Creating tubes in Rhino Mac

I seem to be having trouble with the interface for creating tubes.

I want to create a tube with an OD of 6.1 mm, and a wall thickness of .6 mm.

So I go to Solid/Tube and choose the base for the tube. I check Solid. I then type 6.1 which gives me the required OD. The next screen shows “Diameter” and “Wall Thickness”. I don’t get the point of this screen. “Diameter” in this case seems to be the Inside Diameter of the tube. However, if you enter an ID for a tube, you don’t need to specify a wall thickness, and if you enter a wall thickness, you should not need to specify an ID.

My preferred way of working is to enter only the wall thickness. However when I do that, I end up with a tube of which the ID is in fact the wall thickness I entered, and the wall thickness is therefore much thicker. It is wrong every time. So to do it correctly, I now have to calculate the ID for the tube I want to create, and enter that. the Wall Thickness field is left blank.

What am I doing wrong? How do I create a tube by specifying the OD and the wall thickness, and NOT the ID?

I raised the same issue a while ago: Tube around curve - wall thickness error
However, I also noticed it has not been resolved yet.


I don’t use this command much, but just trying it now. I believe the 2nd screen is so you can enter “either” a diameter or wall thickness.
I used wall thickness after entering a radius of 3.05 (6.1mm diameter). I then used a wall thickness of -0.6mm and it then gave me the option for length of tube. I used -0.6 so the thickness was on the interior of the original 6.i0mm dimension.

Worked fine for me.

There was a bug, that said, wall thickness not implemented but it did it anyway.