Temperature and Retraction Calibration Issues

[rkondakjian 1]

Hello,

 

I am trying to troubleshoot why I am running into an issue when printing a tray to hold playing cards (decks of UNO, etc). 191423.jpg - First picture

 

The problem, or rather end result in earlier prints is under extrusion, which can be caused by multiple items, so I am going through the calibration steps one at a time, following Teaching Tech. The tray has a few slivers extending out at joints or corners (seen in the first pic and circled in red), which, as explained in other posts as under extrusion, but what I am after is what parameter or setting do I need to further investigate?

 

I am going back and forth between Temperature and Retraction Tuning. I am using Sunlu PLA which is recommended 200 - 210 degrees. I am running through the Teaching Tech steps, and currently running Retraction Test using the starting value of 40mm/sec with 6mm for 4 different temperatures, 200, 205, 210 and 215, but I increase my fan speed in 10% stages for each temp test 191050.jpg - Second picture

 

The 210 between 80% and 90% appears to give the best Temp results, so I move on to trying different Retraction settings - Nozzle 210 Bed 60. CURA Stand Quality defaults speed at 25 mm/sec and I first test distance starting with 5mm to 7.5 in +5 increments 191131.jpg - Third picture. 6mm seems to be the best, I move on to test varying speed

 

Nozzle 210 bed 60 retraction distance 6mm I set the speed 20mm/s to 65mm/s in +5 increments 191156.jpg - Fourth Picture - this cut off at the top, the cleanest look seemed to be either 30mm/s or 35mm/s - I chose 30mm/s for now.

 

I go back to my Temperature testing, but this time I want to test fan speeds in greater detail, starting at 82% and increasing +2% up to 100% 191222.jpg - Fifth picture - Nozzle 210 bed 60 Retraction Distance 6mm and Speed 30mm/s

 

The first attempt to print failed as the cooling fan seemed to be too much to allow the tower to adhere to the base, so I increased the bed temp to 70 and reran the test 191314.jpg - Sixth picture - is a close up.

 

I need to follow up on a few things - why do I get what looks like a clean print at 80% fan speed in my first tower when I start at 10%, but then when I start with the first layer fan speed 82% I get the same splintering in the inside lower right?

 

What causes those strings to splinter - what calibration setting do I need to look into next?

 

Here are the troubleshooting steps I have taken so far to try to find and address this:

 

Ender 5 Plus running Marlin 2.1.1 using CURA 5.4.0

#1 Frame Check - Everything is solid, and the printer is sitting on top of a heavy duty 2x4 and flooring plywood bench - there is absolutely no movement or shaking during printing

Printer is level in all planes as well, X, Y and Z plane

#2 PID Autotune - using Pronterface, set the Nozzle for 210 and bed for 70

#3 Extruder E-Steps - I have 2 places I can test the filament before the hot end, before the Bowden Tube at the extruder, after the Bowden Tube before the Hot End, and then with the filament running through the hot end. In all these cases I measure 100 Millimeters as called for with the G1 E100 F50 command

#4 First Layer - I am using the CURA Extensions Bed Level Calibration (the 9 connected squares) - I used the MARLIN Tramming Wizard and got all 4 screws (with Silicone bushings, not springs) to measure the same 00.00. I then ran Bed Leveling. I then baby stepped the Z Offset until the first layer at all 9 points were "perfect"

#5 Stepper Motor Driver Current - I laid a ruler on the plate lined up with the nozzle and using the menu moved the X and Y axis multiple times in 10, 1, and even 0.1 mm increments. I did the same with both the left and right Z axis motors - everything moves precisely as it should, and stays level, I also first made sure the gantry was the same height at both Z motor screws.

 

I appreciate any and all feedback of what to focus on next - how do I stop the splinters/under extrusion issue.

 

Thank you.

 

 

 

Edited January 7 by rkondakjian
Reference pictures

[Slashee_the_Cow 267]

Based on the pictures, the bits coming off don't look like underextrusion in the slightest, just not enough retraction (your pictures point out at low retraction distances and speeds they happen).

 

If it was underextruding you should be missing bits, not be getting free splinters added 😄

[rkondakjian 1]

Thank you for the feedback.

 

I was running another print of the card holder after applying the Retraction settings. Things became so much more obvious on a larger scale when the print actually finished going through all the layers.

 

Now there's value in what I just learned from this failed print - I had inadvertently left my infill at 0.00%. All four corner columns are merely the shell - a 0.4 mm wall. The good news from this completed print, I know for a fact my gears are 100% calibrated because the nozzle lined up perfectly with the previous layer for at least 50mm of Z travel. 😉

 

I also found I had a slight error/offset in my previous 10 stage tower, very minimal offset stacking the cubes in each layer. I created a new Tower to hopefully better mimic my project printing environment.

 

Now off to run more calibration tests with varying Retraction settings.

 

Thanks again for the feedback.

 

 

Retraction Tower Test.stl

[rkondakjian 1]

I think I found my problem - trying to do too much with one print. It appears Cura is not changing the Retraction Lengths using Post Processing -> Modify G-Code

 

The only G1 E- found in this code is the initial 6mm and 30 mm/s set in the Configuration.

 

While using the Post Processing commands does clearly provide me feedback on the LCD display that the Nozzle Temperature or even Fan Speed is changing, there is no way to detect the Retraction Distance changed at all. And after examining this G-Code, it's not there... 😡

 

So now back to running individual towers with individual fixed Retraction settings.

 

[GregValiant 1,252]

If your gcode is in "Absolute Extrusion" mode (and it looks like it is) then there won't be an E-7.  There will be an extrusion line like "G1 X111 Y111 E50.5678" and then a "G1 F2100 E43.5678" which would be 7mm less than the previous E.

Search the Gcode for "00 E" and you should come across the retraction and print lines.  The retractions will be "retraction distance" less than a previous E value.  They are always in the form "G1 Fxxxx Eyyy.yyyyy"

[rkondakjian 1]

Yes, I'm finding that in the code after doing a "LAYER:" search...

 

Running this test with my new tower still showed stringing and splinters, so I'm thinking the retraction distance isn't the issue, perhaps speed. Will rerun tests with Retraction Speed starting at 40mm/s and going up in 5mm/s increments.

 

Thank you for the feedback.

 

G1 X217.893 Y177.681 E590.74552
G1 X218.151 Y177.774 E590.75464
G1 F1800.0 E584.25464;[CAZO:G1 F1500 E584.25464:CAZO]
;MESH:NONMESH
G0 F300 X218.151 Y177.774 Z17
G0 F12000 X217.559 Y178.479
G0 X177.504 Y178.871
G0 X176.085 Y178.871
G0 X134.961 Y178.514
G0 X134.312 Y178.401
;TIME_ELAPSED:1492.495311
;LAYER:84
;[CAZD:
;RETRACTFEEDRATE 1500.0
;RETRACTLENGTH 7.0
;:CAZD]
;TYPE:WALL-OUTER
;MESH:Retraction Tower Test.stl
G1 F1500.0 E590.75464;[CAZO:G1 F1500 E590.75464:CAZO]
G1 F600 X134.406 Y178.306 E590.75909