Why filleting??
I've redone central ridge using G2 Blend:try to play with the bulge slider to see when it match kind of filleting you want
see my screenshot

That's great, got ya. Way simpler, but I would like to know why I can't fillet on those edges, just so I know for other projects.

Hi Bdaniel,

> That's great, got ya. Way simpler, but I would like to know why I can't fillet on those
> edges, just so I know for other projects.

It's because the surfaces that you were trying to fillet were already meeting up smoothly to one another - you can only apply fillets to edges where the surfaces are sharp where they come together at that edge.

Also when 2 surfaces approach very closely to being smooth but are only just barely not actually smooth that becomes a pretty difficult situation for the filleter to deal with, because part of the fillet calculation involves doing an offset of the surfaces and then an intersection between those and 2 surfaces that meet at a shallow angle usually have more of a sort of "area of overlap" rather than distinct clear intersection curve between them. Filleting needs to find a clear intersection as part of its calculations.

Also 2 surfaces that touch sharply along most of their common area but are smooth just at one end are also difficult for the filleter to handle as well, that's a "disappearing fillet" situation where the fillet starts to get tinier and tinier as it approaches the smooth area and evaporates to a single point at the actual smooth spot, the fillet engine that MoI uses is not very good at handling those kinds of fillet situations either.

- Michael

Hi Bdaniel, or another way to put it is filleting means "build a rounded surface made up of arcs of this specified arc radius along these edges".

The way that is specified (being defined by an "arc radius value"), makes stuff like this work, like if you have 2 surfaces meeting up like these lines here (imagine these are surfaces as seen from the side):



Then you can apply a fillet of radius = 5 between them, which will build a connector arc of radius 5 that is tangent to both lines, like so:



But now imagine that instead of having 2 lines that meet at a sharp corner we instead have 2 curves that are already smooth where they meet like this (here I've selected one of the 2):



In this situation there does not exist any arc of radius = 5 that can be placed in between those 2 pieces, basically the mechanism of how fillets work is for applying the arc rounding onto sharp features and the way that they are specified just does not apply to already-smooth-meeting areas.

For smooth meeting areas you can instead cut back some space between them and use Blend, it's a different construction method.

- Michael

Great explanation Michael, thanks.

Bdaniel,

Do you have the blueprint images available for others to practice?

You will find those blueprints and more at http://www.the-blueprints.com/search/camaro/

Martin Spencer-Ford

Thanks!