create a plane with 3 points on a mesh

[SC_Precision]

I have a pretty large mesh that comes in quite far from the origin and way out of any workable alignment.  I'd like to add a plane to it, in order to help me more efficiently move and orient it to the XY plane.  However in mesh mode, I try to add a plane using 3 points, and the first two "seem" to add fine to the mesh, but when I select a location for the third point, the plane forms off in some wild orientation.

My end goal for the mesh is ONLY to use as a visual guide for creating geometry, I am reverse engineering a part to fit to this mesh.

Any thoughts on this?  Thanks as usual.

[Anonymous]

Regards!! can you please post an image or screencast to see better your idea???

[SC_Precision]

It's really a basic question for you guys that are experts, keep in mind I am a novice with Fusion.  Just trying to add a plane to a mesh. 

1) In mesh mode, I select "create plane from 3 points"

2) I can click the mesh, and it appears I have succesfully added the first two points to the mesh.  See "point 1" and "point 2" screen captures.

3) when I select the third point, it does create a plane, but it is very far from its expected location and orientation.  See picture "the plane"

Hope the pics help but again, its probably a super simple issue I am fighting...........and thanks!

[Anonymous]

it doesn't matter if is a basic question, always an image can offer a better way to see the problem. 

I do in three different models and it works fine for me. take a look.

if you can shared your model i will take a look to make this construction plane with it.

[SC_Precision]

Agreed - a picture is worth a thousand words.  Whats a video worth then?  I need to learn how to capture video.  Are you using something like camtasia?

Anyway - that is very interesting - you are creating a plane exactly like I expected to!  Let me size down my mesh and get something "shareable".  Thank you for helping with this!

[SaeedHamza]

Hi,

Did you scale down your mesh before you tried adding the plane?

Regards

Saeed

[Anonymous]

you can used SCREENCAST, find it in https://knowledge.autodesk.com/community/screencast and its an autodesk official product.

[SC_Precision]

No Saeed, not yet.  I will try later this afternoon (East Coast time).  However, I am not sure if I can get it small enough to still be effective for the detail I need to see.  I will try deleting a lot of the mesh, such as flat surfaces especially.  I know I need to get better at reducing the mesh to a more efficient size but am afraid to lose resolution where I need it. 

Update to follow.

[SC_Precision]

Screencast looks good!  I will also try that as well, thank you.

[SC_Precision]

Well, I have this mesh in two different files.  One, I have moved the mesh around and oriented it,  this file will not take a 3 point plane. 

I also have the exact same mesh, in another file that is untouched, and I CAN add a plane with 3 points.  So apparently size doesn't matter.

Makes it more mysterious now but, I need to move past this and next time I will add any planes at the instant I import and before I start moving the mesh.  at least, that works for the plane I KNOW of at the time. 

I could make the file available somehow but the mesh is about 90Meg.  I think I am on  my own with this one but something is going on as I had the exact issue a couple months ago on the last similar part I had done, and bailed out on it at that time as well.

[subversivespeed]

I am using an OBJ and it also is not working for me. 

Well, i take that back... It DOES work, however, it projects the plane in space somewhere, but not touching the 3 points. it projects it on one of the origin planes. 

Seems like there is some wierd thing going on, some mode that needs to be changed. 

[subversivespeed]

Ok, it looks like its an issue with the file. I have 2 files that I converted using Remake, and converted them into QUADS and they seem to function correctly. However, the raw OBJ files I have from Skanect seem to be at issue, and they simply project the plane to who knows where. 

It must be some sort of incompatibility.  I did the same with the "AXIS THROUGH 2 POINTS" using the mesh cloud points and had the same issue: it made the axis, but sent it off onto the one of the ORIGIN planes. 

[subversivespeed]

Here you can see the 3 point plane tool worked correctly with 2 other mesh bodies.. However, when it was used in the engine bay, as shown in red to highlight the selection points, the plane is offset and not really even the correct angle.

[subversivespeed]

Ok, update: 

Oddly enough, PLANE CUT was able to make a proper sketch of the silhouette AND generate a correct plane, so, this points to a bug in the 3 POINT PLANE routine. So, that is one workaround if you really need it. May not be as accurate, however, you can tweak it and get pretty close. 

So, I did a PLANE CUT, found the sketch that was generated by it, hit "edit sketch", and it showed the blank sketch with the silhouette of the body. From there, you can make a sketch and start using it to design from it. In a way, its a better workflow than using 3 point plane on a mesh body, and, it works so far with ALL mesh bodies, rather than just some of them. 

[luciacasu]

Hi @Anonymous,

can you share the .OBJ file?

Thanks,

[subversivespeed]

Correction; everywhere I said PLANE CUT please revise to MODEL: CREATE MESH SECTION. 

Simply choose this feature, click on the mesh you wish to generate a plane from, then adjust its accuracy while watching the crosssection. It likely won't be perfectly accurate as a 3 point plane, but it does work reliably with all the objs I tried it with recently, esp. the ones for which 3 point plane will not work. 

That creates both a sketch based on how you position the plane, the crosssection and a plane for you to use. Hope this helps. It works with ALL my objs. 

[subversivespeed]

here is what I ended up with, and, its not perfect, but, its useable until they get the 3 point sorted out.. Hope this helps.. 

[SC_Precision]

I really look forward to getting back to this issue. I can respond soon, but now in china on business and may not have a chance for a few days yet. Some info looks promising. And yeah subversivespeed, sounds like we see the exact same thing. My plane would just end up in some crazy location and angle.

[subversivespeed]

I have to admit that I am glad that this happened because it forced me to use the CREATE MESH SECTION which is actually better than how I originally planned to do this.