Did Cura kill my fan ?

[skint 61]

Hey All

Am I correct in assuming that if Cura displays all models as GREEN on the display, then all should be OK to print? If one of the models grey`s out then it would fail.

This layout was all Green and I thought it was safe to proceed.

I started printing Roberts cable chain.

However...during the printing of the main attachment and a bunch of the small lids as per that screenshot above, the print head collided with the central component causing and almighty smash and resulted in the steel cage that the fan is mounted on all bent up.

Luckily I was in the room at the time and heard/seen this almighty smash bang wollop and managed to abort it pretty quickly.The print head was jammed against that central component and was crashing against it.

I managed to bend the fan casing back to something like the opposite one and am hoping it is ok.

I have a small squeeking/grinding noise now coming from the " left to right " bar, there is no way this would of bent right?

 

[0235 24]

what order did it print in? i think cura will print in order of files imported, not the standard front right to back left?

 

[skint 61]

It printed Front Left to Right as shown in the second image, the "Crash" happened when the head was going back across to the left to print the next clip above on the second line, hitting the centre component as it travelled back across.

It has put a little bit of fear into me, as I thought that relying on Cura to "show green" was the right thing to do.

 

[jonnybischof 60]

...I managed to bend the fan casing back to something like the opposite one and am hoping it is ok.

...

 

Should be ok - that part is not critical for printing precision. It should be as air tight as possible (it's not 100% tight of course), just like the other one. But really nothing critical.

 

...

I have a small squeeking/grinding noise now coming from the " left to right " bar, there is no way this would of bent right?

 

It's definetly possible that the crash resultet in some axis misalignment (not necessarily a bent shaft, but maybe a pulley slipped out of alignment).

I can't go into detail here because I don't have an UM2, maybe someone else can help you with this.

At the moment, one of my gantry shafts is actually bent (probably happened when I manually forced the printhead around -> you shouldn't push the head but better the x-y blocks) and that does result in some noisy movement and bad prints (round shapes are... not so round...).

But as I said, it's probably just something that slipped out of alignment.

 

[aaronalai 2]

I thought someone posted something similar to this and Diad said it was a problem with a firmware update he rolled out. I tried searching the forums for specifics and couldn't find the thread I was looking for. I recall him rolling out two firmware updates in a short duration of time because of some bugs that caused collisions of the print head with either the clips and/or the build plate. Have you installed the latest firmware via Cura?

 

[illuminarti 18]

It's unlikely this is a firmware issue. The earlier collision issues were to do with where the head was positioned for maintenance tasks, causing it to crash into the clips and/or frame.

This is more to do with path planning during the print, putting it squarely in Cura's territory. That said, what version of Cura are you using, Skint?

 

[illuminarti 18]

Also, check that the two cross rods are still fully seated in the sliding blocks; there should be no gaps visible between the rod and the sliding block cutout that it sits in, and when you look down on the printer, the sliding blocks should appear parallel to the sides of the printer, and not angled in or outwards.

 

[illuminarti 18]

I was able to reproduce the issue, so I added it as a bug in the Cura issue tracker on github...

https://github.com/daid/Cura/issues/777

 

[aaronalai 2]

Nice job illuminarti! I'm sure your troubleshooting will help a lot of people in the future. I would have "Liked" your hard work but ran of out "Likes" for the day.

 

[skint 61]

Illuminarti Thanks for highlighting the issue on github. I`l glad it wasn't just down to me being a noob and planning the print badly.

As for the squeaking, its still there. Its not a major issue or concern, i`ll figure out how to get rid of it one day.

Thanks for the help guys !

Oh Edit: Cura is version 14.01

 

[hp-65 4]

There are indeed bugs in the planner code and this already

happened in older versions too.

I posted this a while ago

http://umforum.ultimaker.com/index.php?/topic/2405-13064-project-planner-failures/&do=findComment&comment=17069

and quickly fixed it by adding a "manual order of print selection".

The code in Cura (partly) does work on Ultimakers, with the fan(s) mounted at the side(s).

It completely fails on machines that have a fan mounted towards the negative y direction.

*whamm*

8-D

 

[Daid 306]

I was able to reproduce the issue, so I added it as a bug in the Cura issue tracker on github...

https://github.com/daid/Cura/issues/777

 

Good catch Illuminarti! Thanks for the detailed report, that really helps in tracking this down.

Fixed it:

Old path: http://i.imgur.com/RwHGzpL.png

New path: http://i.imgur.com/gkw99Dg.png

 

There are indeed bugs in the planner code and this already

happened in older versions too.

I posted this a while ago

http://umforum.ultimaker.com/index.php?/topic/2405-13064-project-planner-failures/&do=findComment&comment=17069

and quickly fixed it by adding a "manual order of print selection".

The code in Cura (partly) does work on Ultimakers, with the fan(s) mounted at the side(s).

It completely fails on machines that have a fan mounted towards the negative y direction.

*whamm*

8-D

 

I missed the reply there. Sorry (busy with tons of stuff, and forum is very busy).

Checking it out right now. I do have test machines with fans mounted in X+ and X-, but not in Y- (as that would hit the back of the machine. And it seems something goes wrong there.

Note that the code has been changed quite a bit (but still lacks a lot of comments) sinds your comment about it.

EDIT: Just tested with the fan on Y- in 14.02-RC5, this works, however, changing the head sizes requires a restart of Cura for some reason...