Hi Brendan,

> I can't seem to shell out the attached solid? I've used Offset>Shell and also Offset>Inset and the
> function fails to make any changes. Any ideas?

Shell is easily confused by little perturbations in surfaces, part of how it works is by generating offset surfaces and an offset surface tracks along the surface normal of the original surface. If the surface has wrinkles in it or worse yet folds back over on top of itself those get magnified on the offset (think of the offset being like a stick on the surface, any little wiggle at the base of the stick is magnified at the tip of it).

In the back part of your model it looks like there is a self-intersecting or "folding over itself" part in these areas here:




> Also the Fillet>Fillet function does not seem to work for the junction of the fin and fuselage base (not
> that I'm too worried). I selected the seam and and started with a fillet of 0.1mm but no go, also
> any ideas on this?

Fillet also involves generating offset surfaces and then intersecting them with one another, that's part of how it forms the path for the fillets to follow. So anything that hoses out offsets will usually also break filleting in those same areas as well.

- Michael