Hey guys how you doing?

I keep having a hard time dealing with MOI3D, I just want to close that area because I will boolean this later, i tried drawing lines and snapping as the red lines show, then planar, didn't work, anyway to fix this? Thanks in advance!

Post your 3Dm for a more explicite answer! ;)

Hi Dr Bombs, how did you create this object?

The easiest way to close something like that is to keep it closed from the start by having a closed solid and then use Boolean Difference to cut the solid into pieces. When you do that then the "side walls" of the cutting objects will be kept in the result and you won't have any more work needed to close it off.

> i tried drawing lines and snapping as the red lines show, then planar, didn't work, anyway to fix this? Thanks in advance!

If it's a planar cut then I would expect that what you describe should work. Can you please post the .3dm file so I can take a look at what might be going wrong? It's very difficult to analyze geometry from a screenshot alone, it helps a lot if you can post the .3dm model file.

- Michael

Oh Sorry, and thank you, attached the .3dm file!

Hi DrBombs, if you draw in a line here:



Then you can select the line and these edges:



And run Construct > Planar to build this surface:



Then after that you can select the line and these other edges:



And run Construct > Planar again to make this surface:



Then you can select the 3 surfaces and use Edit > Join to glue them together into a closed solid, see attached 3DM.

Maybe you ran into a problem by trying to do both planes at the same time? You can give multiple inputs to Construct > Planar in one go but only if they are separate and don't touch each other. If they touch each other like you have here then you need to do them one at a time.

But it is easier in general to form a solid object first and then cut that with a line using a boolean and then you get a closed result right after the boolean instead of needing to go around and manually fill in pieces in a "patch by patch" type manner.

NURBS modeling is usually at its most efficient when you're building larger extended pieces and then cutting pieces out of them rather than trying to build 3D scaffolding and then trying to fill in individual surfaces.

There are some tips here for people coming from a poly modeling background which may be helpful:
http://moi3d.com/forum/index.php?webtag=MOI&msg=4865.2

- Michael

So what is usually the simpler way is to be more like this - start with a full solid piece (3DM attached):



Run Construct > Boolean > Difference using the line as a cutting object. That will divide the solid into 2 pieces:



Delete the piece you don't want and then it's all done, there isn't any fill in needed because a boolean cut on a solid makes solid chunks with the cutting object already combined in:



- Michael