Do we have to use supports all the time for our prints?

I have been looking at a few of my drawings in the form software and it looks pretty clean and straight forward.  I like the use of red to indicate the areas that need support for safer printing.  One thing that interested me though was a Goldberg-8-3  sphere I downloaded from somewhere.  When I loaded it into the software it shows no red areas!  Does this mean it can be printed without supports?  I suspect not because of the small contact area there will be on the plate,  but how can we manage these decisions, is it something that comes with a little practice and not just looking for the red!

Interested in peoples thoughts.

I have attached a form file with the sphere at 3.5" for folks to look at.

Hey Nigel,

The red “supportedness” only appears after supports are generated. For now, you’ll have to use your best judgement to determine whether or not a print would work without supports. There’s some additional information about support structures here:

In this case, the part you’ve attached would require supports to print well.

Craig, thanks for that.  You know I have imported several items into the S/W yesterday and for some reason it did not register that there was no red before I added the support structures!  I can see it now.  I have been through the support documentation previously so I have seen the referenced page.

Onwards. . . .