Is it hard to set zero with laser without touchplate ?
@Lumpy Well, Kris, I finally got to play with Lightburn today. I did get a few burns done, but my approach needs work. This is significantly different from routing.
I cannot get the laser to ādial downā so that I can get it set to where I want to start. When I press the button on the board, the light blinks, but the laser power does not seem to change. It still burns the wood. Likewise, in Lightburn. I finally found where to set it, but even when set to 0%, the laser burns. Did you have better luck?
Origin seems to be completely different than in VCarve. So far, I start the burn and very quickly move the wood to where I want it. I cannot seem to get it to start where I think it will. Back to the drawing (burning) board.
I have added a laser, too. Iāve added a few macros to UGS to turn the laser on to 5% power (still burns wood), turn off the laser, etc. So what I tried was setting X, Y and Z axes to zero where I wanted zero to be (i.e. the zero XY point in Lightburn, but that didnāt seem to work. So, then I tried positioning the laser where I wanted the XY zero to be and turned the LM control box off and on to set the Home Position to that point and also X and Y axes zeroed at the same point. This actually seemed to work. Once I had this all set I finally placed the wood I wanted to burn in place, fastened down and hit play.
One thing unique about using a CNC like the Longmill for Laser engraving/cutting is that there is a Z axis. I think that most dedicated hobbyist laser machines only have X and Y axes and probably behave more like a 3d printer with with homing switches to set X and Y zeroes. With one of these machines you would have to adjust the laser lens to focus the laser. With the Longmill Iāve been focusing the laser by moving the Z axis up and down rather than adjusting the lens. Once I have it focused I set the Z axis to zero.
@paullarson Paul: Iām glad to see that someone else has the same issue that I have about the laser burning no matter what the power settting is. It is still frustrating though.
Iām interested to read how you solved the homing issue. I may try your method as I canāt seem to get Lightburn to do what I want no matter what options I choose for zeroing the machine.
Iām also interested to read about setting Z0. I have not been setting it at all. I have the laser positioned about 2.75" from the material and I just leave it there without setting Z in the software. I figured - maybe incorrectly - that there is nothing in Lightburn moving the laser up and down, so Z0 is irrelevant. Do you find that Lightburn does move the laser up and down in Z? If so, what tells it how much to move it? Using a router, I set Z0 to the surface and set VCarve to cut to the depth that I want. I canāt get my head around how a laser works in this respect.
You may be right about not having to set Z zero, but Lightburn does have the ability to move the Z axis if you enable it.
You should focus the laser to get the smallest possible point of light. This is not that easy, but I think Iām starting to get the hang of it. The company I bought my laser from (Endurance) provided a thin business card size piece of black anodized aluminum to help with the focusing. It doesnāt instantly burn and flare up like wood so you can actually see the point of light (with laser safety glasses). Also, Iāve been using one of those cheap digital microscopes to look at the laser point. It works pretty well although itās a bit clumsy. They have quite a bit of info on the Endurance Laser website about focusing and more.
Focusing is important to get both highest energy transfer and best detail in whatever you are engraving or cutting.
@Lumpy, great writeup!!! I just got my laser, a bit different, but should work well.
Do you have the drawing for your laser mount available? Saves me from starting from scratch on one! 
Forgot to reply earlier, but thank you so much! I have to modify it a bit for bolt pattern on the laser itself, but this definitely helps!
Dave
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Hey Folks,
Just wanted to apologize for my absenteeism.
I had emergency surgery a few weeks back and Iāve been recovering slowly.
Kris
No apology necessary. Get well soon!
Holy Kris, great review. Just ordered my laser and Iāll be following along! Thanks for taking the time to do this!
Finally got around to setting this up and I ran through the wifi cutout tutorial on lightburn and seemed to work okay and I matched the settings in the tutorial video. What didnāt work was cutting out the piece from the plywood.
Iām using 1/4 inch BB plywood and I tried 20% to 80% power on the laser going 50 mm/s with 10 and 20 passes and it barely leaves a scratch. It certainly doesnāt cut through.
Any ideas? I tried exporting the gcode and ran it through ugs , I also ran it again directly through lightburn.
I dialed in the laser so it leaves a very fine point and itās about 2 inches above the plywood.
Any ideas?
@justinbouchardw, what wattage is your laser supposed to be? 1/4" is pretty thick. 50mm/s is pretty fast. I have a 10W laser and I cut through 1/8" BB ply in 2 passes using 100mm/minute at 100% power.
it āsaysā 5 Wattsā¦ To be honest Iām not even looking to cut through 1/4 inch. Iām just looking to engrave with it but I was hoping it could burn down at least 1/8 inch or even 1/16 inch. At 80% power and 20 passes at 50mm/s didnāt do much more then scratch it?
Oh and I think I use 50mm/m not per second - that would be fast.
I engrave at 1000mm/min and between 35 and 45% power. I probably get between 1/32"-1/16", but Iām not trying for any deeper, and thatās one pass. If my laser is 10W and yours is 5W then Iād suggest cutting my speed in half or doubling the power. If you have one of the Chinese lasers they are a bit infamous for not living up to their ratings so keep that in mind. The other key thing is have the laser properly focused to the surface of the wood. You want the smallest possible point of light. Obtaining this is not quite as easy as it sounds because the point can be quite bright.
Thanks @paullarson - I slowed things down today and ended up with a nicer job. finding that point is pretty hard. I now have a piece of wood as a āspacerā to quickly move the z axis. so I donāt have to refocus that laser.
Just out of curiousity - where did you get your laser from?