Cura end g-code to lower buildplate/z axis

[rotorhead 1]

I've just been searching and am amazed that this has not been covered before.......or I have missed it!

I was hoping to be able to set the end code in Cura to lower the buildplate by a smaller amount rather than all the way to the bottom. This is purely for making nice time-lapse end shots in Octoprint so there might be a better way of doing this but I have not come across that either!

On the face of it this seems simple enough by just using a relative command and then lowering by 50mm but this might cause a problem if I ever print anything fairly tall and the instruction will therefore tell the buildplate to try to go below the end stop. Would this be a problem on an UM2 or would it just stop when it hits the switch?

If this does cause a problem then my thought was therefore some kind of query to lower by 50mm unless the Z axis is already within 50mm of the bottom. Is there any way of achieving this?

I found this: prusa forum

 

thanks

[obewan 37]

It will stop when it hits the endstop

[rotorhead 1]

ah ok that's good. So I just need a command to move down by 50mm and then if it can it will and if it can't it will just hit the end stops and stop there?

[tinkergnome 927]

13 hours ago, rotorhead said:

So I just need a command to move down by 50mm and then if it can it will and if it can't it will just hit the end stops and stop there?

 

In general not, it depends on the firmware. All endstops are ignored during printing on an UM2 (for example) and any command that is received on the serial port (USB) is performed as is (in any case). Octoprint does not have such an endstop-check feature as well (AFAIK).

IMHO you can still use the idea, but you have to change the amount of movement in the end-script for very tall models. I guess, you will do this editing in any case or do you make a time-lapse video of every single print...?

 

Can't you use the Octolapse plugin for this purpose?

Or simply use your video editing software to add the last snapshot at the end of the video for a few seconds (i think, even the Windows Movie Maker can do this)?

 

[rotorhead 1]

51 minutes ago, tinkergnome said:

 

In general not, it depends on the firmware. All endstops are ignored during printing on an UM2 (for example) and any command that is received on the serial port (USB) is performed as is (in any case). Octoprint does not have such an endstop-check feature as well (AFAIK).

IMHO you can still use the idea, but you have to change the amount of movement in the end-script for very tall models. I guess, you will do this editing in any case or do you make a time-lapse video of every single print...?

 

Can't you use the Octolapse plugin for this purpose?

Or simply use your video editing software to add the last snapshot at the end of the video for a few seconds (i think, even the Windows Movie Maker can do this)?

 

It's a UM2 and running your firmware!

Yes you are probably correct in that just adding the end code as required might be the only solution - I just need to remember to remove it for large prints.

I've tried to make octolapse do this but I could not see a way - hence thinking that Cura would be better.

The problem really is that the bed drops all the way to the bottom and all the timelapse programs run on either time or z-movement as the trigger. It therefore needs to pause at the appropriate height in order for a photo to be generated to then make use of it in the post process. At the moment, my choices to end the timelapse are either the final layer (usually with the head in the way) or with the build plate home.