Engraving a number on a flat piece of metal is fairly straight forward, but when you add a curve to that piece of metal, the engraving process can get trickier. Projecting a 2D image at a 3D object results in distortion as the flat image stretches or shrinks around the object’s curves.
Engraved text on flat plane. Image: Kurtis Garbutt, M&S
Imagine you’re projecting a word at a beach ball. Unless you’re using a special projector lens, the letter at the point closest to the projector is the one with the least distortion, and the letters look more and more odd as they stretch around the ball.
For the same reason, if you’re adding text or a logo on a curved 3D solid, you need to make adjustments to the image to account for the object’s shape. To do that, you’ll use the offset tool with its Expand option.
To engrave text into a curved solid surface with PTC Creo Parametric, follow these steps:
- Select the surface that you want to engrave, and then make a copy of the surface. Just press Ctrl+C and Ctrl+V. (Note. This creates a new surface feature that you’ll offset in the steps below.)
Not all solids are flat, however. This tip shows how to engrave text into a curve.
- Create a sketch on the front datum plane and add your text to the sketch. To do that, in the Model tab, click Sketch. Then in the 2D view, in the Sketch tab, click Text. Draw a line by dragging the cursor on the plane. When the Text dialog appears, type your text.
Sketching PTC on the front datum plane.
- Make an offset datum plane. To do that, in the Model tab, click Plane. When the new datum plane appears, drag it away from the part. You’ll use this plane to project the text back onto the solid in the steps below.
Creating a new plane
- Create a second sketch on the new offset datum plane. To do that, in the Model tab, click Sketch just as before. Then, in the Sketch tab, click Project. Click the initial sketched text and ensure you select entire loops, without overlaps. This projects the earlier sketch onto the offset plane.
Creating a second sketch on a new offset datum plane.
- For the new surface copy you created in Step 1, in the Modeling tab, in the Editing group, click Offset. Now expand the feature by clicking the Expand Feature option from the drop-down ribbon on the far left of the Offset menu bar. Click the text you projected to the second sketch, and you should see it expand to the solid surface copy.
Using Expand Feature to expand text onto solid surface.
- To ensure the text conforms to the curved surface, on the Offset menu bar’s Options tab, change the Side surface normal to option to Surface.
Using the expand option to correct projected text to curved solid.
- On your sketch, drag the text so it recedes into the surface rather than being raised on the surface. At this point the text is still part of the surface, and not engraved, however.
- Finally, to engrave the curved solid, select the new offset feature in the Model tree. Then in the Model tab, in the Editing group, click Solidify. Now click the option to remove material, and then click the option to flip the direction of the material being removed.
Finished engraved solid surface.
You can see a demonstration of these steps in this video from PTC University Learning Exchange. You’ll also see how to make adjustments such as changing the scale, height, and alignment of the text.
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