printhead margins

[edwardlego 0]

i'm printing multiple very low objects (the nozzle is taller) and i want to put them as close to eachother as possible.

so i found a json file with the printhead margins and an inadequate explaination here:

https://ultimaker.com/en/resources/20511-change-machine-settings

i probably can't put all the numbers in part 7 at 0 or i'd run into problems, including the buildplate.

So my question is, which should I?

edit:

i tried some experimenting, but it is very tedious, each time i update the json file i have to remove the printer, restart cura and re-add the printer. i recently switched from 15.x.x version, if i'm not mistaken you could edit those settings on the fly in that version?

also, the last directory you imported something from is no longer remembered when you close cura?

edit 2:

so far, adjusting any number makes the margin around an object almost disappear completely, so i can't figure out which numbers represent which dimensions.

edit 3:

btw the 'ensure objects are kept apart' function now makes sure the areas where the print head moves don't intersect, while they should be able to do that safely under any circumstance?

i'm trying to fit a lot of things on the buildplate without the function enabled, but it's a hassle figuring out where the parts overlap too much, this was MUCH better in the previous version i used, why are a lot of good functionalities gone?

Edited September 11, 2016 by Guest

[ultiarjan 1,215]

The numbers in part 7 are the distance from the nozzle center to the outside of your printhead (including fans). So unless you physically made you print-head smaller, for example by removing the fans, you should NOT change these values. You normally change them f.e when you changed your UM head to an E3D head, of when you added a 2th fan to an UMO...

[edwardlego 0]

The numbers in part 7 are the distance from the nozzle center to the outside of your printhead (including fans). So unless you physically made you print-head smaller, for example by removing the fans, you should NOT change these values. You normally change them f.e when you changed your UM head to an E3D head, of when you added a 2th fan to an UMO...

 

i'm printing things that are 1.7mm tall, that shouldn't be able to touch anything, as long as the nozzle stays clear

[nallath 1,076]

In the old Cura you could ony define the size of your print had as a rectangle. In the new Cura you can define it to be any 2D polygon.

The machine_head_with_fans_polygon defines the entire size of the head.

[geert_2 543]

When I want models to sit closer together than Cura allows me to do, I multiply them in my 3D-editor (DesignSpark Mechanical) in the desired amount and positions. And then I export that combination as STL. Now Cura recognises this as only one object.

In this way you can put things as close together as you want. But then they will always be printed all together of course, and not one by one, since Cura thinks it is only one object.

Have you tried this approach?

[ultiarjan 1,215]

In the old Cura you could ony define the size of your print had as a rectangle. In the new Cura you can define it to be any 2D polygon.

The machine_head_with_fans_polygon defines the entire size of the head.

 

 

        "machine_head_with_fans_polygon":       {           "default_value": [               [ -44, 14 ],               [ -44, -34 ],               [ 64, 14 ],               [ 64, -34 ]

 

Just to be clear, the polygon is build up by connected points all relative to the nozzle center right? And how does it work with 2 nozzles? I only see 1 polygon in the UMO dual profile.

[nallath 1,076]

It uses what it sees as the center of the head, which could be the center of the nozzle. In most cases it makes sense to put the origin on the primary (or only) nozzle.