Beginning and end points not meeting

Hello. I am using LB with a Redsail X900 with a Ruida RDC6442S-B. The beginning and end points do not meet when using Illustrator AI files. When I create shapes in LB it appears to work fine. Is there a file conversion you recommend with AI files? Other?


What does the shape look like when selected? If Grouped, Ungroup and then try to just select one os the paths (sides). This will help determine if the shape looks correct but is really made up of distinct segments that are not connected.

How does the AI file look in ‘Preview’? How about if you zoom way in on the workspace? If the shape is not closed, try Alt-J (Auto-Join) to close shape.

The shape is definitely closed. Used the same file that I export to DXF and use in AutoLaser on a different cutter. The file also looks fine in LB but when I run it on my new Ruida machine, the ends don’t meet.

What are your settings for this cut? With Ruida controllers there is a setting called “Start Speed”, that when the speed is set ‘at or below’ this setting, the controller defaults to your min power setting. The default for this controller setting is typically set to 10 mm/sec.

To answer your earlier question, yes I checked it out in Preview and everything is connected.

Settings are 40 power and 11mm/sec speed. I could not find the Start Speed setting on the controller. Do you know where that lives?

For both Min and Max?

In rereading, are you saying when you create the same shape in LightBurn with the same settings, the cut is produced as expected with meeting endpoints?

Have you tried to run this AI file with the same settings in RDWorks?

Not in front of my laser at present but if I remember correctly when viewing ‘Edit’→’Machine Settings’ the Start Speed is found in the User Settings, Cut parameters. Although, now I don’t think this is the issue.

I am missing something here. @LightBurn?

40 for both min and max.

I did not recreate the same shape in Lightburn. I just created general squares and circles and they are connecting beginning to end.

I had never used RDWorks until 30 min ago. The cuts were perfect, beginning and ends meet. Engraving is another story but I guess I need to figure out the settings in that software.

If you would, please send this AI file along with the .lbrn file to support at lightburnsoftware dot com and reference this post so we can take a look.

The image you showed is the back - does the front look the same? I can’t think of any reason that an imported file would behave differently than a file in LightBurn. If it looks right in the preview, that’s the data being sent to the laser.

I took a quick look at the files you submitted, and I don’t see anything strange in the settings, but I did notice something about the file - it’s piecemeal, not continuous shapes in most of it:


If you ungroup the file content, very little of it is continuous shapes, and that’s going to affect the path planning. If the machine is skipping steps anywhere, it might be that the ends don’t line up because of this.

Run the auto-join tool to reconnect it all, and see if that helps. Ungroup everything, select it all, Edit > Auto Join selected shapes (or just Alt-J).

If that doesn’t help, then can you export a small section of the cut, like this piece:


Import that as an AI in LightBurn and in RDWorks, and use each program to produce a machine file? In LightBurn you use “Save RD File” and in RDWorks it’s “Output UFile” I think, but the buttons are nearly in the same spot. Send both files to me so I can check them for differences. If you can actually run them to verify that the machine output is different that would be good.

I showed the back side in that image because there is much less burn marks on the back and the connected section is more visible.

I did extensive testing last night and I found that the gaps are occurring in both LB and RDW but to a lesser extent in RDW.

When I run a smaller cut just a square or random shape, I am not getting any issues with the beginning and end points meeting. It only seems to happen on larger cuts so I cut the entire file I sent you and there are plenty of points where it did not close or overshot the close point.

When I cut the same file in RD Works, I only had one instance of the same issue.

So even though it is less severe in RD Works, it is still an issue. So there may be an issue with the machine causing this drifting? Since I have never had this issue with my older machine, what are the steps to check on the hardware?

It looks like you’re losing steps somewhere, or it could mechanical looseness in a connection somewhere. Check things like the pulleys & pinions to make sure there’s no play in them, set-screws holding the pinions onto the stepper motors to make sure they’re tight, check the shaft coupling that connects the left & right sides of the Y axis together, and check that your belts aren’t loose. That’s where I would start.

The reason for the difference could be that RDWorks has an option to order the paths to try to minimize the effect of slop, and LightBurn doesn’t yet. If you have “Backlash Repay Optim” enabled on the User tab in RDWorks, that might explain it - even just changing the order in which various paths are cut will alter the appearance some, so it doesn’t need to be that theirs is “trying” to fix it; it might just be that the order in this case is better for your job.

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