Creating Radius Between Circle and Rectange

I’m trying to create a drawing for an insert into an LED base, the drawing is simple enough but there is one thing that I can’t find an answer to.

I created a circle and a rectangle then used Boolean Union to merge them together, I put a 5mm radius on the bottom corners of the rectangle but can’t figure out how to put a radius where the circle meets the rectangle.
This is the overall drawing:

The radius I want is where the little circle is that’s currently forming the radius in the right place:

Any help would be appreciated, I’m finding Lightburn quite intuitive after using AutoCAD before and I get that it isn’t a full on drawing package but I am hoping there’s a way to do this.


Node-edit the lines and use (T)rim/(D)elete to remove the “corner” of the rectangle and just let it flow into the circle?

Because one line is part of a radius, it cannot be done in LightBurn with the “normal” radius tool.

Rojhan, I broke it all up and used the node edit function - job’s a good one:

I didn’t use the trim but just moved the ends to match then made sure it all worked right, they may not be identical but they will do, I’ll remember to draw half the line first then mirror it in future.


The corner radius tool will do this IF the two lines are actually lines, not curves, and are long enough to accommodate the chosen radius. We’ll be extending the feature to handle more complex options, like curves meeting, but the math is dramatically harder.