Tube cross section using difference boolean with good results

Hi, I’m trying to make a tube with a cut out area so that you can see inside. Like a cross section. I’m using a subdivided and smoothed cube to cut away using a boolean difference modifier.

But I’m not satisfied with the final results I get. For some reason, faces on the final render are shadowed in unpredictable ways. Anyone have some tips for how I can improve this to get better results? Attached is a screen shot showing the mesh view, solid view and render result of my object.


Instead of using booleans, try using retopo. It is the ultimate form of control over your topology. What you do, is start with a plain cylinder, put an intersecting shape where you want the hole, and then use that like a shoe/hat form to build an entirely new mesh on top of in retopo mode. One thing to always remember, is click OFF the ‘occlude background geometry’ button, which is on the main header of your 3D window. It’s tricky at first if you don’t have experience doing it, but there are a couple of tuts out there, and it’s well worth taking the time to learn.

Try to add edgesplit to your moel it may help to get rid of some darken areas

but if this does not work then you may have to retopo you hole into the cylinder!


+1 for edgesplit modifier, that should do what you want.
Retopo takes a while…

BTW, using edgesplit worked well. Next time I’ll check out retopo.

But now I’m having some kind of issue with the boolean modifier not doing its job. I’m trying to just use it in difference mode and its doing a union instead it seems. Trying to figure it out on my own for now. Maybe I have something wrong with my mesh.

Ok, I’m not sure what is going on here. I’ve attached this screenshot showing how my cutting mesh (called CuttingCube) is being joined with the mesh I’m putting the difference boolean modifier on instead of cutting away at it. I’ve done this before without issue, but for some reason, its giving me trouble. At first I thought that maybe my curve modifier had to be applied to the tube before I could cut it, but that doesn’t seem to be the case as I’ve applied that one and it still has this issue.

I’ve tried creating a few different meshes to cut with and all of them get joined. I also tried moving the mesh so its half way and all the way through the tube. Any clues as to what has happened here to make the boolean modifier no longer work?