Greetings! Please help me understand what the problem might be.
The photos show a defect on the part, as well as the displayed printing time for the filament layer.
I’ve noticed that if the layer printing time is longer in the slicer, this problem occurs on the printed parts.
What does this problem primarily indicate, and what factors might be associated with it?
I use machine translation.
To avoid creating an unnecessary topic, I also discovered another problem. And I need help determining which parameters this is related to and what this problem indicates.
I found extra and unfinished lines along the edges of the printed model’s fill, which are not present in the slicer.
During the printing of the bridges, strange behavior occurs in the flow: sometimes it flows in excess, and sometimes it is insufficient.
The lines appearing on your model are caused by improper Z-offset calibration.
Recalibrate your printer.
I calibrated this parameter, but it didn’t affect the bridge printing results in this case. Bridges and overhangs at large angles print with defects.
It looks like “intermittent underextrusion” is hapening.
Make sure the axle is centered in the feel roller - https://www.printables.com/model/1020013-sv08-fix
Increase spring tension on the feed roller
Check for filament tangling on the spool
Exactly what cardoc said about under extrusion. In the unlikely event his suggestions don’t fix the problem, the under extrusion could also be caused by a partially clogged nozzle, but cardoc’s suggestions are much more likely.
I like directly observing and verifying functionality. I’d use the Fluidd web interface to manually preheat the nozzle to the print temperature, place a piece of tape on the filament 100 mm above the the top of the extruder, manually extrude 70 mm of filament, then measure to see if there is 30 mm between the tape and the top of the extruder. If it’s 35 mm or more, it’s probably under extruding for the reasons cardoc described. Once you have the SV08 extruding 70 mm on command, your under extrusion problems should disappear.
It’s also possible that you have a bad extrusion multiplier set in a bad slicer profile. It should be close to 1.
Good luck!
Unfortunately, this didn’t help solve the problem. I tried doing the same thing as shown in the video, but there were no changes in the behavior.
The very first thing I’d do is extrude 70 mm of filament and verify that the extruder is extruding 65-70 mm of filament. If not, there is a hardware problem with the extruder that needs to be corrected, assuming the steps/mm parameter for the extruder motor is correct, which it probably is. The list provided by cardoc probably has the answer to your extruder hardware problem.
If you see a thin strand of filament extruding sideways from the nozzle, the nozzle may be partially clogged. If you see intermittent extrusion in surges the filament may be slipping on one side of the feed gear. You can also get a feel for the problem (literally) by using your finger to manually turn the extruder wheel while watching the filament extruding.
It seems as if you are trying to fix a hardware problem in software. Instead of adjusting parameters, making test prints and trying to infer the problem, I recommend a more hardware oriented approach to solve what is likely a hardware problem. Twiddling with numbers can cause problems if the machine configuration becomes corrupted by diagnostic changes that aren’t restored to their original values.
I wish I could teleport to your location and diagnose this myself. It would probably take a couple of minutes and would be more educational than trying to convey this in an online forum.
Thank you very much for your response! Yes, the invention of a teleport would clearly make life easier for many people.
I tried to follow your recommendation and instructed the printer to extrude 90 mm of filament. The printer extruded 8.45 mm with a PA value of 0.025.
The second time, I changed the PA parameter to the calibration value, which was 0.061.
I instructed the printer to extrude 70 mm of filament, and the printer extruded 69 mm.
For the third attempt, just like in the first case, I instructed the printer to extrude 90 mm of filament, and the printer extruded 87 mm.
In all cases, the printer extrudes less filament than specified in the command.
What could this indicate? Are there any parameters for the printer that can be adjusted to fine‑tune the settings for my plastic?
If you are commanding 90 mm of filament and the printer is extruding 87 mm, that’s not enough of a difference to cause under extrusion issues as shown in your test prints. That’s why I suggested extruding 70 mm and if it extruded 65-70 the extruder itself is functioning properly, and then you’re back to a problem such as slicer settings.
First layer extrusion problems are a special case. If the nozzle is too low, it’s essentially the same as the build plate causing a nozzle clog.
One thing I neglected to have you check is the grub (set) screws in the extruder. 2 on the feed roller and 2 on the sun gear on the motor shaft. You’ll have to dismount the motor to check the sun gear. Have paper towels handy the planetary housing is full of grease.
Initially, I think the problem may lie in the settings and errors in the slicer parameters.
I also noticed one oddity during the printing of the model’s edges.
The printer makes a slight shift during printing; this is even visible visually — it twitches when it passes over that area (I’ll show it in the photo).
Also, I decided to try a different version of the slicer. I’m using the recommended Orca slicer. I printed using version 2.4.2.
I installed the slicer version 2.0.0, which was included on the bundled flash drive. Interestingly, with the old version, using almost the same print parameters, the test model printed better and without initial defects. However, the model’s border had the same defect in the build.
I’m going to completely delete all settings and reinstall the slicer. And then I’ll try again to see what impact this will have on the print.
Done. I completely disassembled and inspected the extruder, and also replaced the new nozzle that came with the kit. I monitored the print head’s operation when I gave the printer the command to extrude filament at a flow rate of 22 mm³/s, сonsidering that during my prints I limited the filament consumption to 19 mm³/s. Visually, everything was fine — the filament came out evenly, the gears weren’t slipping, and the pressure roller had very small fluctuations.
But all this didn’t lead to any changes in the printer’s behavior.
I’m going to perform an e‑steps calibration. But I don’t understand what to do with PA, because its value affects the amount of filament the printer extrudes, as I’ve figured out from my experiments.
It seems I’m starting to understand the very nature of the gaps in the extruded filament.
Apparently, after printing the bridge, it sags slightly — not noticeable to the eye, but enough for the extruded filament not to stick to the layer and to move on after the nozzle. And then, when the mass of the filament accumulates and sags, it gets caught and leaves those thick streaks of extruded filament.
That’s why the printing goes normally at the edges, but further on, gaps and thick lines begin.
Pressure advance does not change the amount of filament extruded it changes WHEN the extruder starts an stops. The total number of extruder micro steps are not changed.
This is a result of poor build plate adhesion. There may be a dip in your bed too small for the mesh to see. Work arounds are 1) use the 1st layer speed function to slow the print speed, 2) raise the 1st layer filament temperature. 3) use the 1st layer flow rate to increase flow slightly.
Is that line a skirt, brim, or parameter?
Without seeing the g-code I’m not sure what the slicer’s goal was when it laid out those tool paths.
Why did printing stop? my assumption is than if printing had continued a print line would have connected to the jog on the inside of the curve.
