Greyscale to Real Depth: 3D Relief Engraving with HagoLaser
Learn how our workshop turns greyscale images into detailed 3D relief engravings on sterling silver using HagoLaser. We cover the workflow, depth calibration, and smoothing artifacts.
Working with greyscale images to create 3D relief on a fiber laser can feel like guesswork, especially when you are losing precious metal to trial and error. This guide shares our workshop's practical workflow for converting depth maps into tangible relief using HagoLaser, focusing on the steps and checks we use daily.
Setting Up for Relief: The HagoLaser Workflow
Our workshop relies on a consistent color-based workflow to manage cutting and engraving. HagoLaser reads specific SVG colors, including a greyscale image within an engraving operation, to create 3D relief.
Our process starts in Inkscape, a free vector graphics program. We design the piece as an SVG, using flat colors to define operations. The three primary colors we use, which are also the defaults in HagoLaser, are:
- Black
#000000: For inner cuts, like holes or interior details. - Blue
#0000ff: For engraving, including 3D relief. - Purple
#8800ff: For outer cuts, releasing the finished piece from the sheet.
These are defaults, but you can assign any color to any operation in HagoLaser's Colors library. If your shop uses its own color code, you can keep it. Lines in unassigned colors are projected by the red aiming light but not marked, useful for jig alignment.
The drawing is the job. Save your design in Inkscape, then press Mark in HagoLaser; it re-reads the SVG instantly. No re-importing, no file dialogs. If you mark the previous design, you simply forgot to save in Inkscape. We keep one working file, ours is literally called 1.svg, and we design in real millimeters – what you draw at 20 mm wide is marked 20 mm wide.
Installing the HagoLaser Inkscape Palette
To ensure your colors map correctly to operations, you need to install the HagoLaser palette in Inkscape. Our installer does this automatically. After installation, in Inkscape, look for the small arrow button at the right-hand end of the color strip along the bottom of the window. Click it, and select HagoLaser from the list. The first three swatches will then be labeled for inner cut, engrave, and outer cut, ensuring you pick the correct operation. This avoids a common first-run confusion where users pick Inkscape's default blue, which is not what HagoLaser expects, leading to nothing being engraved.
Understanding Greyscale and Depth in Relief Engraving
3D relief work involves removing material in layers, with each greyscale value in your image corresponding to a specific depth. However, one of the first lessons we learned is that depth is not what you order.
Material removal per layer depends entirely on your laser recipe. On our machine, using sterling silver at 95 % power, 700 mm/s, 40 kHz, with a 0.03 mm Z-step, we measured about 18 µm removed per layer. So, a 1 mm requested depth yields around 0.6 mm. This calibration is specific; change material or recipe, and you must measure again on scrap.
To illustrate our measured depth on silver:
| Target Depth (mm) | Measured Depth (mm) | Removal Efficiency (%) | Workshop Recipe |
|---|---|---|---|
| 0.03 | 0.018 | 60 | Silver, 95% power, 700 mm/s, 40 kHz |
Layered relief often shows "terraces" on slopes, like a topographic map. Smaller Z-steps won't fix this indefinitely, as the laser stops working usefully beyond roughly one millimeter of defocus. Addressing terraces requires advanced techniques, covered next.
Fine-Tuning Relief: Detail, Smoothness, and Edge Control
Achieving good detail and a smooth finish in 3D relief involves several critical adjustments beyond just setting the layer depth.
Dithering for Detail and Blending
Hard thresholds in engraving delete features shallower than one layer step; on our machine, features under 0.05 mm disappeared. HagoLaser uses partial coverage (dithering) for layer masks, restoring sub-step detail and blending terraces by blurring the pattern. This costs roughly 2.7 times more segments, extending job time.
Edge Compensation for Crisp Features
Edge compensation is crucial. Eroding each layer mask by half a spot size creates crisp walls and sharp features, preventing a soft mound. For silver, we use 0.04-0.06 mm offset to maintain fine detail. Getting this right is key to maintaining the integrity of fine details in your relief.
The Smoothing Pass: Melting Steps Together
The most effective smoothing for terraces is a final pass at focus height that modulates energy by depth. Deep areas receive more laser pulses, shallow areas fewer, creating a continuous gradient that melts steps together. This is far more effective than tiny Z-steps. For deep engraving recipes, which also require layered passes, this is a similar concept. You can read more about those settings in Deep Engraving Silver for Enamel: Our Workshop Recipe.
There is a practical resolution ceiling. Finer Z-steps mean larger rasters. For small jewelry, 0.02 mm steps are realistic, but for larger pieces, a coarser step might be necessary to manage job size.
Safety First: Before You Press Mark
Any time you operate a fiber marking laser, safety is paramount. A Class 4 laser, like ours, produces an invisible 1064 nm beam and reflections that can cause instant, permanent eye damage. Always wear laser safety glasses rated for 1064 nm (with an OD suitable for your source power), and ensure everyone else in the room does too. Metal is highly reflective, so reflections can go anywhere. Never leave a running job unattended. Laser marking produces metal fumes and fine particulate; proper extraction with a good filter is essential health equipment, not an accessory. While software may offer interlocks, remember that physical enclosures and interlocks are the real safety layer, and software can be overridden. Always prioritize physical safety measures.
Getting Started with HagoLaser and Your Machine
HagoLaser is a free Windows desktop program for JCZ DLC2 fiber lasers, designed for our daily jewelry production. It's in beta, offered as-is, and the user carries the risk of industrial machinery operation.
The first-run wizard makes HagoLaser setup straightforward. It automatically finds your EzCad3 installation, importing your laser's focus height from Motors.ini, galvo correction (.cor), and parameter library (pens) from MarkParamlib.ini as material recipes. This uses your machine's actual calibration. HagoLaser never redistributes JCZ files; it reads what's on your machine. For more, see Inside EzCad3's PARAM folder: where your machine's real settings live.
USB Driver Installation
One of the friction points we aimed to remove was the USB driver installation. HagoLaser communicates directly with your JCZ board using the generic WinUSB driver. Since HagoLaser v3.63, the installer handles this automatically. Just leave the "Install the USB driver" box ticked during installation, accept the Windows permission prompt, and HagoLaser should see your board immediately. If you are already using LightBurn, which also uses the WinUSB driver, HagoLaser will work straight away without any extra steps.
If HagoLaser doesn't see the board (perhaps you unticked the box, or Windows reverted to the factory driver), simply press the "Connect" button in HagoLaser. A notice will appear with a button labeled "Install the driver now". One click, accept the Windows prompt, and you are done.
Important Note: While WinUSB is installed, EzCad3 will not be able to see or connect to your laser. If you need to switch back to EzCad3, HagoLaser provides a simple button for this: go to the «USB Driver» menu and select "Give the laser back to EzCad3". After clicking this, you will need to switch your laser machine off and on again. The same button can be used to switch back to HagoLaser when needed.
Practical Takeaways for Your First 3D Relief Job
Here is the order of operations we recommend for anyone starting with 3D relief engraving:
- Calibrate Depth First: Before chasing fine detail or smoothness, measure your actual material removal per layer on scrap. Understand that 1 mm ordered will not be 1 mm achieved. Adjust your Z-step or layer count based on your material and recipe.
- Start with Textures: If you are new to relief work, begin with engraving surface finishes like hammered, brushed, or stippled textures over a region. These are much more forgiving than photographic reliefs because the eye doesn't have a "correct" reference, so small inconsistencies often read as handmade character.
- Use Dithering and Edge Compensation: Ensure these are enabled in HagoLaser's settings. Dithering brings back lost detail and helps blend terraces, while edge compensation keeps your features crisp.
- Plan for the Smoothing Pass: Use the energy modulation smoothing pass as your primary tool for eliminating visible layer lines, rather than trying to use excessively tiny Z-steps.
- Work in Real Millimeters: Design your greyscale images and surrounding vector shapes in Inkscape at their actual intended size. What you draw at 20 mm wide is marked 20 mm wide.
- Back Up Your Machine Files: Always keep backups of your
Motors.ini,MarkParamlib.ini,.cor, andLaserPW.inifiles from your EzCad3PARAMfolder. These are your machine's core calibration.
By following these steps, you can move from a flat greyscale image to a precisely engraved 3D relief piece, avoiding the common pitfalls that can waste time and material.