Hello Folks,
New poster here but have been using my X1C coupled with the AMS successfully for over a year without any problems, perfect prints everytime and absolutely blown away by the print quality.
However, over the past couple of days I have started to see an issue whereby the sharp corners of my prints are no longer coming out square and sharp. The prints are bulging at the corners.
This was noticeable to the point where I had to stop the print last night. Going back to look at prints I have completed over the last couple of weeks I can see a steady decline in the quality. It wasn’t noticeable at the time when the previous prints came off, but going back I can see small bulging in these prints.
I haven’t changed anything, same filaments, same slicer, same STLs, but seeing a definitive reduction in quality.
Last night I attempted to change the hot end and nozzle, as had read that this may be a cause. Annoyingly I snapped one of the tiny wires on the thermistor so have had to order some new parts, they will be here in the next couple of days so the printer is out of action at the moment anyway. Once this is fitted though I will have a brand new hotend and nozzle (I do print a lot of PLA-CF).
Im reluctant to change flow rates, pressure advance, etc, as I say the printer has been working with no issues for over a year and I don’t want to change software variables and end up chasing myself. I’ve never had to calibrate filaments (or even calibrate the printer, except from the initial startup out of the box and a factory reset I did some time back)
Im hoping the new hotend will fix things, but appreciate any advice others may have, or if you experienced similar issues and what you did to fix things?
Photos below showing the bulging corners.
If I understand your photos and description correctly, that corner bulging is classic under-compensated pressure advance. It happens when the filament keeps flowing for a split second after the toolhead changes direction. Even if nothing else changed, PA/K can drift over time because of wear in the extruder, humidity in the filament, slightly different batches, or even tiny changes in the hotend’s internal resistance.
A worn hotend or nozzle can make it worse, but replacing hardware won’t fix the root cause if the compensation is off. This is why the corners started going soft gradually — that’s exactly what happens when PA/K is no longer matched to the filament.
You don’t need to overhaul your whole profile. Just run a new PA/K calibration for the filament you’re using and test again. That’s normally all it takes to bring those corners back to what you were getting before.
Thank you very much for the reply.
Hopefully my new hotend assembly will arrive this week and I will look to run a PA/K calibration for my filaments.
I will keep you updated!
If you’re using the auto calibration feature before the print, pay attention to the line it prints right after scanning the test lines. That is the result line. If it’s choppy, it didn’t get a good read and the PA/K value will be off. It should be mostly smooth. Make sure to clean the lidar camera lens too. A dirty lens will throw readings off or cause them to fail completely. It’s not on that part that sticks out, it’s on the tool head.
Success! I changed the nozzle and ran the flow dynamics tests in Orca Studio. There was a very slight adjustment to the K value (was 0.2, now 0.25), no change to the flow rate figure (the “0” test panel still looked the best to me)
