SYNRAD, INC. - http://www.synrad.com  
Thursday, June 5, 2003
Issue 64

SYNRAD's sealed CO₂ lasers are used in a variety of industrial processes including cutting, welding, drilling, and marking. This news brief showcases some of the interesting materials and products that are processed daily by Synrad's line of CO₂ lasers and marking heads.

Trepanning Holes in Ceramic

     When drilling hole diameters significantly larger than the focused spot size, a method known as trepanning is used. Trepanning involves moving the laser beam in a circular path to effectively cut out the hole. Depending upon the size of the hole required, beam movement can be achieved using rotating optics, or more commonly, by simply moving the material or the laser beam while cutting.

     The hole shown in the photo to the left was made at a speed of 10 inches per minute (IPM) using 25W of power, due to the limitations of the particular X-Y stage used for applications testing. While trepanning, the laser was pulsed at 60 Hz with a pulse length of 4.9 milliseconds (ms). Straight-line cuts on the same material were achieved using 50W of power at a speed of 40 IPM, as the laser was pulsed at 240 Hz with a pulse length of 1.24 ms. Cut edges exhibited only a small amount of dross.

     The beam was delivered by an X-Y stage using a 2.5" positive meniscus lens that provided a 0.004" diameter spot with a 0.07" depth of focus. 40 PSI nitrogen was used as the assist gas. It should be noted that identical parameters (speed, power, etc.) were set when performing cuts on a 0.010"- thick sheet of ceramic.

Marking Leather

     Leather is another material that responds well to the CO2 wavelength during laser processing operations including cutting or marking. To illustrate mark quality, this baseball glove was personalized using only 10W of power at a marking velocity of 75 inches per second (IPS). The contrasting mark, "Lefty", was created using a filled Windows^® TrueType^® font (Commercial Script BT), 0.75" high, at a resolution of 325 DPI in a cycle time of 7.5 seconds. Beam delivery through the FH Series Marking Head was provided by a 200 mm focusing lens. Spot size was 290 microns (0.011") with a 0.098" depth of focus.

Importing Vector Graphics into WinMark Pro

      During importation, elements in a graphic file are sorted into individual entities such as lines, arcs, circle, and text objects. If the file contains only polyline objects, they are optimized and placed into a "Polyline SetX". If the import file contains other objects in addition to polylines, such as true circular objects, the graphic imports as a "GroupX" where non-polyline objects are independent of the polyline set as shown in Figure 1.

     You can choose to edit the mark properties of individual polylines while they are exploded so that different objects mark at different speeds, powers, etc.; however, if these objects are unexploded into a new, optimized polyline set then all polylines in the set are marked with the same properties as the first selected polyline in the set. Where different mark properties are desirable, you can instead choose to group similar polylines into their own specific polyline sets.

     As always, the latest released version of WinMark Pro is available from the WinMark Pro website at www.winmark.com. On the WinMark site you can also find Release Notes, our Laser Marking FAQ, demo .mkh files, and much more.

Browse Synrad's Applications Database

Search our online library for more applications of Synrad's sealed CO₂ laser technology. Sort by material, process, or industry.

http://www.synrad.com/search_apps/Default.htm

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