I’m running a heavily modified K40 with Smoothie and LaserWeb3. I’m seeing some very strange patterns in my engraving. I generally only engrave small spaces (see the photo with Mom), and when I do, this pattern covers the entire space. When I test engraved a large circle it pops up at the edge. When I do something larger than letters, but smaller that the 3" circle it comes in symmetrically from the edges (see the photo with the tops of the three avengers icons)It’s very odd. The pattern reminds me of a moire pattern. My mirrors are all tight, and I don’t have anything vibrating against the machine or the table it sits on. Because it appears at the edges I thought maybe acceleration/deceleration had something to do with that, so I played with the feed speeds in Smoothie going up and down from 4K to 20k. No difference. I’ve increased/decreased stepper voltage on the off chance the steppers weren’t getting enough / getting too much power. I’ve swapped out beds to be sure the bed I was using wasn’t causing undue vibrations. I’ve reflashed the board. I’m on a Mac. My next step is to try switching to my PC to see if there’s a difference, but I can’t get past “npm install” and my start menu decided to start crashing, so I’m doing a fresh install of Windows 10. I’ve made sure none of my equipment was sitting directly against the case or the table the cutter sits on and thus inducing some sort of vibration. I’m sort of out of ideas.
Have you checked to see if you have the latest firmware installed?
I do indeed have the latest CNC firmware installed.
Here’s the particular post I was referring to previously that had something to do with moire discussion: https://plus.google.com/u/0/108257646900674223133/posts/2mP6xqYF6Bf?sfc=true
Have you tried to generate Gcode from @Sebastien_Mischler ’s http://Raster.js module
@Yuusuf_Sallahuddin_Y Yes, thank you for that! I found it yesterday, and I made sure none of my equipment was sitting against the case or table. It’s such an odd problem.
@Alex_Krause Not yet. That’s the new LW4, stuff, right?
It is standalone as of yet until it is integrated to lw4 it has all sorts of things you can tinker with just to verify it isn’t a gcode generation issue
@Alex_Krause I’ll give it a try. Thank you. It’s just so puzzling to have this pop up all the sudden. And true consistency of the pattern is really fascinating.
@K1111 can you provide a pic. You reference one but I don’t see it.
Since it’s mainly appears on the edges for large areas I would agree that it looks like it might be coupled to acceleration/deceleration and PWM. I’m not using laserweb yet so I’m unable to really help from that end. Does the pattern or coverage change if you change the PWM? Not sure what setting that would be.
@Nedman by change the PWM what do you mean?
The pulse width modulation of the beam. I know laserweb handles this but I’m not sure what the settings are since I’m not using it yet. Maybe @Alex_Krause can provide more insight into what I’m talking about from the software side.
I’m wondering is it related to having black & white speed settings the same, since you previously referenced 300/300 if I recall correct @K1111 . So I wonder have you tested different speeds? I tend to use something like 200 (black) 400 (white) when I engrave, but have yet to test any engraving since a few weeks ago.
If you can share a gcode output file for one of these images you are working with I can test that specific file with my current settings & see if I get the same results.
@Yuusuf_Sallahuddin_Y I’ve tried tons of different speeds. I think all of the photos I have here were 300/175 or there abouts. I think I also tried 300/200. I’m not at home right now, but I’ll grab the file later and share it.
@K1111 Cheers. It’s just morning here in AU, so whenever you send I am likely to be able to have a go at it sometime today & see.