Centered rectangle with fixed radius corners?

[feklee]

How do I create a rounded rectangle with the following constraints?

• Fixed corner radius: 3 mm
• Center of the rectangle: origin

Later I want to be able to resize the rectangle entering precise numbers. The corner radius should not change, and it should remain centered.

[jeff_strater · Accepted solution]

hi @feklee,

Yes, you can do this.  It's a little tedious, unfortunately, due to a bug in Fusion where the sketch fillet will delete the coincident constraint to the construction lines, so you have to go back and re-apply those.  But, the rest is pretty straightforward:

Jeff

[feklee]

Just replicated what you did, and it works flawlessly. Thanks!

Still I'm not sure if I understand what the Coincident constraint does.

[HughesTooling]

Here's another way that's quite quick. But the best advice is leave the corners sharp in the sketch and fillet the 3d feature after extruding.

Mark

[jeff_strater]

I like @HughesTooling's method.  Quite slick

Regarding Coincident, it can be used for a couple of things:  Making two points stick together, or constraining a point to be on the infinite extension of a curve (line, arc, spline, etc).

Here's a quick video show how this works with a point and a line:

Jeff

[feklee]

Thanks for the video about the Coincident constraints, very instructive!

[feklee]

@HughesTooling Thanks, that looks like a nice solution! What took me a while to figure out is that one needs to hold shift when selecting the side of the rectangle with the Horizontal/Vertical constraint selected. I wonder where that is documented.

[HughesTooling]

Shift to select midpoints was implemented a while ago. You used to be able to pick midpoints without the shift key but it got in the way all the time, you'd be trying to add an angle dimension between 2 lines but end up picking a midpoint and get a distance instead. It was announced in a What's New but don't know where you'd find it in the help.

Mark