What's wrong with my printer?
Hi everyone,
I'd like to ask for help with the Z-axis brace I just printed. I'm up to my maybe 2oth print on my Mini+ and decided to print the brace in Prusament PLA. But, somehow a few layers towards the top of the print comes out weird with some surface imperfections/blistering all the way up the slanted part of the brace and only towards one edge. I've printed a benchy when I first got the printer with the included g-code file in the USB stick and it came out quite nicely. So this is the first time I'm encountering these rather glaring imperfections.
I've usually printed small parts with much less height, so this is probably the tallest print thus far. The rest of the print looks pretty good, at least to me. What could be causing these issues? Appreciate any pointers/help for troubleshooting this.
I've chosen the Prusament PLA profile in PrusaSlicer and only changed the infill to I think 50%. I've upgraded the extruder and heat-break to Bondtech ones soon after I bought the printer, and have been working well for other prints and filaments. One other thing, the printer does make a strange groaning noise during the Z-axis self-test at perhaps near the same Z height as the axis moves downwards, which I've yet to address.
Thanks!
RE: What's wrong with my printer?
That looks like some shifting probably because of the unsupported arm at an angle. You can post on the print comments to recommend some settings or you can paint some supports on that arm in the slicer to help the printer along. I chose the other brace cause I didn't want to mess with that one.
RE: What's wrong with my printer?
Could be also due to vibrations or other stuff that could move or disturb the printer. Personally I have had this problem but Muuch Woorse. Welp as much worse I mean the nozzle got clogged aaand it was a pain to change the old one to a new one
RE: What's wrong with my printer?
1) In prusa slicer did you add Bondtech extruder in the settings? I don’t have bondtech but I’ve read it needs to be reflected somehow in the gcode.
2) perhaps needs some supports
3) I’ve even read of one person that switched to an uninterrupted power supply and that fixed random errors they were getting on a print
Hope you solve the mystery!
RE:
If you ever saw how print looks if Bondtech extruder E-step setting is missing, then you would know that this is not the case here.
Also about "maybe support is needed". As can be seen from photo, overhang (printed angle) is constant and object was printed just fine, except the glitch at few layers in between. In short, has nothing to do with support.
For trying to help, besides having some experience, it's also important to pay attention on written details. Here, for example, OP says:
One other thing, the printer does make a strange groaning noise during the Z-axis self-test at perhaps near the same Z height as the axis moves downwards, which I've yet to address.
-until this is solved, it's pointless to guess for other causes. It's fundamental, that printer's mechanics is flawless.
[Mini+] [MK3S+BEAR]
RE: What's wrong with my printer?
@singlefin
For the strange z-axis noise take a look at this thread to see if it is related
https://forum.prusa3d.com/forum/hardware-firmware-and-software-help/z-rod-screw-grinding/
RE: What's wrong with my printer?
Thanks for all the feedback in helping me troubleshoot. After scratching my head for awhile, I decided to do tear down the Mini and re-build it to see if it was something during assembly that I overlooked. I have rebuilt the printer and in the process I think I fixed the Z-axis groaning issue. The trapezoidal nut should not be fully tightened into the mounting block. I did also try the threaded rod alignment/bearing attachment on the bottom of Z axis mounting plate, but read in a couple places someone strongly advised against constraining some free lateral movement of the threaded rod so decided to remove it.
I haven't had a chance to reprint a taller object to see if the Z-axis/trapezoidal nut issue caused the layers to shift in my earlier print. But, in the process of re-calibrating after the rebuild, I found another issue... the XY axis is skewed. This took 2 more days to troubleshoot and fix and finally now I have a more squared printer. Next thing on the to-do list is the strengthen/stiffen the axis. Looks like this is a never ending path... lol
RE: What's wrong with my printer?
It’s a rabbit hole, but once you get it all tuned up then the printer won’t need anything like that for awhile! Keep at it