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greg lindsey
05-25-2010, 10:25 AM
Having just celebrated my 11th year of laser engraving and cutting business, I figured I should know quite a bit about this work. However I have seen many of you use the term "banding" I am also sure that I have experienced this, but this is a term I am not familiar with. So please someone explain.:confused:

AL Ursich
05-25-2010, 10:30 AM
Missing or lightly engraved lines thought the artwork. Missing or light laser burning... Usually caused by changing the size of a Photo Grav picture after it has been processed or a mechanical problem with the bearings or drive.

AL

Doug Griffith
05-25-2010, 10:30 AM
Banding is visible variation along an axis. "Stripes" or "lines" could also be used.

greg lindsey
05-25-2010, 10:47 AM
OK,thank you.:D

Scott Shepherd
05-25-2010, 10:48 AM
I had a discussion about banding with someone at the factory and I was told that banding is present on all CO2 lasers and it can be done away with, but currently the cost to do away with it isn't something people would pay for. They also told me that they have built it and it does work, it just isn't practical from a cost standpoint.

You'll see banding a lot on clear materials or reverse engraveable materials. It's not as noticeable on normal engraving plastics.

Doug Griffith
05-25-2010, 11:03 AM
I had a discussion about banding with someone at the factory and I was told that banding is present on all CO2 lasers and it can be done away with, but currently the cost to do away with it isn't something people would pay for. They also told me that they have built it and it does work, it just isn't practical from a cost standpoint.

You'll see banding a lot on clear materials or reverse engraveable materials. It's not as noticeable on normal engraving plastics.

That would probably be the laser equivalent of stochastic printing where a random pattern/density is used. Tough to achieve with a gantry system and fixed power setting.

Scott Shepherd
05-25-2010, 11:07 AM
I don't know what that is Doug, but it wasn't that :)

It was tube related. They did something to the tube which causes it not to band. I'd prefer not to say because I don't know if it's something they want posted on a public forum.

greg lindsey
05-25-2010, 11:09 AM
Would that be what I experience when engraving text in red romark material, never can get the red/pink out with one pass, damn that stuff is hard to get white, normally tales two to three passes to get it perfectly white.

Doug Griffith
05-25-2010, 11:25 AM
I don't know what that is Doug, but it wasn't that :)

It was tube related. They did something to the tube which causes it not to band. I'd prefer not to say because I don't know if it's something they want posted on a public forum.

The thing about banding is that it is a produced by any number of things. Almost always an error. It could be a malfunctioning gantry system, driver error, variation in power output from the tube, the halftone pattern produced by the graphics software, or something else. A "magic tube" might lessen one of those variables but it wouldn't be a cure.