print. I was just pointing that out because it is a common issue.
Honestly I cannot think of a mechanical issue that would justify your problem. I would check the slicer first.
I have printed many waveguides with my old Monoprice Maker Ultimate ( Wanhao D6) and with a Prusa MK3. The Monoprice has inconsistent Z layer heights as is the case for many less expensive printers with cheap Chinese bearings, step motors and ball screws on the Z axis. So I saw problems like this on my Monoprice printers. I was able to fix a lot of it with lower extrusion rates and temperatures. The Monoprice was great for printing with ABS. ABS is excellent for waveguides as it is a bit softer than PLA etc and provides some damping.
Slower, cooler, extrude less, max fan.
What's happening is that outside surface is not getting consistent extrusion and likely isn't cooling enough. What to do.
1) In the slicer, look for a setting that lays down the outside perimeter of each layer first. Check that it is printed first on each layer with the viewer after slicing. If there is over extrusion happening for any reason on a layer ( Z screw variation ) on thin layers the material builds up such that there is no room left for that outside trace to go, so it bulges out. Laying down the outside edge of each layer first guarantees that it won't bulge outwards.
2) Some times the shape of the print changes the airflow pattern from the fan so the part isn't cooled properly in some places. So fan 100% and slow down to allow the layers to cool. It can also help to just lower the nozzle temperature so there's less heat to remove. High nozzle temps can mess up surface finish.
3) Lower the global extrusion rate. Usually there is a percentage you can adjust. There is too much material being extruded when it pushes out like that. If it's 100%, drop it to 90% or until you see gaps form between traces and then increase it a bit at a time.
4) "Earlier tries from the same spool were better". That happens as a spool takes on water. Store your filament in a zip lock back with several desiccant packets and a Humidity Gauge. A cheap food dehydrator will dry the filament and the desiccant packets in a few hours. There are lots of youTube videos on how to do it and what temperatures to use. I shoot for 15 - 20% humidity before printing. These guys you see in pictures with open spools all over the place live in high altitude desert conditions, or they would get total garbage prints.
5) Picky details, the little blips at the start of each layer can be tuned with some trace start /stop parameters in the slicer.
I ultimately started printing my waveguides standing upright with the Prusa on the print bed in two halves. With the layer lines going horizontally it was easier to get a good finish. A low cost printer will cost you a fortune in time, "upgrades", repairs and failed prints. I highly recommend going with a very top rated printer like the Prusa or Bambu lab. I wasted years upgrading and tuning on that dumb Monoprice printer.
Horizontal print orientation, ABS on Monoprice (Wanhao D6) heating the chamber. There are layer start/stop lines that look bad.
Vertical orientation PLA on Prusa printer. The stringing comes off easily. Layer start/stop points are moved to rear corners of print.
Slower, cooler, extrude less, max fan.
What's happening is that outside surface is not getting consistent extrusion and likely isn't cooling enough. What to do.
1) In the slicer, look for a setting that lays down the outside perimeter of each layer first. Check that it is printed first on each layer with the viewer after slicing. If there is over extrusion happening for any reason on a layer ( Z screw variation ) on thin layers the material builds up such that there is no room left for that outside trace to go, so it bulges out. Laying down the outside edge of each layer first guarantees that it won't bulge outwards.
2) Some times the shape of the print changes the airflow pattern from the fan so the part isn't cooled properly in some places. So fan 100% and slow down to allow the layers to cool. It can also help to just lower the nozzle temperature so there's less heat to remove. High nozzle temps can mess up surface finish.
3) Lower the global extrusion rate. Usually there is a percentage you can adjust. There is too much material being extruded when it pushes out like that. If it's 100%, drop it to 90% or until you see gaps form between traces and then increase it a bit at a time.
4) "Earlier tries from the same spool were better". That happens as a spool takes on water. Store your filament in a zip lock back with several desiccant packets and a Humidity Gauge. A cheap food dehydrator will dry the filament and the desiccant packets in a few hours. There are lots of youTube videos on how to do it and what temperatures to use. I shoot for 15 - 20% humidity before printing. These guys you see in pictures with open spools all over the place live in high altitude desert conditions, or they would get total garbage prints.
5) Picky details, the little blips at the start of each layer can be tuned with some trace start /stop parameters in the slicer.
I ultimately started printing my waveguides standing upright with the Prusa on the print bed in two halves. With the layer lines going horizontally it was easier to get a good finish. A low cost printer will cost you a fortune in time, "upgrades", repairs and failed prints. I highly recommend going with a very top rated printer like the Prusa or Bambu lab. I wasted years upgrading and tuning on that dumb Monoprice printer.
Horizontal print orientation, ABS on Monoprice (Wanhao D6) heating the chamber. There are layer start/stop lines that look bad.
Vertical orientation PLA on Prusa printer. The stringing comes off easily. Layer start/stop points are moved to rear corners of print.
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