Issues with cutting - it's burning the wood

[oratoroeu (Carlos Faustino)]

Hello, so a friend of mine have a swiitol C24 pro and when I went to try his laser, it didn’t cut properly, for example, my e18 pro cuts perfectly at 300mm at 80% but with this settings his laser barely leaves a mark on the back. And when I put it to do multiple passes upping the speed, it was burning the wood, not just cutting… The wood started to burn really and it was with air assist and all… Can you tell me what could be wrong here? It sat still during a month or so but previously it was cutting just fine

[JimNM (James)]

Focus length. Make sure yours is set right.

[oratoroeu (Carlos Faustino)]

Yeah, the focus length is right, however, I figured that it only cuts well if it’s on the direction of the grain of the wood, if not, it simply doesn’t make a mark on the back side. If I slow down ou up the power then it starts to burn the wood to just cut it

[parsec (FerAS)]

If you´re using multi pass cuts check this:

Lightburn Super Trick

Hello to all. Instead of making multi-pass cuts in intricate details where laser burns the same segment over and over again and that sometimes leads to material burn… You can automatically make 1 pass cut plus 1 pass cut plus 1 pass cut and so on to let material cool a bit. Using Lightburn sub-layers like in the enclosed example. It take a few seconds more but gives much better results. At the end of the job start the job again (3 times in this case) or use cut job with 9 cloned sub-layers, …

[oratoroeu (Carlos Faustino)]

thank you, i’ll be ttrying that, thank you very much

[JimNM (James)]

The focus of the laser diverges quickly after it passes the optimal length. Even a mm or 2 mm will make a difference. If you focus on the surface of a 5mm piece of wood, the laser will be way out of focus, by the time it reaches the bottom edge.

[oratoroeu (Carlos Faustino)]

Thank you for your time