Nitrogen in AirAssist

[Aaron Koehl]

In the thread (http://www.sawmillcreek.org/showthread.php?t=19129) on puzzle pieces, Rodne mentioned using nitrogen in his AirAssist, which allegedly cuts down on charring while cutting thick paper or mat board.

Has anyone else done this, and to what result? (If you have with/without pictures to post, that would be wonderful).

How would you do this with an Epilog Legend, and what are some sources for adding nitrogen into the air assist? (Is it all N, or a mix added from a secondary line?)

Thanks for any info!

[Bob Reda]

Don't know how it would work on a laser, but we use straight nitrogen to purge copper lines when we braze or silver solder.

[Michael McDuffie]

It should be as simple as a bottle of Nitrogen with a regulator connected to the air assist input.
Some things to keep in mind, the Legend bypasses the air nozzle when it’s idle so it will vent out your bottle any time the laser is on but not running a job. You can plug the exhaust port on the solenoid but if you use the originally supplied compressor, that might not be good for it. The pressure rating for the Legend is 30 or 35 PSI, IIRC, I wouldn't set the nitrogen regulator higher than that.
I’m not trying to scare you, but…
When you pick up the bottle, mounting bracket and regulator from your local welders supply house, have them explain how to use the valves and the importance of securely supporting the bottle. Be aware that most shops won’t put a bottle inside a passenger car. One of the large tanks contains something like 3 million pounds of force wanting out right now.
In the quantities used in a laser engraver, nitrogen is inert, non-flammable, non-reactive and non-toxic. In the quantities used to cool food products to 10F, it can build up in a mixer and cause an explosion when the mixer is started if there has been a leak.

Michael

[Aaron Koehl]

It should be as simple as a bottle of Nitrogen with a regulator connected to the air assist input.
Some things to keep in mind, the Legend bypasses the air nozzle when it’s idle so it will vent out your bottle any time the laser is on but not running a job. You can plug the exhaust port on the solenoid but if you use the originally supplied compressor, that might not be good for it. The pressure rating for the Legend is 30 or 35 PSI, IIRC, I wouldn't set the nitrogen regulator higher than that.
I’m not trying to scare you, but…
When you pick up the bottle, mounting bracket and regulator from your local welders supply house, have them explain how to use the valves and the importance of securely supporting the bottle. Be aware that most shops won’t put a bottle inside a passenger car. One of the large tanks contains something like 3 million pounds of force wanting out right now.
In the quantities used in a laser engraver, nitrogen is inert, non-flammable, non-reactive and non-toxic. In the quantities used to cool food products to 10F, it can build up in a mixer and cause an explosion when the mixer is started if there has been a leak.

Michael
Thanks for the info, that's along the lines of what I was thinking.

I would like to see how much the charring is reduced for 1/4 wood sheet if anyone has a picture-- ?