Can anyone help me? I can’t figure out how to make this curve in a way that looks good. It’s the highlighted part. I use the “Bezier Tool” tool.
Bezier curve.skp (132.2 KB)
Bezier curve.skp (132.2 KB)
For that, I’d just use the two point arc tool two times. You could fuss a bit more with the bulges if you want an even tighter fit to the image.
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While I agree with @slbaumgartner that this shape is easily done with two arcs your actual question is about Beziers and people reading the thread title will be looking for that.
So this is one way of drawing a bezier with the classic bezier from Fredo’s BZ Toolbar. With practice you can do it in a couple of clicks but I have shown here how you can add control points to easily adjust the curve.
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Thank you!
It may be more pedantic than most people care about, but Roman ogees use circular arcs and Greek ones use elliptical arcs. Those are both quadratics, whereas Bezier splines are cubic.
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If you want to slip into pedantry, when drawing your arcs you should be using the teal tangent to get a smooth transition. 
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I’ve never heard these words before, but this is very interesting. Can you please explain this like I’m five?
Might be that TIG’s Cyma Curve Tool from Sketchucation would be a good option.
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It’s here: https://sketchucation.com/pluginstore?pln=CymaCurve
It works with <v8 up to v24+
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In a basic sense you have curves that are parts of a circle, circular arcs, or curves that are parts of an ellipse. They may look similar but they are ever so different geometrically.
But a Bezier spline/curve is a rather complex mathematical construct that creates a smooth curve from point to point and, I may well be way off the mark with this, something that is more of the computer age than a general geometric term.
I believe beziers have been ‘understood and talked about’ for many centuries by mathematicians, and quite specifically in the early 20th but didn’t come to prominence until the 50/60 when computer algorithms got involved.
Just to show the difference between a curve made from a 1/4 circle and that made from a 1/4 ellipse.
I will point out here I am an uneducated man who only knows things due to life experience and as such can be easily, and happily, corrected by those with tertiary education.
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Bézier curves get their name from a French auto designer who innovated using them to get pleasant shapes on cars. The general idea of blending smooth curves together had been used since ancient times, but he spearheaded the use of cubic curves (that is equations involving third power exponents, as contrasted to quadratics, which are second power) and computer algorithms to generate them in the1960’s.
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As another note, cubic curves correspond better to what you get by bending a thin piece of material, which is why they are often called “splines”.
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If you want to use elliptical arcs, you need to start with circles that are scaled along one axis to transform them in ellipses.
Why not simply draw the figure with circular arcs and then scale the result.
See this SU file.
Elliptical curves.skp (210.0 KB)
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Is a great video by a very intelligent woman delving deeply into som aspects of beziers. I found it quite informative.
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This is amazing! Thank you for sharing it!