Rolling Ball Fillet with changing radius

Hi, I was trying to create a rolling ball fillet between two pipes. The tricky bit is that one of the requirements was to keep various radius in different segments of the joint. I used CreateRollingBallFillet method from Rhino Common, but this allows you to have a fixed radius only. I had to create multiple sections, based on multiple fillets, and finally do a loft with those sections in order to get the desired result.

This works, however it’s quite inefficient. If I want to it to be precise, I need to take hundreds of sections, that means generating hundreds of rolling ball fillets… that obviously takes time to calculate. Is there any chance to get various radii on that method? Or is there any reasonable workaround? Could by any chance McNeal implement a variable radius fillet in RhinoCommon API?


I’ve added this to the RhinoCommon wishlist:
If it is possible to do through regular Rhino commands, there is a decent chance we should be able to expose it in our APIs.

Any update on this?

Have you thought of using rail distance instead of rolling ball?

Hello Martin!

Could you please upload your gh. file for this?

Best regards

Sorry I didn’t keep this file.

What’s the problem?

Hello, thanks for replying!

I’m trying to make what would eventually be a cnc-made wood furniture joint, looking like the picture in your post 2 years ago. I made it to this with Sweep2 through with the two curves and four section lines. I also want to make the section lines fillet/bend like on your picture. But as you can see, everythig ende up looking quite funny!

Please post your Grasshopper file with the relevant inputs internalised.

There you go :smile:
Furniture (10.8 KB)

You don’t need to build the blend from scratch. You can use the fillet component like this:

Furniture (16.5 KB)

Thank you, as simple as that! How about if you want a combination of 90 degrees and fillet in the joint? Like this:

If that is the goal, then the main challenge is getting the curves in the right direction befor blending.

Furniture (29.1 KB)