I am in charge of the daily use of our Bystronic 3015 and seeking help with cutting aluminum. Our stock for the laser consists of .080" (2.5mm) , .125" (3mm), and .250" (6mm) 5052 alloy - 4'x10' and 5'x10'. Please refer to the lower part of this post for machine specs.

Currently, we are receiving a hard, "sawblade" burr on all cut edges of .125" and .250". The .080" leaves a smaller burr is the same density. Both burrs are hard enough to shred our strongest 80 grit that we use for debur. The plume is usually tilted slightly away from the the feed direction with white and yellow "sparks". We don't typically get a plasma burn on the top of the material, but it does still happen at points where an axis change will happen on top of a grate. In the past, .250" has always produced a worse result, but we have been succesful in reducing the burr to the same as what we get on .125". The .080" tends to cut clean, only leaving a finger-rocking burr if any.

We use Nitrogen for all of our aluminum work and Oxygen for steel. .250" aluminum requires Oxygen as an assist gas.

Tape shot reveals that we have an oval shaped or "cat's eye" beam path. Main operator claims that this causes a lot of our trouble. I have not found enough information to back up that claim.

Our ultimate goal is to minimize impact on our Spray Prep department with post-laser prep. I'm personally trying to set a tolerance of less than 1mm for acceptable burr.

Here are our parameters:

Head: 5"
Focal Point: 1mm
Nozzle Diameter: 1.5mm
Nozzle Type: HK15
Power: 4K, 70% piercing, 40% Cutting
Feed: 7500 mm/min
Gas Pressure: 3 bar piercing, 8 bar cutting

Head: 7.5"
Focal Point: 3.5"
Nozzle Diameter: 1.75"
Nozzle Type: Hk17
Power: 4k, 80% piercing, 75% cutting
Feed: 3150 mm/min
Gas Pressure: 2 bar piercing, 9 bar cutting