So, I’ve switched from a .4 nozzle to a .6 on my CR-10s, and put in a new Capricorn bowden tube annoyingly exactly as the same time as I’ve switched to a new roll of PETG in the printer. I’m having some issues with the print I’m currently running that I think might be under-extrusion, which could track as I have my compensation at 95% from a test with the original nozzle and tube.
I should redo my flow compensation calibration, right? I’m not completely losing my mind?
in short you will need to re-do a bit of everything really especially if you are running above stock speed for the machine. They normally have fairly conservative limits but if you have sped it up for your normal .4 you will need to reduce printing speed to compensate for the increase in volumetric flow through the nozzle. Are you slicing in cura or something else?
What is the current issue you are having specifically? can you post a pic of the issue?
It’s gotten better as it worked its way up the print (even if it is a bit mucky, this print is being sanded and primered anyway, so it’s not a huge issue), but it’s not looking the neatest it’s ever been.
If you have changed to Capricorn PTFE, you will need to retune retraction as the fit is tighter than default PTFE. There is less wiggle room in the tube so less retraction is needed to stop extrusion. The shorter retraction you can get without oozing/stringing the better as you reduce the drop in nozzle pressure. this can look cause un-even extrusion on the part, especially complicated geometries
the general extrusion looks ok for this. the walls look fine. might be a slight over-extrusion is anything. on top surfaces, over extrusion sometimes looks like under extrusion as the nozzle is catching the extra and dragging it about causing scaring.
I’d say don’t look at your extrusion multiplier until you’ve got everything else sorted out. The extrusion multiplier is a way of compensating for your problems rather than actually solving them. (And don’t get me wrong — it’s a legitimate way because you’re compensating for difficult and/or expensive problems.)
So what I would do* is set the extrusion multiplier to 100% and then… calibrate the e-steps, print a temperature tower and print a retraction test tower, and once those are done you’re ready to do a calibration cube and set a multiplier if necessary.
All the things that those tests are testing are affected by changing your tube and nozzle, so it’s good to have that baseline. If you’ve had your printer a while and you’ve still got stock parts , then you’re also compensating for the wear and tear on the extruder and hot end, because Creality don’t use the most durable parts.
*Actually there’s a lie there. It’s what I ought to do, but what I actually did when my Ender 3 started having exactly those problems (around its fourth birthday) was live with substandard prints and intend to do something about it, until I was given a new printer as a present. my suspicion was that it needed a new hotend.
Me again. The simpler thing I should have thought of is: make sure your filament’s dry. I find that in humid weather like this week, PETG gets noticeably stringy after about 24 hours out of its plastic bag.
