What's the Frequency Kenneth?

[Walt Langhans]

Sorry I couldn't resist :)

What the relationship between the frequency settings with regard to the power and speed setting? If I'm just trying to cut something as quickly as possible do I crank the frequency all the way up and then adjust down the power? Also do keeping the frequency cranked up shorten the tube life?And any other info you have regarding the subject will me most appreciated.

Thanks,
Walt

[Gary Gunderson]

Hi Walt --

I just asked someone at Trotec this exact question. According to Trotec, the higher the frequency for a given material, the slower it will cut. So, if you were cutting acrylic at 10,000 Hz, you would have to cut slower than you would at 2000 Hz. The trade-off is the quality of the cut. For most materials, the higher the Hz, the better the cut quality in the sense that you won't see as much "ridging", or the small lines along the cut edge from the laser pulses. However, when I went to test this after talking to them, I found no noticeable differences. I lowered the Hz on a cut I had been doing at 10,000 Hz, and wasn't able to go any faster by lowering the frequency down to 1000 or 2000 Hz. The only time I have noticed a difference, was that certain materials -- rubber and some fabrics -- tended to cut much better with less pulses. I'm sure someone a bit more knowledgeable on the technical side of things around here will be able to expand on this quite a bit.

[Walt Langhans]

That's odd I would have thought the higher the frequency the faster. I'm also kind of surprised with all views only the one answer, don't tell me I've stumped you guys ;) I guess it looks like I'll just have to mess with it.

[Jiten Patel]

Hi Walt,

I asked the same question some time back - http://www.sawmillcreek.org/showthread.php?148519-Relationship-between-Speed-and-Frequency!&highlight=

Hope it is helpful.

[Walt Langhans]

Ahhh I see, thanks! Yeah helped wrap my head around it :)

[Mark Sipes]

The Trotec software manual suggest that the raster frequecy (ppi) Pulses per Inch be larger or equal to the DPI. The vector (cutting ) frequecy is just that pules per inch.


PPI
Pulses per inch (laser pulses per inch).This setting determines the number of laser pulses per inch emitted by the laser.This occurs depending on the position, e.g. the pulses are always emitted at thesame interval irrespective the speed.Adjustment range: 100 - 1000 PPIThe higher the selected PPI value is, the better is the quality of theengraving. To obtain a good result, the PPI value should be usuallylarger than or at least the same as the dpi setting of the printer driver(Process options – Resolution), e.g. a minimum value of 500 PPIshould be selected for a resolution of 500 dpi. A low PPI value is onlyuseful when processing some types of rubber or in cases where thecontour is only to be perforated but not cut through. Unlike theresolution in dpi, increase in PPI does not have an effect on theengraving time.

Hz
Frequency of laser pulses during cutting. This setting determines the number oflaser pulses per second emitted by the laser. Unlike engraving, with cutting it is notnecessary to create fine contours by means of resolution. In this case, the positionsensitive control used with the PPI can therefore be replaced by a set frequency.Adjustment range: 1000 - 10000 Hz for CO2 systems,10000 – 150000 Hz for YAG systemsAdditionally YAG systems can use frequency mode for engraving.