An issue with the Knife tool.

I’m sure all of you are already aware of this issue as the problem is in me and not exactly the program. So here’s the deal: I want to master this tool and want to ask how I can prevent or otherwise fix the artifacts that appear in the vertices after I push the Enter key to confirm the cut line. I want to prevent them from appearing so I can keep the mesh as clean as possible so I can make it afterwards deform naturally, a problem I’ve seen plenty of people around here encountering while modeling. Just another harmless noob question.:stuck_out_tongue:

Knife mode works in two ways

Exact cuts the edges exactly where the cut line crosses it.
Midpoints Cuts the lines crossed in the middle.

You get a lot of triangles because Blender doesn’t support Ngons but if you use the midpoints mode you’ll get a cleaner mesh.

I think the next version will have a vertex snap mode for knife which may allow for cleaner cuts.

Also, Zbuffering doesn’t work for the knife tool so only select the areas that will be cut.

There’s also knife multi cut, which would allow you to have two or more cut lines along where you drew the cut line.

The knife tool is great but has some issues. If you’re aiming for an all quad model, you should hate N-gons more than you should hate triangles.

Your first issue: You want to keep cutting across the other side of the model? You could use subdivide too. But use it so the selection is subdivided in the lenght only. You will end up with triangles at the ends, but that is easy to convert into quads manualy.

The REAL issue with the knife tool is that you’ll get very very messy loops if you make S-shaped cuts. It isn’t apparent right away and it can be fixed. For a more in depth explenation, read the post halfway the screen: http://www.subdivisionmodeling.com/forums/showthread.php?t=907&page=4

Okay, one more question. What is the method for filling the holes you create while removing triangles or just vertices in a common way?

Thanks for the link too. This has given me yet another boost with my long and bumpy road to completely get the workflow of Blender inside my head. Slowly it does.:wink: :stuck_out_tongue:

You could try Shift F to fill holes pressing the beauty button for better results. Or you can just select edges and vertices and do it manually by pressing F.

If I read you right, you mean to say that removing triangles realy means deleting them? What I would mean by saying “removing the triangle” is that I would make it into a quad. The way to do it is by cutting one loop (what you think is best) that ends at this triangle. It will become 2 triangles that can be joined into a quad.

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That is a technique that I’ve found to be easier than other ways a lot of times. Just delete the tri faces in the ‘bad’ area, then decide how you want the quads to go and select 4 verticies at a time and hit ‘F’ to create a new face. You have to do it one face at a time, but you pretty quickly and easily end up with the quads in just the configuration you want.
This works best when you’ve got some tris stuck in a corner or something. If you’ve used the knife tool and ended up making a whole loop of tris, then you were better off using the subdivision method to begin with.

Try the CTRL-R (+move mouse over edges you want to cut, click to select, move mouse to adjust, click to finalize)