Construct a variable radius round

Choose Home tab→Solids group→Blend .
On the Blend command bar, choose Variable Radius.
Select the edges you want to round.

Note:

The selected edges must form a single chain, and they must be tangentially connected at their end points. QY CAD calculates a smooth transition along the length of the chain.
Use the Blend command bar boxes to define characteristics of the rounds.
Define the end you want to apply the start radius to.

Note:

By default, you can select endpoints and midpoints. If you need keypoints in other locations, add them using the Intersection Point command.
In the Radius box of the Select Vertices step, type in a radius value, and click the Accept button on the command bar.
Define the end to which you want to apply the end radius.
In the Radius box of the Select Vertices step, type in a radius value, and click the Accept button on the command bar.
On the Blend command bar, click the Finish button.