I’ve had my K2 for a few months now and have had some beautiful prints come off it but I hadn’t really done any prints that take up a large percentage of the build volume in terms of width.
The warden wanted some large trays for her desk drawers so hubby to the rescue!
The trays need to be as near to 350mm x 350mm as possible and are a simple square tray with rounded corners and sides of around 50mm in height. Should be child’s play for the k2. Or so I thought!
I quickly sketched them up in Freecad (So I know the models are good) and managed to sit them on the build plate in Creality Print 6.01 at around 347mm x 347mm x 50mm.
I had a bunch of sealed eSun ABS+ which I know adds another layer of complexity but it is less than a year old, dry, from a reputable manufacturer and because its the plus stuff, less prone to warping. And hey, I paid $1,500 for the K2 so I shouldn’t be worried about using ABS right?
I used the Standard High Quality Profile in Creality print and left everything else stock standard. I even ran factory calibration before I sliced and printed as I know from my K2’s that edge to edge prints are the ultimate test so I wanted to take out as many variables as possible.
The first print started ok but soon failed on the first layer as it stopped extruding and was clearly way too close to the bed with massive ripping due to under extrusion. I aborted and added 0.1mm positive Z offset and went again. This one was better but clearly too high as the strands were separating. Aborted after a few minutes and repeated this process until I found a sweet spot around 0.075mm Z offset.
I ran what I think was about my 5th attempt and the first layer is still awful, perfect at the front, under extruded through the middle and separation at the back due to the nozzle being too high.
I’ve checked the bed level in Klipper and there’s around a 0.5mm difference across the entire bed but with no bias to a particular corner, the bed mesh is a bit “wavy” so it couldn’t really be compensated out through shims etc. Also, a tolerance of 0.5mm should easily be compensated out by bed levelling. Even my old Creality Cr-10s Pro can handle over 1mm of variance across the bed with it’s old faithful BL Touch levelling probe!
So at this stage, I’m starting to wonder if bed leveling is actually even working. The thing is going through the leveling routine and creating a new mesh so it’s registering the measurements, I’m wondering if it’s actually applying the compensation on the print. I can see the bed oscillating slightly when the print head goes the full length of the bed during prints so it seems to be doing some level of compensation, but to scrape the bed to the point it stops extruding tells me it’s not right even if it is compensating.
Is anyone else experiencing anything similar? Packaging was unmarked so I don’t have any reason to think there as any twisting in transit and decent size prints e.g. a full size 12 shoe, print flawlessly and I mean significantly better than my 1st gen k1’s and marginally better than my Bambu P1P so it is definitely only on prints that use a lot of the bed.
That leaves me thinking it’s a software/firmware issue
I’m going to crack out some PLA today and try with that to take the ABS risk out of the equation but I have low hope.
Anyone else having a similar experience or any guru’s out there that might be able to give me something else to try? I don’t really have many other ideas.