Plasma cutting

[Dave M]

This is just a tip I am not sure if this is the right section but it was sure a problem. I have a hypertherm powermax 1000 and last night I needed to cut out some parts for the blower connector and hole for my fire pot for my new coal forge and blower. The cuts looked like garbage very jagged and slagy. I make much cleaner oxy cuts so I was miffed. I checked my air pressure my filters and grounds nothing helped. Then I checked my tip and cup they were wasted. I remembered the last job I used this on was a bridge job in which I had to use bottled nitrogen. Nitrogen burns up you consumables much faster and make real ugly cuts. After replacing consumables it made my cuts look like they were done with a bandsaw.

[Dodge]

Good to know Dave. I knew about tip quality vs cut quality but not the nitrogen part. Thanks!

[tompdw]

I've never used nitrogen. Mine is connected to my air compressor. Thermal Dynamics cutmaster 81.

[Dodge]

I've never used nitrogen either, but I understand its the way to go for portability. Anyone care to expound on this?

[GrandLordKhorne]

Nitrogen is required under certain codes because it reduces the chances of contamination in structural welds. It’s something that some moron engineer wrote into a couple of code books without ever trying it himself. Based on what I know and have been told it is the equivalent of putting on white gloves to make sure your pictures don’t get dirty when handling them (Ya, it keeps it cleaner but not by much). And as I understand it, the reduction in contamination has more to do with water vapor in compressed air than the actual gas composition. They pull the same BS with air/carbon arc gouging now and then. But yes, it eats your consumables because pure nitrogen is not as effective at cooling them as air is and makes for a hotter cut from what I understand.

Having said that, some of the guys I know who do it for a living have gotten good enough with nitrogen in there plasma that it looks just like air cut. I have also seen one person do plasma cutting with pure oxygen for a special application (don’t try it at home, from what I understand there are special safety considerations) and that made the most incredible cut I have ever seen in my life.

[Ten Hammers]

I have used nitrogen at the suppliers only. Clean compressor tank, trap and hose make big difference. Keep stuff drained. Most times cuts are ground before any welding ( same as gouged ) anyway and engineers can be yes idiots ( especially drawing prints ). My first ( 350 ) lasted 9 years and current ( 600 ) both Hypertherm. Was told that motherboard was bad on old one but wish I had it back for sheet. Don't get me wrong, the 600 is great but the consumables for the smaller torch were about 1/2 price comparitively. The 600 has given me power of course. One trade for another.

[Dave M]

I had to use the nitrogen because the compressed air the supplier first gave me was filthy and damp and working building this bridge in the middle of no where had big limitations. Medical grade air or breathable air works great but cost huge coin. Nitrogen is clean, dry and the price is not too bad, but it does not cut as clean as regular compressed, dry clean air. In my shop I run double filters and an air dryer on my cutter.