MOPA Fiber Laser
The MOPA/Fiber 60W Galvo-head laser does super fast engraving and marking of metals, plastics, stone, tile and other inorganic materials. It can do 3D "deep" engraving on metals for things like coins and jewelry, and can engrave and do black or white marking on many materials. It also has the ability to do color marking on stainless steel.
"Default Focus Position" for the default 112mm lens is -328. This is the proper offset for the head to reach the surface of the XYZ table in the laser enclosure.
The thickness of the item you are marking (in millimeters) should go into the "Z" parameter or in fixture offset.
When marking - the (lowest) calibration line should be exactly 234mm from your work surface. (If not, one of these is wrong)
See diagram above. But remember:
Set the "Z" of an object to it's thickness in millimeters
Anytime you change a "Z", the head will have to move
Anytime you add a new object - remember to add/specify it's "Z"!
If you are working with objects that have the same Z distance you can set the fixture offset to the thickness of your item. This offset will then apply to all objects that are in the workspace.
Note if you have a scrap piece under your item the thickness of this must be added to the fixture offset.
Pulse Width: Standard Fiber laser uses a Pulse Width of between 100ns - 150ns. You might consider this a "starting point" for most settings. Rarely go much higher. Go lower for finer control and to eliminate flaring, burning, cracking, etc.
Frequency: Materials generally use settings around 20-50 kHz for general abrasion and marking. Higher frequencies generally result in less ablation and more heat. Higher settings generally used for frosting affects, and finer control in things like stainless steel colors.
Speed: Speed can be very high, especially when doing detailed hatching.
Power: Power is power...
Loop Count: How many times to repeat this pass
IMPORTANT: If you're unable to modify a parameter - you probably need to change the "Use Default Parameter" (first parameter) to "False" to allow you to modify.
Hit the "Parameter Library" button to get ready-made settings.
Settings that start with "F" were imported from a fiber laser and may not have it's Pulse Width set. (The Default Pulse width of "2ns" is usually not enough to mark anything!)
Settings that start with "BKG" were more recent ones tested/added by Brad. Probably will work - but might not be optimal.
Parameter settings are usually only half the equation. A refined process requires proper hatch settings as well.
If you're adding entries - prefix with something distinct from "F" or "BKG" (i.e. your name, or "USER")
Most important hatch settings are:
Mark Contour: Enabling will draw a contour line around the object - i.e. will trace the perimeter. A quick operation.
Enable: This enables hatching on an object. (i.e. filling the entire object)
Hatch Style: (The graphical picture) What type of hatch fill to be used. i.e. Unidirectional, Bidirectional, inner countour ring fill, etc. (See diagram)
Line Spacing: The space between contour lines. Generally around 0.01 to 0.001. This has a HUGE affect on hatch times!
Angle: Vertical lines, horizontal, diagonal, etc.
Autorotate Angle: Change the rotation angle by this mean degrees every time. Can help eliminate hatch lines
Remember - You can have multiple hatches ("Hatch1", "Hatch2", etc) defined for a hatch setting - each has hit's own parameters
Object can be modified after creation - by clicking them in the "Object List" in the upper-left then changing their settings in the lower-left. This includes settings of the object itself (such as size), text, and even hatch settings. Remember to click "Apply" after making any changes for them to take effect!
See video for quick into on using rotary tool.
See Cheat sheet below for quick reference.