Bambu Studio sends toolhead "off-plate", causes collision and layer shift

Hello, I found a bug in Bambu Studio.

I sliced a simple part that needed interface layers and saw that when the nozzle changed to the interface layers, the g-code preview sent the nozzle way to the left. It looked like this:

I thought it’s probably just a preview bug and printed it. I figured, at worst, the printer would know now to try to go there. But I saw that it drew the white line with the support material and then paused with some kind of error. I don’t remember which error, I think it was some kind of AI fault detection error. Note that the toolhead seems to be parked in the wrong place. I guess there was a toolhead collision just before this:

Not noticing the toolhead position, I thought: hmm yeah, that’s fine, it should be able to resume properly. I hit resume. Then I saw this massive layer shift:

I wanted my part so I investigated the slicer preview. The line goes quite far to the left:

You can see that this is plate 7. The line went to where plate 5 is, which is the left-most plate in this row of plates:

So I copied the part onto plate 9, which is the left-most plate in this new row of plates. The preview now looks like this:

This isn’t ideal either as it’s extruding in the air for some reason, but it was a minor error and I still got my part.

To replicate this issue again, here is plate 10 sliced:

I hope this issue gets resolved soon, my children demand more cakes to sell! (these are cakes to them, not railways :smiley:)

Studio Version 2.5.0.64

I wonder if it was some invalid geometry on those pieces producing the issue

Thanks for the suggestion. I just tested out that theory by taking 2 cubes and assembling them to make a simple overhang and got this:

Seems to be about the support material change.

can you upload that file to check it out? do you have some custom gcode?

Issue seems to be fixed on Studio v2.5.3.61 :slight_smile: