Uploaded March 2022 | Updated September 2026, 1 week ago
Demonstration trumps any theoretical argument.
I have long been fascinated by the supposed "magic" of RF laser technology. The prohibitive cost of those masterpieces of engineering can only be justified by industry or a small business. About a year ago I decided to build my own budget version by modifying a cheap Chinese glass tube machine with a 30 watt RF laser source. It did not take long to find that there was no "magic" to this complex technology after all. I tested and experimented for a few months before consigning the machine to a corner of the workshop where it remained unused for almost a year. With just 30 watts it was very poor at cutting and although the machine was capable of engraving at 1500mm/s, the 30 watt power limit meant that 500mm/s was the real ceiling. In the meantime, research with lenses and my glass tube machines allowed me to discover the importance of light INTENSITY for cutting. Purists will claim light is something you see and energy density is a more correct term....sorry, not for me.
I gravitated back to the RF laser source when I realized it possessed an incredibly high INTENSITY small diameter beam. However an RF laser beam diverges at about 7mm/m and as the beam diameter grows its intensity decreases. To make the beam diameter uniform across the whole work area and optical device called a beam expander does exactly what it says . It takes the diverging small high intensity beam, and increases it to a larger diameter that can be optically tuned to virtually parallel. Sadly, this increase (as mentioned previously) is at the expense of light INTENSITY. Less intensity is still fine for engraving but crucifies cutting potential.
Once that INTENSITY has gone it cannot be recovered. Putting the remaining intensity through a lens will amplify it BUT you cannot amplify what's not there.
Thus any RF source with a beam expander (and that means all those expensive machines!!) will be very inefficient at CUTTING. The fix is easy.......... throw more watts at the problem ( if you have LOTS more $)
Demonstration trumps any theoretical argument.
I have long been fascinated by the supposed "magic" of RF laser technology. The prohibitive cost of those masterpieces of engineering can only be justified by industry or a small business. About a year ago I decided to build my own budget version by modifying a cheap Chinese glass tube machine with a 30 watt RF laser source. It did not take long to find that there was no "magic" to this complex technology after all. I tested and experimented for a few months before consigning the machine to a corner of the workshop where it remained unused for almost a year. With just 30 watts it was very poor at cutting and although the machine was capable of engraving at 1500mm/s, the 30 watt power limit meant that 500mm/s was the real ceiling. In the meantime, research with lenses and my glass tube machines allowed me to discover the importance of light INTENSITY for cutting. Purists will claim light is something you see and energy density is a more correct term....sorry, not for me.
I gravitated back to the RF laser source when I realized it possessed an incredibly high INTENSITY small diameter beam. However an RF laser beam diverges at about 7mm/m and as the beam diameter grows its intensity decreases. To make the beam diameter uniform across the whole work area and optical device called a beam expander does exactly what it says . It takes the diverging small high intensity beam, and increases it to a larger diameter that can be optically tuned to virtually parallel. Sadly, this increase (as mentioned previously) is at the expense of light INTENSITY. Less intensity is still fine for engraving but crucifies cutting potential.
Once that INTENSITY has gone it cannot be recovered. Putting the remaining intensity through a lens will amplify it BUT you cannot amplify what's not there.
Thus any RF source with a beam expander (and that means all those expensive machines!!) will be very inefficient at CUTTING. The fix is easy.......... throw more watts at the problem ( if you have LOTS more $)
