Distorted Benchy with banding 🙁 (first print)
Proudly finished building my new i3 MK3S+ and passed all the setup and calibration tests successfully. Then time for a Benchy for the obligatory first print and sadly it turned out pretty awfully 😫
There’s serious banding all around the bottom and things get worse from there…the top part of the print is distorted and the cabin bends in and out.
Don’t even know where to start troubleshooting 😢 Checked the belts using the self test and they’re at 248 for X and 276 for Y. Seems a bit tight for Y but can’t believe it’s enough to cause such severe issues…help!!
Printed using the silver filament that came with the printer and the pre-sliced Benchy that came on the delivered SD card.
RE: Distorted Benchy with banding 🙁 (first print)
At first sight, this looks like 'play' at the pulley on the x-axis stepper motor shaft.
The position of the grub screws with respect to the flat on the shaft is important - make sure they are correctly positioned and tightened (check the manual). Probably worth checking the same on the y-axis. Also, re-check the belt alignment across the x-axis.
Let us know what you find.
Cheers,
Tim
RE: Distorted Benchy with banding 🙁 (first print)
It is a mechanical issue for sure. Check you belts and pulleys.
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Chuck H
3D Printer Review Blog
RE: Distorted Benchy with banding 🙁 (first print)
Thanks!! Will check everything over…was super careful on the build but maybe something got loose 🙁
Gonna try printing a cal cube because it’s a lot quicker than a Benchy and easier to see which axis is impacted. Will report my progress in case it can help someone else!!
RE: Distorted Benchy with banding 🙁 (first print)
Ok…tiny 10mm test cube looks a lot better (without doing anything) but already displays weird behaviour so I think it’s a good quick test for now.
The Y-Axis side shows uniform narrowing towards the bottom but this could just be the elephants foot correction needing tuning.
The X-Axis side though shows a shift in layers for each of the first few layers in one direction. This is obviously not right so I’m going to focus my investigating on the X-axis for now.
RE:
your test cube shows you still have some adjustment to do.
check belts, not via software, check grub screws (set screws), check all screws. check that your your hot end is not wiggly.
RE: Distorted Benchy with banding 🙁 (first print)
Out of interest, did you generate the G-code for this calibration cube from Prusaslicer or is it a pre-cooked one from somewhere?
Cheers,
Tim
RE: Distorted Benchy with banding 🙁 (first print)
For the cal cube I generated the gcode using a fresh install of PrusaSlicer and I've got to say it already looks somewhat better than the Benchy (which was from the gcode on the delivered SD card) - which could be a positive thing or could just be because it's a much smaller and simpler model.
Either way there's definitely something up with the X-axis - based on the software measurement the belts are too tight..even the tensioning fine-tuning screw is not even pushing the motor at all and it's reading too tight. So tonight I'll take the back off the x-carriage 😖 and release a couple of teeth on the X belt as well as checking all the grub screws and the rest of the X gantry...hopefully that will improve things or at least eliminate some candidates. It's all good experience 😉 Will report back soon!
RE: Distorted Benchy with banding 🙁 (first print)
So…followed the instructions to take the back off the extruder and loosen the X-belt a bit and lo and behold - I’d forgotten to tighten the X-Axis grub screws during assembly 😫
Feel like a complete bumbling idiot but at least it’s fixed. Was too late to run off anything more exciting than another cal cube on draft settings. Obviously tuning to do but it’s looking a huge amount better…hopefully problem solved!
Massive thanks to all for the help, and especially @tim-weston who identified the problem immediately - you sir are a bona finde genius!
