Something strange is going on with my laser that I can’t figure out. When engraving, the sides engrave well, but the middle does not, even on the same plane.
The machine is brand new, one week old. It’s a 60w thunderlaser nova 25. It’s my 4th machine so I’m not new to lasers.
I’ve done a TON of troubleshooting and fine tuning. The belts are properly tightened as well as the bearings. The laser is properly aligned. It’s not a focus issue. It’s not an offset issue. I slowed down the acceleration and jump off speeds. I slowed down the engraving speed to 300mm from 450mm, which doesn’t fix it and wouldn’t be a viable solution if it did.
I changed from a usb connection to cat5 and also have sent the job to the laser rather than just running it…No dice.
I read a post similar to this in the forum and Oz said it could have something to do with ionization of the laser tube. I have no idea what this means. How would I check that and how would I fix it?
The machine is using an extension chord because it doesn’t reach an outlet where it is, could that be an issue?
Other than that, I’m stumped. Any suggestions would be appreciated.
You can see the blurriness in the middle compared to either side. It isn’t as pronounced as it was before all the fine tuning, but it’s still there.
Try slowing down the travel speed. The acceleration and deceleration on the edges may account for better results, while very high speed in the middle is too fast.
Drop your top speed by 10-20% and see if that makes a difference.
During a scan with a dsp, overscan is computed by the hardware. It will overscan enough to slow down, change directions and reach the specified speed by the image.
I’d say, put them back. Jump off speed is at what speed the motors start to turn before any acceleration is applied to bring it to speed.
Acceleration isn’t causal of this either… Lower acceleration values result in more overscan. If your acceleration is too fast it will lose steps. You will usually see the image drift, as a general rule.
If you’re scanning these, the head is up to speed by the time it makes the image where is has to lase.
You scanning offset is a bit off, but that has nothing to do with the engraving issue…
Material is sometimes and issue… with wood you see it vary by different areas of the wood pattern… This doesn’t appear to be caused by that issue.
It was scanning an entire row at once. So three of “testing 123” and the middle one was the one that is the issue. It doesn’t matter where on the wood I have it engraving, it has the same results, always lower quality on the middle “testing123”.
I found a major cause of the issue, which was the laser head had a very slight shake in it. A very small amount, like 1 or 2 mm. When I tightened up the bearings more, it helped a lot. The bearings are quite tight now though, which I’m not thrilled about.
It’s at an acceptable state right now. Very slightly blurred in the center of the engravings, but hardly noticeable. I’m going to put my settings back to default and see where that takes me.
I saw a big dip in the center of my honeycomb table on my large 1300x900 laser. There was insufficient support under the honeycomb and using the whole surface as a vacuum table exacerbated the issue. I ended up reinforcing the table with a big bar of aluminum - you may want to use a block as a gauge and check the distance from the nozzle at left, center, and right of the table to see if there’s a bow.
