Input Shaper, under extrusion in rounded corners after long straights.  

RE: Input Shaper, under extrusion in rounded corners after long straights.

Which model file did you download? Downloading gcode or bgcode is always bad as it will not have been sliced for your particular printer and filament.

Is it only one corner or all of them? If one corner, it likely is on the seams. See this thread:

https://forum.prusa3d.com/forum/input-shaper-mini/under-extrusion-or-gaps-at-seams-with-input-shaper-settings-and-5-x-firmware/

Try some of the calibration steps listed there for improvements.

Otherwise, your print looks like it has variable extrusion all over. Have you checked the hot end PTFE tube and made sure the hot end is not clogged.

https://help.prusa3d.com/guide/how-to-replace-a-hotend-ptfe-tube-mini-mini_119449

Try cleaning the nozzle and / or a cold pull:

https://help.prusa3d.com/article/cold-pull-mini_126399

Try cleaning and adjusting the extruder, critical with the fast speeds used by input shaper.

Also, dry the filament in a heated dryer. It always, Always, ALWAYS makes things better with no downside. Almost every other change you make will improve some things and make others worse.

Regards,

Mark

RE: Input Shaper, under extrusion in rounded corners after long straights.

Posted by: @mark-3

Which model file did you download? Downloading gcode or bgcode is always bad as it will not have been sliced for your particular printer and filament.

I don't understand. I usually upload gcode with my models because I think the website likes it as it helps to show some stats like print time and filament used.

I did not download anything. 

Is it only one corner or all of them? If one corner, it likely is on the seams. See this thread:

https://forum.prusa3d.com/forum/input-shaper-mini/under-extrusion-or-gaps-at-seams-with-input-shaper-settings-and-5-x-firmware/

The shape has 4 corners. one sharp, 2 with a 2mm fillet and one with a 5mm fillet. The seam is manually set to be in the sharp corner for the bottom half of the print and in the first 2mm fillet corner for the second half to see the difference. The seam has been better too with the older versions but this is addressed in the other thread.

I printed one version with 3 pauses to take pictures of the intermediate layers (they are all in the model page). It looks as there is just barely any filament extruded around the slow corners. The fast straights are perfectly fine as are the corners without any long straights next to them.

Try some of the calibration steps listed there for improvements.

Otherwise, your print looks like it has variable extrusion all over. Have you checked the hot end PTFE tube and made sure the hot end is not clogged.

https://help.prusa3d.com/guide/how-to-replace-a-hotend-ptfe-tube-mini-mini_119449

Try cleaning the nozzle and / or a cold pull:

https://help.prusa3d.com/article/cold-pull-mini_126399

Try cleaning and adjusting the extruder, critical with the fast speeds used by input shaper.

Also, dry the filament in a heated dryer. It always, Always, ALWAYS makes things better with no downside. Almost every other change you make will improve some things and make others worse.

Regards,

Mark

 

I did a cold pull and and readjusted the idler tension in the extruder all according to the online manuals already.

The PTFE tube is under suspicion but before I take the hot-end apart I wanted to find out if this is a general problem which affects all MINIs and it will be addressed in a future update. In this case taking apart anything because of it would be a bad idea as this may be the source of other issues.

I just finished a print with the 0.15mm SPEED profile. the results are micht better but still not as good as I think it could be.

What puzzles me: IS-SPEED profiles are using a very high flow rate, right? That requires high melting performance. Esp. the fast straights. However.. these are as fine as they could be. It's the slower corners that are not working properly.

If just anyone with a stock MINI could print this in PLA, 0.20 SPEED profile and report back that the print turned out fine, then I can start taking mine apart.

RE: Input Shaper, under extrusion in rounded corners after long straights.

I did not realize this was your design and you uploaded it. In any case, a gcode file is only good for someone who has not tweaked their calibration. It is much better to upload the .stl and / or the original CAD file, and the .3mf if you want to include settings. I have compensation for input shaping and flow rate that applies to every print, so I have to slice everything myself and never used downloaded .gcode or .bgcode.

The hot end PTFE tube is really easy to swap and is basically a wear item. I have replace it several times. They give you a spare. I order a pack from them when I ordered filament to save shipping.

Unfortunately, I don't use PLA and don't have any on hand.

Regards,

Mark

RE: Input Shaper, under extrusion in rounded corners after long straights.

I printed it on one of my Minis, 0.4mm SPEED IS profile, Proto-Pasta PLA. Print came out what I would consider flawless—after I had two failed prints when the printer was just sitting there, not finishing. I finally discovered the PAUSE commands in the 3mf file and removed them ☹️

The corner seam is a bit bulgy but you only see it when you look for it. 

Prusa server seems on the fritz, wouldn't allow me to upload photos or attach them as a zip file, so I uploaded a couple to imgur:

https://imgur.com/a/EA0cNDw

https://imgur.com/5jxZLGe

RE: Input Shaper, under extrusion in rounded corners after long straights.

Thank you for your effort! and sorry for the confusion with the pauses. I used them to make photos.

@mark-3  I'll give my MINI a thorough makeover, thank you for your suggestions!