Creating multiple polygon-faces from one polygon-face

[n_maasdijk]

Hi all,

Maybe a stupid beginner question, but i really cant figure it out.

I downloaded a 3D-model of a simple bolt and i want to make a simple partial threaded bolt out of it.

So i wanted to make about 2/3rd of the selected polygon face threaded, and the other 1/3rd part regulair steel.

But i cant figure out how to simply split that single selected polygon in 2 seperate polygons, ive been at it for hours!

And nothing what i try works sadly. The slice functions under Polygon dont work. I tried converting it to a Poly, or adding a Edit Poly modifier. I tried copying the vertexes and placing those at 2/3rd of the bolt, i tried connecting the vertexes to an edge but it really wont work from what i tried and found.

But this is probably a piece of cake for you guys, so if anyone got any ideas i would love to hear it!

Thanks already!

-Nick

[MartinBeh]

In Editable Poly, there is a 'Tessellate' button, with an options button right next to it.

You could also make a selection of the polygons to affect and then add a Tessellate or a Subdivide modifier.

But modeling the result into a nice and even thread will be quite a challenge. Instead I would suggest to create the thread as a separate object, e.g. using a Helix shape and a Sweep modifier, and then merge the thread with your bolt.

[n_maasdijk]

Thanks for the reply Martin,

But the bolts will be somewhere in the back of a still image. So i dont really need a 3D shape for the thread. I just want to make a face at 2/3rds of the bolt, give that 2/3rd of the bolt seperate material ID en then use a multi-sub object on it to give everything the right 2D-textures. So the end of the bolt will get a threaded 2D texture. 

Wich looks alrights since i have done it on multiple kinds of nuts already, but there the material ID can be the complete inside of the nut, but thats not applicable with a bolt offcourse.

[MartinBeh]

So all you want is to split the part highlighted in red in your screenshot?

If so, the 'Slice Plane' button in Editable Poly should do. Or, again, you could make a face selection (the red part) and then throw a Slice modifier on top.

If these do not work something is at odds in your Bolt mesh - can you upload the file?

[n_maasdijk]

Yes indeed, all i want to do is split the part highlighted in red.

The "Slice Plane" button was also my best guess. But it did not slice the slice anything, let alone on the desired path but it only deformed it slightly, i think there might be something wrong with the mesh then as you suggested.

But my file is linked below, so you can check it out!

Thanks again Martin!

[MartinBeh · Accepted solution]

Your mesh is probably converted from some CAD software. The long cylinder in the middle has a lot of hidden edges, which causes the conversion to EPoly to produce some weird polygons.

Go into Editable Mesh, select all those edges that make up the cylindrical middle part of your bolt, then click Surface Properties > Visible to turn them into visible edges.

Afterwards it should look like this:

With that, you can now use Edit Poly and the Slice Plane + Slice buttons

(you could do a nicer job with the visible edges by only selecting the straight edges, not the diagonal ones)

[MartinBeh · Accepted solution]

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@MartinBeh wrote:

(you could do a nicer job with the visible edges by only selecting the straight edges, not the diagonal ones)

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You can actually get this by using Auto Edge with an angle of 5 degrees: