Newbie- Paper cutting

[oneeye]

Hi all, when I try to cut paper or cardboard they take fire, which could be wrong? focal? exaust system? i m using a desktop 40wco2 laser . thank you

[SkipW]

You need air assist. Do you have that?

Skip

[oneeye]

Originally Posted by SkipW You need air assist. Do you have that? Skip

yes, but must i use nitrogen? cause i try air and the paper fire with one laser shot

[lamicron]

Maybe you are out of focus???

[MonoNeuron]

How much pressure are you using?
The hole in the end of the focus tube may be too big reducing the pressure. My setup has only about 10-15 psi bit it works good. Is your focal length more than 2" and if so it may be too far away for the air to blow out the flame.
You may need to extend the tube or increase the pressure.
If your desk top machine doesn't have an air assist I recommend you purchase a fairly good quality aquarium air pump (electromagnetic piston type) and strap the outlet tube close to where you cut.
Rich.

[MonoNeuron]

Oh, I forgot. Are you cutting fast enough?
If your not then you may need to speed up the cutting as this also helps to reduce the flaming.

[oneeye]

Originally Posted by MonoNeuron Oh, I forgot. Are you cutting fast enough? If your not then you may need to speed up the cutting as this also helps to reduce the flaming.

yes, i think the nozzle hole is too big, i ll try a reduction and test diference pressures.
ths for hints m8s

[bisjoe]

What settings are you using? With 40 watts you should be using a speed of 50% or more and less than 20% power.