filletEdge fillets beyond surface!


I am trying for the quickest way to represent radiused folds on my metal object.
As Rhino has no metal bend function :frowning: I am using FilletSrf for the inner radius and FilletEdge for the outer stretched radius.
The inner went ok, but the outer has gone way beyond the actual object, so that method is sunk, whats the fix ?

what happened and why ?
I then have to do the bends for the areas A and B, C and D,

How is it going to handle the area down at that first bend ?

attached file showing pre bend, first fillet and error on 2nd.

Is there a better / quicker method for bends ?

Note the target radi drawn to establish sizes and to ensure the ends of bends don’t end up into the radiused arch.
Measured from a real item (crashed and unbent) as best I could. Idea being to reverse engineer it.
creating a metal bend.3dm (3.3 MB)


try to use the command MergeAllFaces and create reliefs

creating a metal bend.3dm (8.6 MB)
Obround Auto Relief

I take a better start shape without a gap along base fold.
I now run command MergeAllFaces,
you then say create reliefs. Not sure what you mean there.
I do see notches at your arrows which are not on the original and certainly unwanted as cracks will grow from them.
It looks like the fillet radii are too big to go with the change in direction at their ends yet the overall dimensions of this item match that of the original, sheet steel 0.03inch thick, so as 0.05inch int rad seemed a fair ‘ask’ it must be tighter. The base plate with holes is 2inches wide, and the end plates are correctly located., so maybe a twist formed where the notch was.

I try again, on my better start shape, run mergeAllfaces, then apply the two fillets, I dont get one going beyond the object :slight_smile:explode the object and remove the end pieces and cap planar holes.
I have a nice bend to the base plate.
Now I create the external bend on ‘A’ , it goes a little beyond the archway, and doesnt follow the curvature at top of ‘A’. Why does it not flow around the curve ? I make it 0.05 radius and it wont then even select the edge !
How do I get it to follow the curve at the top, and I need to mess about trimming the excess off at the bottom.

is there a better way to get these bends in ?

other progs just bend metal, this having to construct it bit by bit trimming bits off and working out why it didnt fillet round a curve is surely wrong ?

creating a metal bend by Vikthor.3dm (8.4 MB)

Hello - you’ll just need to work at the surface level - FilletSrf, split trim - just surface modeling, at the stage you have the file in. It is not automatic, as you’d like it to be, but on the other hand, you’d be done by now…


Hello again,
look at this method, I insist on creating a ripped relief, this time only at the bottom and much thinner.
creating_bend.3dm (3.7 MB)


Hi Vikthor, and Pascal, thanks.

Vikthor, In the piece I am having to copy I have to follow its original design, and as such any cutouts can cause tears, being an aviation piece they are very careful to avoid such by having every corner radiused. Although this item isnt for a flyer I still have to replicate it following its original design.

see attached my final result. I remeasured the ‘arch’ which gave me a 0.1" rad curve same location for its top and side, but the upright started a little further out, just enough to accomodate the outer radius !
I used pipe command , as filletSrf was not following the curve at the top, on a line inset from the outer edge by 0.08inch then made two pipes 0.05inch and 0.08inch. then trimming and joining.

I think pipe will be a useful way in fact in future for such curving bends !

I like your metallic visual, what did you use for that ?

final bracket base two halves.3dm (671.8 KB)