Hi,

I wanted to make a fillet along the edges of this model in MoI (Surfaces built in Rhino) but im strugglin to be honest.....

See attached image shows the creases on the developed fillet in MoI. Also, on the opposite side of the model it seems I had forgotten
to rebuild edges on the surfaces hence why there is a short edge but MoI doesnt attempt multiple edges like this example ??

I am normally pleasantly surprised byt the filleter in MoI but this one has knocked me.....why is this please ?

Hi Paul,

> MoI doesnt attempt multiple edges like this example ??

I think what happens there is that it does attempt it, but the filleter does not handle situations where one of the created fillet surfaces is totally consumed and trimmed away by other processing such as handling the corner pieces.

So when you have a tiny edge like that (there are actually 2 over there) right next to a sharp corner, that is not a good combination and will usually fail. The tiny edge will cause a tiny surface fillet piece to be created which can then pretty easily be totally consumed.

If you use MergeEdge in Rhino to merge those little teeny-tiny edges with their long neighbors that they are smooth with, then that side will get filleted. I should be able to do that procedure automatically, I have made a note to improve this when I can get a chance to work on it.


> See attached image shows the creases on the developed fillet in MoI.

The lumpy part seems to be a bug in the fillet surface generation - it looks like the correct result there is that the fillet rails should be split into 2 pieces. Instead it is trying to build one piece in there which produces a kind of bump when it goes over the area where the crease is supposed to be.

This problem is more deep down in the fillet mechanics, I will need to send it over to the people who make the geometry library that I use to have it fixed up.

I do already have an updated library that I will be putting into V2 soon, which does have fixes to several fillet issues. I don't know yet if this particular thing is fixed in that update or not.

Thanks for posting the model file, that helps a lot to be able to repeat the problem over here. Unfortunately filleting is an extremely complex area and it will often take a while before I'm able to get fixes for bugs in this area.

- Michael

Hi Michael,

You are very welcome for the file !!

>> If you use MergeEdge in Rhino to merge those little teeny-tiny edges with their long neighbors
>> that they are smooth with, then that side will get filleted. I should be able to do that procedure
>> automatically, I have made a note to improve this when I can get a chance to work on it.

Yup that is what I did in Rhino to produce the other complete model in the file. I have been very
pleased with the filleter in MoI and have had better results sometimes than in Rhino......which is
one of the reasons I posted the example.

>> I do already have an updated library that I will be putting into V2 soon, which does have fixes
>> to several fillet issues. I don't know yet if this particular thing is fixed in that update or not.

Thats good - I will look forward to trying that in V2