How to project a face onto a surface?

neobobkrause

OnShape still doesn't have 3D sketches. So in leu of that, I'm working around this lacking by drawing distorted face shapes in a planar sketch, which I then project onto a 3D surface. Well, I WANT to project these sketch faces into a 3D surface. But so far I've not been able to find a means of projection. The Extrude can't do it. Project Curve obviously doesn't work, because it projects a flat sketch face into another flat sketch. I've also tried using Project Body by @MBartlett_Tek_Pac, but it doesn't allow projection onto a lofted or thickened shape.


This document shows a simple characterization of the challenge. How can I project the flat shape onto the surface of the 3D shape above it?

Thanks for any help.

- Bob

mlaflecheCAD

@neobobkrause If you choose the sketch instead of the face it seems to work, unless I am missing something in your request.  I made a copy here:  https://cad.onshape.com/documents/f52aa59f46d278b6f51909e6/w/f5c42223fa68b6e2cb731b35/e/3dd0ca5c7f793b8cd594cb56

mlaflecheCAD

@neobobkrause
You can take a 2D sketch profile and use the split function with the faceoption.  https://cad.onshape.com/documents/55b09bd496928d244a6d5b8a/w/8c4d36c87035a3cbee788120/e/f46326753b212304a8f8fdac

This curve can then be used for a variety of purposes.


Also note there are many 3D Curve creation tools that are available in Onshape as well.

Projected Curve takes 2 sketch profiles and makes a 3D Curve
3D Curve will create a spline though points in 3D space
Bridging Curve will create a curve with tangency and continuity

neobobkrause

Thanks, @mlaflecheCAD!

But Split only works when the tool surface fully intersects the projected solid. So, for example, it the flat rectangular solid in the demo document I linked to above was taller than the 3D shape above it, Split would still fail because the 3D shape doesn't intersect fully.

mlaflecheCAD

@neobobkrause If you choose the sketch instead of the face it seems to work, unless I am missing something in your request.  I made a copy here:  https://cad.onshape.com/documents/f52aa59f46d278b6f51909e6/w/f5c42223fa68b6e2cb731b35/e/3dd0ca5c7f793b8cd594cb56

neobobkrause

 @mlaflecheCAD

??? I don't even know why that works, but it does. A good reason I wouldn't have discovered this on my own is that the individual edges of the sketch have to be selected, not the face that they enclose.

Well done, Mike! This is a permanent addition to my quiver. Thanks.

EvanReese

Does anyone have a solution for this that doesn't split the underlying surface? I know I could offset the base surface, then split that. I guess I'm wondering if there's a custom feature for it already. Anybody know of one?

konstantin_shiriazdanov

@Evan_Reese there is this one - Project with a variaty of methods

EvanReese

konstantin_shiriazdanov said:

@Evan_Reese there is this one - Project with a variaty of methods

Exactly what I was looking for and more! Thanks.