A lot of people struggling to engrave curved or uneven objects don't realize there's a feature built into xTool Studio that can fix it. Curved surface mode measures the shape of your item and adjusts the focus as it engraves, so you get much cleaner, more consistent results.
It works on the xTool F-series machines with a camera, including the F2, F2 Ultra and F1 Ultra. I tested it on one of the hardest shapes there is, a golf ball, using the F2 Ultra UV. Below is every step, a side by side with flat mode, and the settings I used.
Jump to: Set up and focus · Switch to curved material · Set the measuring area · Measurement density · Check the 3D map · Add your image and engrave · Flat vs curved
1. Hold it steady and focus on the top
A golf ball has an extreme curve and lots of dimples, so if anything is going to test this mode, it's this. Two things matter before you start:
- Placement. Hold the item steady and in the center of the work area. I used my self-centering jig.
- Focus. Focus exactly on the top surface of the item.
Then click New project in xTool Studio. It connects to your machine and takes a camera snapshot.
2. Switch to curved material mode
Normally you'd stay in flat surface mode and try to size the design small enough that the curve doesn't distort it. Instead:
- On the right, click the mode, which says Process on flat surface by default.
- Choose Curved material. There's a little video button on it if you want xTool's demo.
- The background camera picture is removed. If a prompt doesn't pop up automatically, click Curve-measure on the right.
3. Set the measuring area
The next screen asks you to set a box and frame it onto your item. The box must sit entirely on the item and not hang off the edge.
- Click Framing. By default the box is 50 x 50, which was far too big for a golf ball.
- Either drag the box on the diagram, or type the size in the W and H boxes. On my ball, 28 x 28 kept the box fully on the surface.
- Click Next.
4. Set the measurement density
This is the critical part. The laser probes lots of points on the surface, and each one tells it exactly how far away that part of the item is. It then knows how to adjust as it works across, so every point stays at its best focus height.
The default is 3 x 3 points, and you can go up to 20 x 20. The more points, the more detailed the map, and the less rippling and stepping you'll see in the engraving. I use 12 x 12 for golf balls and it's worked really well.
Set your rows and columns, then click Start measuring.
You can watch it probe each point on the item, and follow along on screen at the same time.
5. Check the 3D map
When it's done you get a 3D map of every point, and you can see it's mapped the golf ball really well. If a probe misses or lands off the surface, you'll get an error and won't reach this screen. Go back and make sure the box is fully on the item.
On the right there are two sliders:
- Smoothness gives a smoother finish. Dragging it up to 5 adds more points between the measured ones.
- Tension I also played with. The red zones are flagged as unsupported, a warning that they may not engrave well. Changing the tension moved them slightly, but it didn't do much in this case.
Click Done, and you get a square of usable space that represents your curved surface.
6. Add your image, settings and engrave
Import your image with the Import button. You can just size it to fit, or crop it with a Mask to fill more of the surface. I wanted to push it to the limit, so I set it to 28 mm, centered it, then made it as big as I could so it covered the ball. A high contrast portrait makes for a great test.
For the material, I picked White ABS Plastic because it's similar to the golf ball cover. Then I clicked Adjust and Auto Adjust to optimize the contrast and sharpness for a white surface. These are the image settings I used on the F2 Ultra UV:
| Setting | Value |
|---|---|
| Dot duration | 302 µs |
| Power | 83% |
| DPI | 375 |
| Frequency | 40 kHz |
| Bitmap mode | Jarvis |
Golf balls vary by brand, so run a test first.
Click Process. You can't frame it at this point because it's already been framed, and you won't get an estimated time either. Just start it and watch.
The result is brilliant. It's gone right around the curve, held focus the whole way, and there are no rippling artifacts.
Flat mode vs curved mode
To show the difference, I engraved the same grid on two of the same brand of ball, one in flat surface mode and one in curved mode with a 12 x 12 measurement grid.
The curved mode ball has consistent lines and color on every corner, even down the sides. The flat mode ball really struggles on the curved parts, and the color isn't consistent. On a photo or text, the difference would be even more obvious.
The one thing to remember
If you take one thing away, it's the measurement density. The default 3 x 3 grid can leave a visible stepping ripple. Increase it to 12 x 12 or more and those artifacts drop right down. Get that right, along with good positioning and an accurate measuring area, and it opens up a lot more curved items you can engrave.
For more tested settings, see my free Laser Settings Library and the xTool F2 Ultra UV settings page. The self-centering jigs I use are in the F1 Ultra and F2 Ultra jigs. If your item has an awkward outline rather than a curved surface, have a look at how to engrave patterns on irregular shapes.
What curved items are you engraving? Let me know in the comments on the video.
