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View Full Version : Cold Air Guns for improved cutting



Roger Lueck
09-03-2013, 3:45 PM
Has anyone attempted to use a Cold Air Gun, such as those from Exair, as an air assist to improve cutting performance in wood and/or acrylic?

Dan Hintz
09-03-2013, 5:00 PM
Has anyone attempted to use a Cold Air Gun, such as those from Exair, as an air assist to improve cutting performance in wood and/or acrylic?

It would defeat the purpose of the laser in many respects. The intent is to locally melt/vaporize the acrylic and blow it out of the crevice... if you cool the material before it's fully ejected, you end up with massive dross attached to the cut. Not to mention the cut itself will likely be highly striated.

With wood, I see no benefit, but I don't see a downside, either.

Mike Null
09-03-2013, 5:25 PM
I share Dan's opinion though I feel that air assist alone even slows cutting and engraving to the point that extra power must be used. This is particularly noticeable on wood.

Dave Sheldrake
09-03-2013, 6:17 PM
+3, I can't see any benefit either for wood, not at the pressure levels and power that light industrial / hobby lasers run at. On a lab bench maybe, but real world? there's nothing that would technically suggest any benefits. Likewise I see no drawbacks other than the cost of an item that achieves little or nothing.(maybe at low pressure it would require more "heat" to be induced in the materials requiring more power if anything)
For acrylic it would almost certainly be counter productive for the reasons Dan gave.

cheers

Dave

Rodne Gold
09-03-2013, 9:00 PM
They work well with CnC's that use cutting tools where heat is the enemy.

Greg Bednar
09-03-2013, 10:12 PM
They also get so cold water condenses on it and drips onto the surface of the work. Not good for some materials.

Roger Lueck
09-05-2013, 10:47 AM
Thank you for your input, I'll continue to use a stream of air directed to the cut area.

Mike Lysov
09-05-2013, 5:51 PM
The biggest advantage of air assist apart from adding protection for a lens and a mirror is that if you do it with high pressure there is no chance for residue to stick at the front of the material. It should help to cut faster too because thin air stream supplied directly to cutting area removes debris from a beam path.
The first time I changed my air pressure from 10-15 PSI to 30 PSI and added a long nozzle I could start cutting with 2.1% of speed instead of 1.9% for 6mm thick MDF. So it does really help if you do it right. It has nothing to do with air temperature though.