order of printing multiple items  

RE: order of printing multiple items

Hi Gary,

I believe that the items are printed in the order they are loaded onto the printbed...

so, If you load one item (Centre of bed), Move it to position 1
Load another item, or use the add item button, and move that to position 2
Load another item, or use the add item button, and move that to position 3
Load another item, or use the add item button, and move that to position 4
Load another item, or use the add item button, and move that to the vacant area, out of position
Load another item, or use the add item button, and move that to position 6

then move the item you put out of position, back to the  position for item 5

Auto arrange, scrambles the order of part placement... don't use it if you want to control the print order...   

Regards Joan

RE: order of printing multiple items

In a second test, it appears the items are printed in the order in which they were generated.  Because of the cables sticking out of the back of the print head, one has to print from the front of the bed towards the back, e.g.

9      10       11      12

5        6        7        8

1        2        3        4

The default obstruction radius in slicer was also set to 45mm, which is insufficient; should be 55mm for my mk3s

RE: order of printing multiple items

Ugh.  I had to terminate the second test, as it did not print in the order the items were generated.  So the original question remains, namely, how can I guarantee a specific order of printing so objects won't be wiped out by the cable sticking out the back of the printhead, or the printhead traversing across already printed objects?

I had laid out a grid of 20 items in the following order:

16     17     18     19     20

11     12     13     14     15

6         7       8       9     10

1         2       3       4      5

They are being printed in the order 1, 6, 11, 16, 17, 18, 13

So in spite of being laid out in a horizontal progression which would have printed fine, they were printed in a vertical progression initially, followed by seemingly random selection.  I need some way to force them to be printed in a specific order.  Thanks for any help/insights.

RE: order of printing multiple items

@joantabb

Hi Joan,

See my added note above.  They are not, unfortunately, printed in the order in which they are added.

RE: order of printing multiple items

I think this has been discussed before: and the answer was you can't place items front to back, only left to right. All because the slicer can't be told print order. You may want to search github for bug reports asking for this capability to be added.

A 2017 request for the feature.

https://github.com/prusa3d/PrusaSlicer/issues/486

RE: order of printing multiple items

@tim-m30

Thanks for the bug ref.

If I understand correctly, I could place objects right to left and they would print in that order, so if I place 3 objects at the far left, then 3 more objects to their right, all 3 on the left should be printed before all 3 on the right.

That will work if I can somehow get a front to back order for each of those "columns", which may work given what I'm seeing.  I will try that, thanks.

RE: order of printing multiple items

Good luck, 
Hope you sort it out! 

and report back here what you did! 

regards Joan

RE: order of printing multiple items

Ugh.  This time I laid out a grid of 20 items in the following order:

4    8  12  16  20

3    7  11  15  19

2    6  10  14  18

1    5    9  13  17

They were printed in the order 1, 5, 9, 13, 17, 18, 19, 15, 14

So in spite of being laid out in a series of columns from left to right, which would have printed fine if each column were printed in order (individual columns would have had to be printed front to back), or if the rows were printed from front to back with the individual rows being printed either left to right or right to left, they were printed front row first, left to right, and then seemingly random.  When #14 was started it crushed #15.  Ugh.  It appears you can get a single row of objects to print fine, but not a grid.  I may try a 2-row and a 2-column layout and see if at least those will work.

RE: order of printing multiple items

Perhaps I'm misunderstanding, but I'm able to control the order of parts being printed. I Drag individual STLs to the bed in the order that I want them printed. This means I have to drag 9 STLs and place them for 9 models. Increasing copies will not work. I've renamed them in the parts list in the pattern below:

I'm able to drag the parts around to different bed positions and they will still print in the order they were loaded. I've attached a 3MF project file with this example.

RE: order of printing multiple items

Trying to embed a video.

Sequence 1

Sequence 2

RE: order of printing multiple items

Posted by: @bobstro

Perhaps I'm misunderstanding, but I'm able to control the order of parts being printed. I Drag individual STLs to the bed in the order that I want them printed. This means I have to drag 9 STLs and place them for 9 models. Increasing copies will not work. I've renamed them in the parts list in the pattern below:

...

I'm able to drag the parts around to different bed positions and they will still print in the order they were loaded. I've attached a 3MF project file with this example.

Attachment removed

Ah-ha!  I was using the copy button.  Will try adding additional copies of the same stl.  Thanks.  That counts as a bug for sure.

I just hand-edited the gcode of my 10x example to change the order and that seems to be working, but adding stl files instead of editing gcode is a big win 🙂

RE: order of printing multiple items

Thanks Bob --

Whenever I've tried to intentionally make parts print in a preferred order, I never found a reliable method (and I tried most everything); maybe the changes in Prusa Slicer from PE fixed something in the planner so it now follows a sequence based on the part list.  

RE: order of printing multiple items

They seem to be doing a lot with the interface, so perhaps we'll be able to re-order things soon. Sounds like big updates to PrusaSlicer are coming in October. 

RE: order of printing multiple items

once sliced you can go to the bottom and show the travel of the nozzle. Its a poor thin blue line but it is possible to check which part is being printed in which order.

RE: order of printing multiple items

Bob's advice to import the stl multiple times instead of using the copy button worked for me.

@robin-a, how do you determine the print order from the nozzle travel?  I don't understand because there is no way to get a time sliced depiction.  Isolating layers just shows that the nozzle hits everything on that layer, but not the order.

RE: order of printing multiple items

Unfortunately, Prusa removed the 2D gcode view from PrusaSlicer. It was invaluable for this sort of troubleshooting. I keep ideaMaker (free) installed for accurate gcode viewing for exactly these situations. Simplify 3D ($) also works well. 

RE: order of printing multiple items

Pronterface has a gcode viewer that seems to go in gcode line steps, not full layer steps. If you have a Prusa release package that includes Pronterface (Windows does, I'm not sure about the others).

RE: order of printing multiple items

@gary-a2

You will see a blue trace line on the sliced image on the screen. The long lift points at the end of each print can be seen and the direct nozzle path to each part can be seen

RE: order of printing multiple items

I don't know if this question is still alive, but i can manipulate the print order as i like.

No matter what order you insert your objects, when all settings are finished, rearrange the list on the right side with drag and drop before generating the g-code, and it will print in that order.

PS.:

You don't need to start the print, there is a good simulator for g-code simulation, to test your setup!