Feature Request: Internal Supports

[AK_Eric]

I did a search and was surprised to not have seen this. In case I missed it:

I'd love the ability to have internal supports. There is infill, yes, but I feel we could have something better, when you're not concerned about structural strength : Infill is great if you want to make sure the part won't be crushed by your kid. But if you're getting into sculptural work, and large scale printing, infill can waste a lot of time and material.

What I'm requesting is the ability to have the same type of supports we have on the outside of a print, on the inside. They could be used in conjunction with infill, or by themselves.

I recently printed a live-size head zbrush sculpt on my C-Bot:
http://www.akeric.com/blog/?p=3477
I gave it 5% infill just so the "roof bits" of the head that were unsupported would have something to print on. It still took over 31 hours.

But, I would have much preferred instead to have no infill at all, and only print "internal support" where it was needed to hold up any top bits that are past an acceptable overhang angle. I'm pretty sure that 31 hours would have dropped substantially, plus the overall cost of the print.

[Stefan_Koch]

+1 from me. More control over infill / internal support would be great.

Especially, a feature like "Infill only where needed" would be a killer. Slic3r has such a feature, and I used that very often. If you activate it, Slic3r just puts infill in areas that have overhang angles above the threshold declared for support overhang. Especially with organic shapes, that saves a LOT of printing time and filament. I´ve had objects that needed 85 % less infill with this feature.

Of course, having different variables for support and infill overhang threshold angles would be best, as you can probably get away with a higher angle threshold on the infill, as it won´t be visible.