All of these rapier hilts have a lot of curves in their designs, and when first approaching SketchUp, it’s not immediately obvious how to create a curved object. So here are some of the things that helped me out.
Again, some extensions were very useful to me. There are three that I can think of:
This tool allows you to make more natural and intricate curves, more easily than with what is provided with SketchUp, which is just basic arcs. While I didn’t use it for the Cup hilt, it was invaluable in creating the Swept and Pappenheimer hilts.
This tool adds a number of default three dimensional shapes that can be created. Out of these I found the “Dome” to be the most useful, to cap off round “holes”.
This tool allows you to take any group you’ve made and bend it to an existing curve. I used it to create the hand guard on the Swept hilt.
First of all, look at the shape you are trying to recreate, and try to divide it into a few curves that you can recreate with the Bezier Curve tool. When creating a Bezier Curve with the extension, you select two points that you are trying to connect, and then you get to select the angle and intensity that each end rests at. Guide points are extremely valuable for making it clear where you want these points to meet.
It might not be likely that you can create your desired curve with just one bezier curve. Luckily, the tool snaps to the three axes, and if it is attached to an end point, it can snap to the tangent of that point, creating what appears to be a single, smooth curve.
Of course, this is just a line. We’d like to take this into the third dimension, since our purpose is 3D printing. Create a circle perpendicular to one of the end points. Then double click your curve, select Tools -> Follow Me, and click on your circle.
You might need to reverse the faces to make sure they are white on the outside, indicating that it is solid, but now you have a three dimensional curve.
This curve has a pretty harsh ending, so let’s put a dome on the end of it. Using the guide tool, measure the radius of the circle, in my case it was 0.174046″. After you’ve installed the Shapes extension, go to Draw -> Shapes -> Dome and set Radius to your measured value. I’ve found setting Segments to 6 usually matches up with the default circles. The dome is created about the origin, and you can move it to one of the end points using the move tool. Then, view it on the side and rotate it 90 degrees to cap off the curve. Afterwards you can delete the internal face to get a solid again.