Bug with the 2nd PrintCore switch hook?

[picaschaf 3]

Hi,

Yesterday I tried to pack the build plate full to increase the build time efficiency and nearly got a heart attack after the first layer when the print head stuck on the little hook on the right hand side which is used to move the 2nd print core down.

It seems like the back right corner of the build plate is not fully usable due to this design - despite in my opinion its very neat Loosing a little bit of space is not so much an issue for me, but shouldn't the UM3 (Extended) firmware prevent the head from moving along this hook when its not going to switch the print core? As a software developer I would call this a bug. Will this be fixed, or is it a "feature"?

Best regards,

Alexander

[picaschaf 3]

I rearranged my build so it fits and doesn't collide with the hook. You see the arm in the front, if I rotate it so that the long part is in the back and the "pointy" part in the front - same position - the print core switch collides unstopped by the system with the hook in the back right. Similar problem when I add to this model a 5 layer skirt with 1mm distance to the model the head will scrubb (far less violently than colliding with the hook) against the right rail. So the right 1,5-2cm (and around 3-5cm in the back) of the build plate is essentially dead. On the left side there is absolutely no problem.

Don't understand me wrong, in my opinion this is absolutely okay due to the print head design (which is still really smart and reduces the need of an actuator to retract the second core). But the firmware should cap the coordinates in order to prevent such bad crashes regardless what the gcode tells the machine to do. It would be a really simple fix (when relying on a calibrated X/Y axis, which we should be allowed to).

[tomnagel 123]

This feature is built into Cura. I believe from another post that you use another slicer, right? Maybe you can build this "forbidden zone" into your slicer.

But of course I recommend to switch to Cura. Do you print with PVA as well? Cura contains smart features with nozzle temperature control which is essential for PVA reliability.

[picaschaf 3]

This feature is built into Cura. I believe from another post that you use another slicer, right? Maybe you can build this "forbidden zone" into your slicer.

But of course I recommend to switch to Cura. Do you print with PVA as well? Cura contains smart features with nozzle temperature control which is essential for PVA reliability.

 

I've used Cura as well and I see the dead zone there. Most of the time I use Simplify3D and yes, I could specify a dead zone in the software. But in my opinion from a software developer view this should not be a software issue, but a firmware issue. Firmware should always prevent hardware damages caused by external interfaces (in this case the gcode) which should be always treated untrustworthy - even for the own tools.