User Origin not working? (fixing home position it was)

FabCreator Machine FabKit
#1

On my machine I have a slight offset between the home position (defined by the limit switches) and the actual 0/0 corner of the bed.
So when using lightburn with absolute coordinates ant placing a cut in the upper left corner, it will burn parts of the cut in the Frame.
As I understand the recommended procedure is to use “user origin”.
So I moved the laser in position (0/0 of the bed) and hit “Origin” at the cutter.
I place a design “somewhat in the middle”, select “start from: user origin” and do a “frame” to see where it will be cut.
What I expect:
laser head moves in the middle of the bed and draws a frame (where I positioned it)
What happens:
Frame starts in the left corner from the “origin position”
(is that a bug in lightburn?)
(Guess I will post that in the lightburn forum, too)

To put it in another way. Can I somehow set another absolute Position for the ruida board?
In the pic: the machine origin is where the red/green rectangle is positioned.
But I want the grid 0/0 be where the cross with the red dot is.
laser_origin

#2

It was in the ruida settings. The machine comes as a kit, but with configured home offset and I assumed that those would be fitting. So the trick was:
Move laser head to the actual 0/0 of the bed, set it as origin, move it to origin position inside lightburn. Use "get position from the “move” menu:
get_position
Now we have the values which to add to the existing home-offsets in the “Machine Settings” menu (in my case 3mm, so x=9.5 and y=25.5).
Write settings to the board.
switch the cutter off and on. (I closed and opened lightburn too, might be unnecessary).
This procedure is not explicitly mention in the manual, but it shows the home-offset value in the pics.
Now I can work with absolute coords without burning the Alu frame.

@FabCreator might be worth to add to the FabKit manual (would have saved me some time)

But I am thinking to move the home position 10mm onto the frame for one project:
engraving a ruler on the frame…

2 Likes
#3

Nice idea to engrave a ruler on the bed. Make sure you have the bed fixed with the thumb screws into a specific corner so you don’t lose the position if you ever remove it.
We had a lot of changes and challenges the past year, certainly some things to add and update in the manuals :slight_smile: Info about switching modes is a good idea to add to the manual as some people may perfear absolute coords

#4

thanks for the awesome information.