Best Way to Cut Steel Mesh with Plasma?

[ovrszd]

Try to keep the non-cutting time to a minimum. That eats nozzles.

Also, is your air dry?

Both very good points!!!

 

[Hilbilly]

I did try to keep the non cutting time to a minimum and that may be part of the problem because I moved very quickly from strand to strand but did not slow down enough during the cut to get all the way through so there was sprayback and I ended up having to do it a second time. Operator error.

I think my air is dry. I built a steel pipe condenser that air from the compressor flows into, before it goes into my air hose and at the end of the air hose, at the plasma inlet, I put an air filter plus there is one built into the 30XP. I never seen any water in the filter on the outside of the plasma. I used the same setup for the sandblaster and that seemed to work well. Although with the sandblaster the compressor was running a LOT and both the compressor tank and the steel pipe heated up. In that case I actually got a few drops of water in the filter at the blaster. The blaster had another exterior filter built into it and there was no sign of water in there.

 

[Industrial Toys]

Not sure I understand why non cutting time would be hard on a tip. I was told it's the starting, that's hard. And when you are not cutting, there is less heat coming back to the torch. How is the capacity of the device otherwise?

The worst mess I ever made of a tip was trying to make holes in a railroad rail! I guess it wasn't a gouging style tip.

 

[ovrszd]

The heated air going thru the tip is always cutting it and enlarging the hole, which makes for a sloppy cut. Imperfections in the tip will also cause this erosion to not be perfectly round. Then you have a tip that cuts at an angle of some sort.

I've never tried to gouge thru something that thick. I've gouged 1/4" a lot. Some 1/2". Nothing thicker.

 

[muddstopper]

Piercing metal with my spectrum 625, I start the arc and then lower it to the metal. It keeps the blowback to a minimum. For anything over about 1/4in thick, I like to drill a small hole first to start my cut so I dont have to perice. For gougeing, I like to keep a very long arc also. Not sure the number on the tips I use, but I know I cant use a long arc with a drag tip. Cutting expanded metal, I start at the edge and never release the trigger. I can cut thru about as fast as i can drag the tip. I would say that I burn up more tips pierceing than any other cutting method.

 

[ovrszd]

Yep, I do the "drill a hole" thing most of the time.

 

[CNC Dan]

Not sure I understand why non cutting time would be hard on a tip. I was told it's the starting, that's hard. And when you are not cutting, there is less heat coming back to the torch. How is the capacity of the device otherwise?

The worst mess I ever made of a tip was trying to make holes in a railroad rail! I guess it wasn't a gouging style tip.

Cutting: current goes from electrode to workpiece. Workpiece is heated and blown away.

Non-cutting: less current goes from electrode to nozzle. Nozzle heats and is eroded.

 

[Industrial Toys]

That makes sense, if you mean to say MORE current goes through tip when not cutting, creating heat, rather then current going to the work.

 

[CNC Dan]

That makes sense, if you mean to say MORE current goes through tip when not cutting, creating heat, rather then current going to the work.

Yes, that's the idea. But the nozzle(tip) still gets heated when cutting.

And when you are drag cutting, current goes from electrode, nozzle, work. Which also heats the nozzle.

So if possable, use non conductive templates, and keep the nozzle from draging on the work.

 

[Big Barn]

I'm not new to plasma cutting, but I've gained great insight from this thread.
Thank, everyone!

Terry