bevel cutting, would like help 1

[lasermen]

We are having trouble cutting tube with much bevel. The cut tends to burn away the top edge. Any help or cut conditions. We have a mazak space gear 2.5kw.

 

[chadxyz]

Have you tried pulse cutting the section that is giving you trouble? How thick is the tube, what angle is the bevel, is it mild steel, is it round or square??? I would need somemore details?

Chad

 

[lasermen]

It is 5/16 thick material on a 4x3 rec. tube.

 

[JayMaechtlen]

I wonder if you need to compensate the focus?
Look at the standoff with the head tipped, and figure out where the focus (beam waist) actually is. It may be focussed on (or near) the near edge, and way out of focus on the far (sharp) edge.

If you are cutting a similar bevel all the way around, can the head track/turn so that you could make the tip of the nozzle bevelled? Maybe that would keep a better coverage of assist gas on both sides of the cut?



Jay Maechtlen

 

[caren]

We have a SpaceGear48, that I have been running for approx 3 years.
I havn't found many solutions to the problem you mentioned.
As you start cutting bevels, your material thickness increases so your cutting conditions have to compensate for that(ie more power,slower feed rate.)but as the angle off attack incresses the edge thickness decresses, so the edge over heats and blows away. Sound familiar.
You can try using Nitro as an assits gas,to stop the edge oxidising but it is a bit tricky to keep the cut dross free.
Generaly you can't cut any bevels more than 45deg.
You might want to contact Mazak directly, for cutting condition. There engineers have done it all before, and at times can be quite helpful.

P.S. If you are cutting Stainless Steel, watch out for reflected laser light when bevel cutting.

Regards.