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View Full Version : What should I know about Frequency?



David Fairfield
12-14-2011, 10:49 PM
After 5+ years of day-to-day business & hobby lasering, I'm here to tell you I still don't really know anything about frequency. :o I follow the settings in the manual, but otherwise I pretty much ignore it.

So, what's a simple way to understand Frequency? And more importantly, what can Frequency do for me? :)

Thanks!
Dave

Rodne Gold
12-15-2011, 12:50 AM
Its all about "drilling" , the way the laser cuts or makes marks is either by drilling lots of overlapping holes or firing overlapping pulses. look for "PPI" or Pulses per inch on the boards , lot's been written about it.

David Fairfield
12-15-2011, 8:54 AM
I know its about shooting little holes, the edge of the material can get little sawteeth when I'm at a lower frequency. What is the advantage of that?

At lower frequency is the laser applying more power per hole? Or is it applying the same power per hole, and thus basically applying less power overall?

Why is frequency not a factor in raster engraving?

Dave

Michael Hunter
12-15-2011, 9:49 AM
I do find that on my machine I get more power per pulse at lower frequencies. The effect has got more noticeable now the tube is ageing.

For acrylic and many plastics, you want the power as continuous as possible, so that means choosing the highest frequency available on the machine.
For wood and similar materials prone to charring, low frequency usually works best as the pulse drives right through the material and then stops so there is little "spare" energy to start the material burning/charring.

When rastering, the "frequency" is set by the dpi/ppi that you have chosen - one laser pulse for each dot.
Try engraving at 75dpi and you will see.

Martin Boekers
12-15-2011, 12:01 PM
You may try testing it. Cut a circle and a square at 500 htz the do the same cut abut add 500 htz to it each time.
See how it reacts to each substrate. You may find you can cut nicely with a faster speed than you are using.

David Fairfield
12-15-2011, 12:46 PM
Cool idea, thanks Martin. Michael thanks for the tips. Has anyone else come up with other simple "rules of thumb" to keep in mind regarding frequency (or frequency vs types of materials)? I guess that's what I'm asking for, and it sure would be useful.

Dave