Do you own a CO2 laser table? Whether you are a novice user or a seasoned operator, this guide is packed with practical advice and professional tips for optimizing your engraving and cutting projects, as well as how to maintain your machine for long-term performance. Here is everything you need to become a laser engraving and cutting pro.
Recommendations for Use
Display X and Y Coordinates on the Work Surface
By moving the machine's engraving head using the keyboard's directional arrows, the precise coordinates of the engraving head are displayed on the machine screen. This display can be combined with the use of the red pointer beam, making it very easy to find precise physical coordinates and transfer them to the software to perform an origin offset. This is particularly useful when working with irregularly shaped scrap material or as an alternative to the Point and Shoot function.
Shifting the Engraving Origin
The engraving origin can be shifted directly from the machine controls. Simply move the bridge with the directional arrows and confirm the position as the new origin with the check button. This is a handy feature for engraving at a precise point on a part, or for adding text to be engraved quickly after cutting.
Validate the Distance Between Object and Laser
When inserting a cutting table or a large object into the machine, you must lower the table by pressing the Z button while using the down arrow, then confirm the new position of the work surface using the check button. If this action is not taken when engraving or cutting is launched, the table may rise to its initial position, which could crush the engraving head on the object or cutting table. This is a critical step that should never be skipped.
Fume Extractor Management
Typically, the fume extractor is controlled by the laser machine and only activates when it is running -- so you do not need to worry about switching it on and off manually. However, when cutting material, it is possible to extend the extractor's runtime by a few seconds in the Gravostyle software to ensure that the last of the smoke generated by cutting is fully sucked out.
Engraving and Cutting Your Creations
Importing Files into Gravostyle
To accurately import your engraving or cutting requirements into Gravostyle software, it is important to choose the right file format:
- Vector formats (AI, EPS, PDF, SVG, CDR, DXF): Blue lines for shapes and contours allow you to engrave shape outlines. Black lines for solids allow you to engrave a filled shape.
- Raster formats (JPG, JPEG, PNG, PSD, TIFF, GIF, BMP): Allow you to burn a monochrome gradient image and manage grayscale files.
Settings for Engraving with Gravostyle
In general, for standard engraving, power is reduced and speed is high. This ensures fine, precise engraving without marking or burning the material. For deep engraving, power should be increased and speed decreased to dig deeper into the material while avoiding burning or deforming it. You can also assign different engraving parameters to different elements of your design by assigning different colours to them, then specifying the laser parameters for each colour when sending the file to the laser table. This saves time and ensures more precise engraving results. All Windows fonts are available in Gravostyle, and you can install additional fonts if you wish.
Photo and Illustration Engraving
With Gravostyle, it is possible to reproduce a scanned drawing, logo, or photo taken from a phone. The laser table can retranscribe the grayscale of the design when engraving -- meaning you can engrave a logo in several shades, or a black-and-white image with shades of grey. To ensure good marking quality, always use a high-quality photo (300 dpi minimum). The quality of the engraving can never be higher than that of the source image. If image quality is insufficient, the result will be blurred or pixelated. The higher the resolution, the longer the engraving will take -- it is up to you to find the right balance between quality and time.
Cutting Out Your Creations
For cutting, use vector format files with orange lines in the Gravostyle layout to cut shapes by following their contour. In general, when cutting, power is high and speed is low to cut through the material. The thicker the material, the higher the power needed and the lower the speed. All engraving and cutting modes can be combined in a single engraving file -- simply assign different colours and specify the corresponding laser parameters for each.
- When cutting, always reduce speed rather than increase power. For the same speed, it is better to use 80% power than 100%.
- Do not remove the protective film from Gravotech material when cutting.
- Use material calibration to find new parameters for unfamiliar materials.
Setting Up Materials on Gravostyle
Depending on the material, laser power and speed parameters must be properly adjusted to obtain quality engraving and cutting results. In Gravostyle, these parameters are expressed in percentages rather than Watts for simplicity.
Pre-Set Parameters for Gravotech Materials
All Gravotech materials parameters are pre-registered in Gravostyle. A library provides automatic settings per material, for both engraving and cutting. When a new Gravotech material is released, a Gravostyle update includes the new parameters automatically.
Non-Gravotech Materials
For materials that are not from the Gravotech range, there is a tool called material calibration. It allows you to perform several tests by gradually increasing speed or power, creating an engraving sample chart that will help you choose the right rendering. You can then save your settings in the software with a specific name. Settings can be saved as Factory presets (Gravotech database) or User presets (your own database for materials you use frequently).
Optimizing Laser Use by Material and Application
Engraving and Cutting on Wood
- Engrave typography in the direction of the wood grain (like lines on a sheet of paper).
- Defocus the laser slightly by 2 mm for a darker, shallower marking.
- When cutting, put masking paper on the surface of the wood to avoid smoke deposits and glue residues. Cutting edges will be preserved against dark marks.
- Wood can be made flexible with dashed cutting lines. The space between the cutting lines defines the maximum bending angle.
Engraving on Glass
Glass is a material that can overheat, causing microcracks. To prevent this, put wet paper on the glass and engrave through the wet paper. For cylindrical glass items (bottles and glasses), use a cylinder turner to rotate the glass during engraving for full 360-degree coverage.
Engraving and Cutting on Acrylic/PMMA
- To cut acrylic with a smooth edge, set speed fairly low and increase vector DPI.
- Defocus inside the material (focus point not on the surface, but at approximately 1/3 of the material thickness).
- Use a pin table for cutting to limit beam returns.
- For transparent acrylic, engrave on the reverse side and in mirror image.
Photo Engraving Tips
- On anodized aluminium or acrylic: use a uniform background, convert to negative. In Gravostyle, use the Grayscale engraving method -- white will not be engraved, black will.
- On wood: remove the background in Gravostyle. Use image format or PhotoLase engraving method.
Speed Optimization Tips
- Use the horizontal axis to optimize marking time -- position your design elements along the horizontal axis rather than vertically.
- Reduce DPI for faster engraving at lower resolutions when high detail is not required.
The Most Frequent Mistakes
Understanding these common pitfalls will help you optimize the use of your laser table and improve your engraving and cutting results:
- Wrong connection or cable: Check that all cables are correctly connected before you start engraving.
- Forgot to select the engraving to be sent: Always use the preview tool before you start engraving to avoid errors and loss of material.
- Incorrect positioning of engraving on object: Before you start, check the positioning of the engraving. Use the pre-engraving simulation, which uses a red dot to simulate the engraving position directly on the object.
- Using too much power: It is better to use too little power than too much. If the engraving is not pronounced enough, you can always make a second pass. But if the engraving is too pronounced or even burnt, it is impossible to go back.
Safety and Maintenance Recommendations
Using a Laser Table Safely
A CO2 laser table is a class 2 laser machine. No specific safety measures are required for the operator beyond following these guidelines:
- Operating the air assistance during cutting improves cutting quality and facilitates better smoke evacuation.
- For safety reasons, do not leave the machine unattended during engraving or cutting.
- Do not engrave or cut PVC, as the chlorine present in its composition is released as a gas and is harmful to the user and the mechanical parts of the laser table.
- For user safety, do not engrave with the door open.
Maintenance Operations
To ensure optimum operation of your laser table and prolong its life, follow these maintenance instructions:
- Clean the lens before working with the machine, to avoid the accumulation of dust deposits when not in use.
- Keep your machine clean between uses. Pick up chips and dust debris and keep the worktable clean.
- Clean the mirror once a month to maintain optimum laser beam quality.
- Change the extractor filter when the indicator lights up, to maintain optimum filtration and prevent dust build-up in the machine.
- The service life of a CO2 laser source is extended when it operates within a temperature range of 68 to 77 degrees Fahrenheit (20 to 25 degrees Celsius). Keep the machine within this range to guarantee its performance.
A service and maintenance contract increases the machine's lifespan and guarantees maximum uptime.
Conclusion
Mastering your Gravotech laser table is a matter of understanding the software, knowing the right settings for each material, and following proper safety and maintenance protocols. With the tips in this guide, you now have the keys to understand and optimize your CO2 laser engraving and cutting operations for consistent, high-quality results.