Hot end stuck to the print, not sure what's going on

So I recently got a Lulzbot Mini (refurbished), first print went well. I then tried another, and it was turning out good. Towards the end, the part stuck to the hot end and was lifted off of the bed. I immediately ended the print, what do you guys think happened? I was printing with the basic Lulzbot Cura profile, at normal quality, no brim, with HIPS. Here’s a picture of the aftermath:

I tried cleaning the hot end after. When doing a test extrude, the initial filament would stick to the side of the hot end, forming a loop when the rest of the other filament came out. After a few more test extrudes, this stopped, but I am not sure if this is something I should worry about. Let me know if you have any ideas, thanks!

Edit: Tried it again, and it happened at almost the exact same time in the print. I am a noob, but I am guessing since this part has a relatively low surface area contacting the bed, it’s not sticking well enough, so I need to use a brim?

The Marvin should be fine without a brim… But give that a shot, it will definitely help adhesion.

It could be that to much filament is being deposited. Therefore the nozzle is scraping over the print. Spot check the diameter of your filament with calipers, then adjust the diameter in the slicing software, if necessary. Set the flow multiplier to .90-.95 to lower the flow rate also.

Thanks for the tips! Looks like my eSun filament is 2.9-2.95mm (I think the basic profile I was using was programmed at 2.85), is that a big enough difference to worry?

I tried changing the filament diameter to what my filament really was (2.92 about), same error at the same spot occurred. So I tried to reduce the filament flow percentage to 95%, and that print failed almost immediately. I don’t know what I am doing wrong! :frowning:

Hmm… So is the Marvin just coming off the bed during printing?

Maybe some tweaking of the z-endstop will help. A business card is a good feeler for setting yhe nozzle height. Move the nozzle to the middle of the bed, home the z-axis. Slide the business card under the nozzle. There should be slight resistance.

For prints with small surface area touching the print bed, try adding a -.1 z-offset in your slicer software. This will lower the nozzle after it is homed in z axis. Which should also help adhesion.

Have you tried the calibration print on the SD card? This will help gauge if your bed is level overall. After printing, pay attention to the adhesion strength when removing the pattern. Variations in removing the filament are tell-tale signs that the bed needs level. A dial gauge helped me evaluate the levelness of the bed.

Thank you for all of the tips! At one point in the print, the hot end was sticking to the Marvin and yanking it from the bed. A brim fixed the problem with this particular print, but I still think I could do further tweaking (maybe lower the hot end temperature?). This has only been a problem with HIPS for me, ABS and PLA have been good.

I will definitely try the things you mentioned though, thanks for your help! :slight_smile: