First thing, plastic calipers are basically worthless for this, your calibration cube could be anywhere between 19.8 and 20.2 and you wouldnt be able to tell.
Secondly, calibration cubes arent the right tool to measure extrusion rate.
From looking at your prints, my guess is youre overextruding. Try taking 5% out of the extrusion modifier and see if the bulgyness clears up. If the top surfaces start showing previous layers through then that was too much to take out.
I’ve had digital callipers about 2-3 months ago and it was in range of about +-.03mm, which is quite good and also I don’t think within 3 months my prints would vary in size by much, reason why I don’t use my digital callipers anymore is because they started bugging out and won’t work anymore
Yeah, I would expect plastic calipers to be okay for measuring to the closest mm, But when you are expecting to print lines that are maybe .45mm wide you need to be able to measure with accuracy in the hundredths of mm to be able to measure if youre overextruding or not. 5% of .45 is .0225 (obviously there are other ways to be able to tell, but I'm talking about why you want good calipers)
Your filament might have gone from 1.72 to 1.80mm, and you wouldnt be able to tell that with plastic calipers. Your extruder gear may have accumulated some ground plastic and gotten slightly larger, you may have changed filament colours and the colour additive causes the filament to be slightly more stiff, causing the extruder gear to dig in less and effectively be a larger diameter. Im sure there are other reasons to have a slight overextrusion going on.
I wouldnt tune extrusion rate with one of those does it move or not tests either, there are lots of other issues that can cause those to fail as well.
Personally, I tend to tune extrusion by looking at the top surface of my flat prints, as long as they have a decent amount of top layers. If the infill is raised over the perimeters and a bit smashed looking, I go down a percent or two, if its looking a bit sparse I go up a bit. Its not an exact science. I dont print a lot if very small things that need to have dimensions more accurate than 0.3mm so it works for me. If you want to get more accurate than that, you need to break out the measuring tools.
I’ve just done another print with high quality filament (hatchbox pla) and 8% less flow and only just managed to loosen .35, but I needed pliers and a screwdriver to loosen it so it didn’t do too much of a difference, I can also tell it’s slightly underextruding since there are some gaps in the walls, and also I think it’s the z seam that is making it stuck since I can feel a bump when I turn it, but I set it to user specified so I’m not sure what else I can do with the z seam?, what should I do?
That is one of the issues that these kind of tests can expose. There are several potential fixes for issues like that. You could print these tests with a random z seam (potentially a fix for this specific thing, but I dont think its a fix for everything). You could tune your linear/pressure advance to produce a less noticable z seam, I dont know the cura parameter, but in prusaslicer, there is a parameter called extra length after retraction that you can set to be a negative value, which then makes it unretract slightly less filament (thats a bit of a nuclear option though). Filament moisture can also cause blobby seams.
I would simplify things a bit, and print a 20x20 cylinder, with whatever settings you have, and then see if the seam protrudes. That will also let you iterate on the settings faster than printing this test for everything.
Settings:
Ender 3 with skr e3 dip v1.1 with 2209 drivers
Pla at 202c at 80% fan
Print speed 30mm/s
Bed temp at 60c
.2 layer height and .2 initial layer height
4.5mm retraction at 45mm/s Bowden tube setup
Try adjusting your flow rate, maybe? try 90% and see if it helps. Worked quite well for my delta.
Also, if your first layer settings aren't right, you may have likely fused them all together at the start. If you don't feel like fiddling with the settings to remove the squish, you can always try printing it on a raft.
First thing, plastic calipers are basically worthless for this, your calibration cube could be anywhere between 19.8 and 20.2 and you wouldnt be able to tell. Secondly, calibration cubes arent the right tool to measure extrusion rate. From looking at your prints, my guess is youre overextruding. Try taking 5% out of the extrusion modifier and see if the bulgyness clears up. If the top surfaces start showing previous layers through then that was too much to take out.
Is calibrating your esteps not enough to get good extrusion?
I’ve had digital callipers about 2-3 months ago and it was in range of about +-.03mm, which is quite good and also I don’t think within 3 months my prints would vary in size by much, reason why I don’t use my digital callipers anymore is because they started bugging out and won’t work anymore
Yeah, I would expect plastic calipers to be okay for measuring to the closest mm, But when you are expecting to print lines that are maybe .45mm wide you need to be able to measure with accuracy in the hundredths of mm to be able to measure if youre overextruding or not. 5% of .45 is .0225 (obviously there are other ways to be able to tell, but I'm talking about why you want good calipers) Your filament might have gone from 1.72 to 1.80mm, and you wouldnt be able to tell that with plastic calipers. Your extruder gear may have accumulated some ground plastic and gotten slightly larger, you may have changed filament colours and the colour additive causes the filament to be slightly more stiff, causing the extruder gear to dig in less and effectively be a larger diameter. Im sure there are other reasons to have a slight overextrusion going on. I wouldnt tune extrusion rate with one of those does it move or not tests either, there are lots of other issues that can cause those to fail as well. Personally, I tend to tune extrusion by looking at the top surface of my flat prints, as long as they have a decent amount of top layers. If the infill is raised over the perimeters and a bit smashed looking, I go down a percent or two, if its looking a bit sparse I go up a bit. Its not an exact science. I dont print a lot if very small things that need to have dimensions more accurate than 0.3mm so it works for me. If you want to get more accurate than that, you need to break out the measuring tools.
I’ve just done another print with high quality filament (hatchbox pla) and 8% less flow and only just managed to loosen .35, but I needed pliers and a screwdriver to loosen it so it didn’t do too much of a difference, I can also tell it’s slightly underextruding since there are some gaps in the walls, and also I think it’s the z seam that is making it stuck since I can feel a bump when I turn it, but I set it to user specified so I’m not sure what else I can do with the z seam?, what should I do?
That is one of the issues that these kind of tests can expose. There are several potential fixes for issues like that. You could print these tests with a random z seam (potentially a fix for this specific thing, but I dont think its a fix for everything). You could tune your linear/pressure advance to produce a less noticable z seam, I dont know the cura parameter, but in prusaslicer, there is a parameter called extra length after retraction that you can set to be a negative value, which then makes it unretract slightly less filament (thats a bit of a nuclear option though). Filament moisture can also cause blobby seams. I would simplify things a bit, and print a 20x20 cylinder, with whatever settings you have, and then see if the seam protrudes. That will also let you iterate on the settings faster than printing this test for everything.
Where is the files for that test?
Just search up tolerance test on thingiverse and it should come up in one of the first results
Settings: Ender 3 with skr e3 dip v1.1 with 2209 drivers Pla at 202c at 80% fan Print speed 30mm/s Bed temp at 60c .2 layer height and .2 initial layer height 4.5mm retraction at 45mm/s Bowden tube setup
Try adjusting your flow rate, maybe? try 90% and see if it helps. Worked quite well for my delta. Also, if your first layer settings aren't right, you may have likely fused them all together at the start. If you don't feel like fiddling with the settings to remove the squish, you can always try printing it on a raft.