I am getting wavy lines in my burns and not sure why. I am running an Ortur LM 3 with their 10 watt laser. All three belts have equal tension. At first I thought the “Welded” option in the fonts options was on but that was not the case. As you can see it’s not every letter which adds to the problem.
Thank you, Duane
Mechanical issue in the frame.
Cut your speed by 50% - does the problem get any better?
Load this file, scale it proportionately to fit your bed and run it at high speed with just enough power to get a good mark on cardboard. Any discrepancies from the file will indicate machanical problems. Upload a photo of the results so we can look with you.
BacklashTest.lbrn2 (68.8 KB)
I’ll try that tomorrow. Sorry about the “made by” file. Not sure how or why I sent that one! 
I will run that test tomorrow and send you the result.
Check to see if one of the belts slipped out of the cogs (slots) on the sides. If so, pull the gantry all the way forward and while holding it against the Limit Screws, remove and replace both belts back into the slots to be sure they are in sync.
If the belts are in place on the sides, see if a set screw came loose on one of the two rear pulleys. There are two screws on each gear. Make sure one of the screws is on the flat spot on the shaft. You may not see a loose screw, so I always check with a wrench to be sure they’re tight. Blue Locktite is a good idea too.
Then, check all the belts for proper tension.
Here is the result of the test. This was at 400 in/min, two passes. Sure looks like a mechanical problem. Unless you have something else to suggest I am going to pull out the assembly instructions and go step by step to hopefully solve my problem.
Claude, the side were they are suppose to be and tension is good. I’ll check the gantry belt for tension and also the pulley set screws as I go through the whole machine.
Horizontal lines with waves in a sinos wave shows vibration, or “ringing”. Check your set screws that hold on the shafts. Those are tough to get and keep right. Is your table secure? Do you have a camera hanging off the frame that could be acting as a tuning fork?
Maybe a quick photo of you physical set up would help?
I slowed the speed and it did help a lot but still need to find the root cause of the problem.
Try to look past my mess! Need to do some spring cleaning. 
Did not have time to work on the machine yesterday and won’t until Monday it looks like. Here is a picture of my setup. The unit on the left side of the gantry is for running my 20 watt laser.
What speed are you running?
Top speed from data sheet is usually fairy tale catagory. My speedometer on my Altima goes to 140 mph - and that aint ever gonna happen unless it’s dropped from a cliff.
I suspect that you have a wobbly table or your frame has come loose -or- your laser head is loose on the gantry. The error does not manifest on the Y axis, leading me to the gantry/laser head as the source of the sinusoidal aberration.
Thanks Jim. I hope to check that out today but, I am leaning towards the set screws as the problem seeing as they are hard to get to!!!
