Misaligned cutting

[Label_Everything (Si Abbey)]

We have a 100w Prytec 1060 laser, I am having an issue while cutting.

When I send the file, (a mechanical box that opens with a gear driven set up. file has 89 parts) the laser starts cutting fine then it is like the material moves and the inside and outside of parts are not aligned.

I have tried sending the file out in smaller sections, using colour mapping, I still have the same issue.

If the laser cuts the inner and outer of each part together, I don’t seem to have a problem, but it often cuts the inner part and moves off to cut somewhere else on the table and comes back later to cut the outer of the part, by than it has moved, and the inner and outer parts no longer align.

I have spoken to Prytec but they seem lost as to what the problem might be, they have said Possible causes maybe, bearing issues, belt slipping or a software fault.

I have found a lot of loose screws and a loose drive cog, I have now tightened all of these, but the issue remains.

The controller is a RDC6445G(EC)

Prytec supplied Engravelab 10 software with the laser, I have it installed on two computers, I have sent it from the two computers,

and I get the same results from both, I also installed the trial version of Lightburn and get the same result when sent from Lightburn.

Has anyone seen this issue before?

[ednisley]

@Label_Everything

I have found a lot of loose screws and a loose drive cog, I have now tightened all of these, but the issue remains.

You have found a lot of loose screws, but a few more remain, probably in the Y axis drive, tucked into the rear of the machine where you can’t easily reach.

Some earlier discussion of the same issue:

Designs are flattened on the bottom of the image

When I import a .png file it looks fine in the software. But when engraving, the bottom of the image is a little compressed. It helps to put a point under it, so the design is not the lowest point, but isn’t there a better solution?

Holes not starting properly

Hey All, We recently just got our OMTech 150W installed and started in on some test cutting. We have had just frustrations with trying to get these holes cut properly. For some reason, our preview looks fine and all, but when we go to cut that first hole out, the machine does a small line then begins the circle and does not complete it. We triple checked out settings and this shouldn’t be happening. We have also noticed that when we begin the cut from our picked origin, the machine returns …

Slipping of text and image

[slipping] Hi, I am fairly new to lasering. I have a 60w co2 Ruida machine which is only 6 months old. I have been having non stop issues with it slipping. I have checked the belts and pully and everything is perfect. I have spoken with the company where we purchased the machine, and they advised to do a test back on there software, which seemed to be fine. I re tested on lightburn and it slipped yet again. I am wasting granite material, which is costly as you can appreciate, and I am hoping s…

And it might be electrical, if you have dual Y axis motors:

Print not maintaining square?

I tried printing some text and noticed shape didn’t look right. I tried to print a 20mm square and the first 2 sides are good then when it started the last 2 they are no where near correct. I’m running a generic rig with a NEJE 7.5W optical laser. Any ideas what I should look at? [20230605_221021] [20220515_194305]

Good hunting!

[Label_Everything (Si Abbey)]

Thank you for your reply, I have gone over the machine and checked all the belts, cogs and screws I can get to, I did check all the parts that run alongside of the tube, and they all seem tight and aligned.

I did also try to search for a similar problem, but did not see anything, thank you for finding these posts, I will give each one a good read through.

[ednisley]

@Label_Everything

try to search for a similar problem

The keyword you need is “backlash” and it happens a lot:

https://forum.lightburnsoftware.com/search?q=backlash

Mostly on tabletop diode lasers, but big CO₂ lasers aren’t immune:

https://forum.lightburnsoftware.com/search?q=backlash%20co2

They mostly have Ruida controllers, so there’s some overlap:

https://forum.lightburnsoftware.com/search?q=backlash%20ruida

Unfortunately, there’s plenty of precedent …

[jkwilborn (Jack Wilborn)]

@ednisley

“backlash” and it happens a lot

Any mechanical machine has backlash… the parts need clearance to operate… this clearance causes the backlash when pieces change direction… The more precise the fit or interface, the less backlash…

Doesn’t matter if it’s a screw drive, belt or whatever…

So, yes, I concur, it happens a lot

[ednisley]

@jkwilborn

Any mechanical machine has backlash

AFAICT, all the backlash they squeeze out of ball screw milling machines ends up in desktop lasers, with a little bit left over for the Y axis of CO₂ machines.

I’d enjoy watching that parade shimmy past …