Lulzbot mini axis shifting @ 100% infill

Hi, I tried to print this in lulzbot mini at 100% infill, but after its gets to maybe 8 mm height the axis slowly changes until it totally changes. a picture is attached for reference. Does anybody experience this and has some solution?

Easy solution is not to print at 100% infill as it is not very helpful unless you have a specific reason to do so. For part strength you can watch different videos, but 100% infill is not very much stronger than thick shell (perimeters and top/bottom layers, say around 1.2mm) and around 40-60% infill.

The reason why it shifts is that the layers build up too much material and eventually the motors lose position as the extruder bumps into the extra plastic.

If you really want 100% infill you can try reducing the flow rate until this stops happening.

Another reason this can happen is if the material isn’t laying down well, for example if you print PETG too fast I’ve had this happen to me. I slowed down the print speed and this issue went away.

These two reasons are assuming your printer is calibrated well and works normally otherwise, and is not related to loose belts etc.

It’s easier to just calibrate everything correctly and not use 100% infill. It happens on all printers.

True 100% infill requires that your filament diameter be basically 100% exact and consistent, and your steps/mm be 100% exact (or slightly under… which wouldn’t be 100% infill).

Any excess filament extrusion from thicker filament or steps/mm being a little high is going to have to go somewhere, at 95% and below, there’s always some room between the lines for excess to add to infill. During 100% infill however, the only place is up (or grinding filament away with your gears). That upward excess extrusion will catch the nozzle and do one of a few things: Major overextrusion will make the moving nozzle tear the part from the plate early on. Moderate overextrusion will build up layer by layer until it prevents nozzle movement, causing layer shift. Very minor overextrusion will still build up over time, but sometimes the hot nozzle can melt its way through the overextrusion, and if the part is short enough, it won’t build up to cause layer shift.

Some filament producers throw anything between 2.85mm and 3.00mm into the same spools, and that .15mm potential diameter difference can be a 10% variance in cross-sectional area, and thus volume!

If you’re using cheaper filament, 90% should be great for most things, but even for filament with good quality control with a +/- of .05mm, that’s 2.8mm to 2.9mm in one roll, or a 7.3% variance in area. Very high quality filament with +/- of .02mm yields a 5.8% variance.

@scotchtape Thanks for the insight I will try to change the design and try to play with the setting. I want to print it for 100% infill because the one I print at 80% infill was cracked and it cannot hold air pressure.

@Wrathernaut Thanks yeah I notice some of the filament are attached in the nozzle. Thanks for this tolerance I will try play with this.