Controlling Mill Direction of Flow

[Anonymous]

I am using the Flow operation to make a chamfer on the corner of a ramped surface, resulting in a compound corner with no 'square' edges.  In a previous file this worked without any issue, and Flow walked the cutter up the long axis of the roughly-rectangular surface as desired.  On a nearly identical model the Flow operation attempts to define the U & C flow vectors at an angle to the long axis of the fillet, and gives a "no valid geometry selected" error.

Is there any way to manually set the Flow operation's guide vector?  I think the non-square corners of the chamfer face are what is confusing the software.  If it helps, the U direction appears parallel to the Z-axis plane, causing U to move across the compound-angle surface diagonally.  Attached is a roughly-isometric view of the feature with Z in the 'up' direction.  As you can see, Flow is not attempting to move parallel or perpendicular to the primary length of the face.

[mike.mattera]

You should be able to click on the red arrow to change the direction.

[LibertyMachine]

Can you share the part? I've encountered this on another file I was helping a friend with. We came to a solution, but it's not that clean. It does show the limitations of the operation as well as the sketch engine.

[Anonymous]

Did your solution involve just sketching the toolpaths direction for Fusion to trace?  I'd done that before finding out that Flow worked more easily in the past, and I can do it (fairly easily) again here if that's the workaround.

I'm sure the issue is that there's several fillets & chamfers intersecting at this surface, and it just results in a weird trapazoid/parallelogram shape that is confusing Fusion about its primary direction.  It would be nice if we could manually override this detection algorithm and just select the edge/vector we want the tool driven along to sculpt the surface.

[LibertyMachine]

Not quite. Easier shown than typed, but I'll give it a shot:

Offset Plane > Zero Value. Select the face you are trying to machine. This gives a new work plane.

Sketch > Project. Project the face of the chamfer onto the new plane. It might not give you everything you need, so feel free to use traditional sketch methods to create a closed entity.

Patch > Create Patch. Select the new geometry to create a surface patch. Make sure that it's pointed in the correct orientation. If it's Bronze, it's upside down

Select this face in your Flow toolpath. It should be going the correct direction

[johnAA35N]

I've got this same problem, and am trying to implement your solution.  If I understand correctly, the main issue is to somehow hack fusion to make it change the orientation of the isocurves so that the UV directions make sense for machining.  I'm unable to do that.  I've tried using construction planes to create patches, but everything I try maintains the UV directions of the original model.  Very frustrating.  In Inventor, there is something like "change sketch orientation"  but I can't find anything like that in Fusion.  I could see how that might work, because you get to fiddle with the orientation.  Perhaps I don't understand your solution.  I very much would appreciate any help with this.

I've seen users rotate a texture that is applied to a surface using the appearance tool, and editing a texture .  That is so very close to what Flow needs.  If I could rotate the Flow path based on an angle from a U or V line, and click on an edge to set that angle, I would have what I need.

[postX3TRX]

Use entry position. ex to make it start from bottom and up etc:)