Hi,
I'm using Slic3r 1.2.9, and found that when I fill a solid object, it doesn't join the infill to the perimeter. This means that the piece is much weaker than I want.
Below is a photo showing a couple of pieces which I've broken open. Top is a sphere which I expected to be filled completely with an infill, but as you can see there's a narrow pillar of 3D honeycomb (I think) up the middle, and a large space around it. The outer diameter of the ball (which is printed inside a socket, in case that's relevant) is 50mm. Below is a triangular piece printed at the same time, 10mm thick... again, there's a 1-2mm gap between the outer wall and the infill
Infill settings :
Is this a consequence of "Only infill where needed" being selected?