I have an ongoing problem with my SV08 where Obico (I assume that it is Obico but there’s no message from it) pauses the print after the initial layers are laid down. The nozzle will be covered with melted filament. It is not a random blob; it’s either a cone or a cylinder that covers the nozzle. See the image.
The problem started a week ago after a full month (I bought it in November) of quality printing.
This happens with PLA, PETG, and ABS. I’ve gotten a few very small sized PLA and PETG prints to work (notably a perfect 3DBenchy) but anything with several inches of plate contact ends up with the gooey nozzle.
It happened on firmware 2.3.3 and now 2.4.6 (the one released on 12/23 in case I got the version # wrong).
It happens after Z-calibration.
It happens with a generic printer.cfg (a few small changes listed at the end of this bullet). I used the new firmware update as an opportunity to start from scratch. I changed the driver_sgthrs values to 75 (the toolhead was banging on the gantry) and included G3D’s macros I have been successfully using G3D’s Orca profiles but reinstalled them to be sure I hadn’t changed anything.
Lastly, I have replaced the stock hotend with a MicroSwiss FlowTech. Please note that this same issue was occurring before I replaced the hotend and it continues with the new one.
I could go on and on with what I have tried but I will stop here in case someone sees this and knows the issue and how to fix it. If not, I can provide as much information as needed. I would take this to Discord and Facebook except the former won’t let me post because of the stupid phone verification issue and the latter because I am doing everything I can to avoid creating a Facebook account. Thanks! klippy.log (4.7 MB)
Obico only looks for spaghetti & will send a notification if it detects it.
From the notification, you can tell them if it was real or false.
The setting for this is in the main screen under the info & camera view.
In that pic, if your printing in black & have white filament stuck to the outside…you really need to clean the outside of your nozzle. PETG is notorious for this.
You can find a set of brass nozzle almost anywhere
Heat up the hotend & using tweezers & a brush clean the outside of the nozzle.
Such blobs may be a sign of nozzle too far from the board when starting to print. As that material must come somewhere from, and it’s unlikely the result of overextrusion, it’s most from filament not sticking to the print plate, or from objects coming loose because of poor adhesion - which can also be the result of nozzle height not properly set.
Some users did have problems with nozzle distance not set properly, even though the SV08 ought to be rather helpful in that respect.
I’d re-run Z offset calibration, maybe the probe is off now. Klipper also allows you to set Z offset manually, using the paper method.
The blob on the nozzle isn’t built up goo, it falls off once the nozzle cools down. However, the nozzle was a bit crusty so I cleaned it well with a brass brush and then ran some cleaning filament through it to make sure the interior was clear. Next, I gave it a good heat soak and then a z-calibration and it printed perfectly! So basically I don’t know what the magic sequence of events was but since it is now working I won’t complain. I will try ASA tomorrow and see how it goes but thank you all for the help!
This can be caused by printing your first layer to close or by over extruding. Try printing one layer of a print and stopping the print after the first layer is down. The layer should be smooth and should match approximately your first layer thickness setting. Double check your slicer settings for typos in flow ratio settings. You might also try checking your extrusion rate by measuring how much filament extrudes for each 100mm you ask it to do. The z offset is most likely the problem. Getting a consistent z offset can be kind of a pain. I usually print a 3 or 4 pass skirt so I can make sure the z offset looks good before the print starts. Check and make sure you don’t have the original unpinned Sovol nozzle. The original nozzles have been known to have the nozzle slug to push out and cause the nozzle tip to be to close or even fall out of the hot end.
I finally observed the behavior closer and think that I know the cause but I am not sure how to address it. I was printing a z-offset test before performing OrcaSlicer calibrations when the print paused about 3/4 of the way through the first layer. The screen display said that the print was paused and this time I noticed that the filament buildup was a result of it extruding the filament after it parked. I looked in the log and the event was “Filament Sensor filament_sensor: runout event detected”. I assume that I have an intermittent issue with the sensor. I’ll continue to troubleshoot it but any advice is appreciated!
Filament runout sensor are usually just a microswitch with a lever with a roll which gets pushed towards one switch state when filament is present, and by releasing the lever when no filament is present, the switch changes to the other state. Those levers are thin metal and bend easily. Fix ist simple too: Open the sensor enclosure, bend it into a position that it reliable switches when filament is inserted.
I say “usually” because I haven’t opened up the SV08 sensor yet, and I simply assume this to be the case with those too. Alternative detection methods do exist, but are at this time less common.
In addition to what @Bushmills says you can also do a test by inserting a piece of filament into the filament runout sensor and bypassing this sensor to print your model.
Well, I’m an idiot. When I installed the enclosure I never mounted the filament sensor (I moved the spool to the bottom/side). I am sure that the switch ended up getting deformed over time. I printed a new holder for the sensor but it is still misbehaving so now I am trying the trick of bypassing the sensor as described by mich0111. I’ll get it sorted!
While I may be an idiot, your advice about tuning has been very helpful. I moved up from an Ankermake M5 with the SV08 and never had to do anything more than minimal tuning with it. Not that it was perfect by any means! Having this issue has forced me to stop and learn about tuning and calibration and the ability to dig into an open source device and system is what drew me to the SV08 in the first place.
A wooden toothpick may be a good alternative to a piece of filament: they are slightly thicker, which helps if you bypass the sensor because of unreliable detection - the inserted piece of filament may be just as unreliable
The piece of filament was just as reliable. I removed the sensor because I am using a new roll and will be watching the prints. It is working great without the sensor so I will fix or replace it ASAP. Thank you all!
