fairly new to 3d printing here. Printing a light box for a litophane on a P2S with some silver glitter PLA I had some significant warping in my first attempt.
First layer nozzle at 230º, following layers at 225º. Heatbed 85º at first layer, 75 at following layers. All other parameters as default, 0,2 mm layer height, 15% infill, 2 walls. Had no problems printing smaller models with this configuration for this particular filament. Had a minor clogging issue before but raising the temperature both for the nozzle and the bed solved the problem (using smartfil silver glitter PLA filament)
Followed the instructions on bambu wiki and turned off the part cooling fan for the first 3 layers and turned the auxiliary fan down to 40% as recommended in the wiki.
Halfway through the first layer I got the nozzle obstruction warning and when checking the print realized that it had stopped printing smooth lines and left some odd blobs throughout the remaining first layer.
Since the filament wouldn’t extrude any further neither by simply pressing ‘problem solved’ after the error nor with a filament loading procedure after stopping the print, I realized I had some serious heat creep, had to take apart the extruder, extract the clogging with a heated hex key etc etc. Again, as recommended by the bambu wiki.
Made a second attempt with a lower nozzle temperature (220º), aux fan at normal speed and the part fan turned off for the first 3 layers. Same problem happened and I’m looking at taking the whole thing apart again.
Is there a reasonable way to sort my warping issue without preventive measures resulting into a heat creep? Any help would be greatly appreciated. Unfortunately I didn’t take any pictures.
You don’t say which printer. If it’s got an enclosure, leave the door open and the lid up/off. The problem is heat buildup at the top of the chamber, in the pre-extruder filament path. If it gets hot enough, the plastic softens. That’s not a problem for the part of the filament being pulled through the PTFE tube by the drive wheel, but the short section between the wheel and the hot-end can collapse, like an accordion, instead of pushing in to the hot-end, it bulges out and you get a blockage that can’t go in to the hot-end or be pulled out of the extruder.
PLA generally doesn’t need chamber heat or a hot build plate. Set the plate temp to 50ºC.
Warping happens because of cooldown of the extruded plastic. As it cools, it contracts, pulling inward towards the center, which tries to “peel up” the outer edges at the build plate. You can minimize the warping by minimizing the temperature deltas. Hotter build plate/chamber temp, higher extrusion temp, fans only when absolutely required. But as you’ve discovered, this can lead to extruder jams. So you have to go the other way. Lower build plate temp, lower chamber temp, lower extrusion temp, still minimizing fans.
The objective is to get the print in process from cooling down too quickly. Keeping everything as hot as you can or reducing temps to the lowest you can will both work.
Also make sure that your build plate is thoroughly cleaned (diswashing liquid, lots of water and a clean brush), keep your chamber temp just below 35° and consider painting a few mouse ears at the corners.
There’s more that can be done against warping (slow down, reduce layer height) but it is usually the dry filament, clean plate, warmish environment (but not above 35°C due to heat creep!) combo that resolves it most of the time.
I had just cleaned it thoroughly. Saw the mouse ears in the Bambu wiki as well (they call them disks, I think that’s what you’re referring to). Right now I have the filament drying for 12 hours and will give it another go. Thank you!
Dried the filament for 12 hours and set all parameters to default. Eliminated most of the warping. I’m printing a litophane light box and since the printer is only going in circles around the edges I decided to switch the print speed to ‘sport’ (124%). Funny enough the layers in sport mode look much smoother and cleaner. What is is that needs to be tuned here? Don’t know if the picture is clear enough but the first layers still have some layer lines and speeding up the print totally eliminated that.
I would not really tune anything further as it lools quite good
If you do however want to run another print, the right bottom of the pic appears to show a little detachment from the plate (maybe a fingerprint?) and the 0.2mm layer height is always out-of-phase on each layer (0.08, 0.16 and 0.24 are in-phase).
Particular layer effects can however be extremely difficult to resolve. Layer time effects like the “benchy hull line” are really vexing and from the pic, I do not think it is a serious enough defects to merrit going down that rabbit hole. Or entire cave system
As for improvememts from sport mode, I myself always slow down in case of issues. However, it.may very well be that you had to speed up to catch a sweet spot for the resonance compensation.
& 
Glad the key issue was easy to fix.
