Knife Tool

Hi, I’m new with Blender and I don’t know how to use the Knife Tool. I hit K, select Knife (Exact or Midpoints). I beginn to draw with the little knife, hit the right mouse button and… nothing! The cut is dissapearing when I hit the right mouse button.

ahh. this is kinda hard to figure out. after drawing your cut, it is deactivated by right mouse button. you need to press Enter when you are finished drawing your cut to have it take effect.

Yup, is hard to explain to. But is importand for me to find out. I add a plane. I’m in Edit Mode. The plane is pink. With the knife tool I draw inside a free circular form (like a hole or something) But when I hit Enter or right mouse button the form dissapear. Nothing. I must touch the vertex with the knife tool or something? Link one vertex to another with the knife tool?

Yeh something like that. I’m not much for the knife tool actually. Could be just because I haven’t figured out its beauty yet, but nevermind.

However, it should be based upon ‘touching vertices’ as you said.

Best of luck with it ^^

this can not work as the knife tool only works on edges. hence if you have a plane subdivide it a bit until you have a grid. now select all edges you want to be affected by the cut (all others not selected are not affected, usefull to cut only certain edges). then draw the cut with the knife. imagine like you really ‘cut’ the edge hence best is placing a click on one side of the edge, cross it in 90° and place after it another click. go on until you have the shape and press enter. each at each crossing point of the knife-line and an edge a vertex is inserted.

best way to use knife tool though is to select an edge and cut it at one particular point. yields for me the best results.

EDIT: for your task though a different approach is better. create a plane. then create a cylinder. erase one side of the cylinder. select plane and cylinder (now circle) objects. hit CTRL+J to merge them. now go connect the vertices of the plane with that of the circle with faces. then erase the old plane and circle faces (would you do this at the beginning the vertices and edges would be erased too).

Sorry to say this but blenders knife tool has no beaty :frowning: hopefully they will improve it once we get n-gons or somthing.

Hmmm, shouldn’t this be in blender general?

That said, I find the knife tool very handy when I need to use it. Sure, it could be better with regard to the unnecessary edges it adds but still, it has a purpose and with a little forethought - and a bit of post-knife surgery - it gets the job done.

This should be in blender general, don’t forget about the loop cut tool (CTRL+R).

I think the knife tool is pretty bad, cause you can’t do more than one cut at the time. But when you need it it’s good. It makes tris why it should squares.