countersink objects

Hello,
I hope “countersink” is the right english word for what I mean. As I’m a very beginner I would like to know what’s the easiest way to countersink an object A in an object B without letting faces of object B overlap the interiour of object A. For example imgine object A is the ground and object B is a bucket and you dig half of the bucket in the ground so that you can still see the bucket’s bottom.
In my particular case I want to attach screws at the round surface of a cylinder and sink them so that they are almost on a level with the surface of the cylinder. When I do so the slot of the screw is covered by the the cylinders surface so I tried 2 possible solutions:

  1. using boolean operations: when I subdivide the screw from the cylinder I get a hole where I can place the screw in but the result isn’t very satisfying and there are many unnecessary vertices then.
  2. using the knife tool to cut the hole: well it works but I think it’s a litle bit complicated.
    So isn’t there an option that I can simply make the interior of a sunk object visible without caring for the faces of the other object? I guess this would be used very often.
    Cheers
    Fluxus

In blender you have to model in the countersink.
There are a couple of different types of 3d applications – those that rely on faces to describe objects (blender, maya etc.) and those that use constructive solid geometry (CSG). In CSG applications a mathematical formula describes your cylinder and countersink – boolean operations work perfectly. In applications that use faces boolean operations must cut the faces. Booleans in blender are terrible compared to other software which use the face method but even other face oriented applications can have poor results in certain cases.

It really takes only a minute to model in your countersink once you know what you are doing

http://members.shaw.ca/rjplus/counter.jpg

GreyBeard

3d max is pretty good at booleans on faces btw.

When using the boolean functions of blender I use it to show me how the object would look and then rebuild it.

Thanks for the information, GreyBeard and whatever.
GreyBeard: it looks so easy on the image and I just tried to reproduce it. I guess you used the knife tool to cut the cylinder and extruded a circle then but I don’t understand how you got the symmetry and the round shape of the face loop around the countersink so it would be great if you explained the steps.
I’ve read quite a lot of documentation know (btw I’ve also seen your video tutorials - they are superb) but I’ve still problems to apply the tools efficiently.
Can you recomment any summerized documentation/books for “universal standard modelling probelms” like countersink, beveling, bending etc. to quickly adopt the techniques of the experts? I’m thinking about something like patterns that occur over and over again while modeling.

I did a couple of face loop cuts and then deleted one interior edge leaving a fairly square hole. I then selected the 6 verts around the hole and moved the cursor to them with the snap menu. Then while still in edit mode I added a mesh circle of six verts and filled in the faces between the square and the circle. In end view I adjusted the circle verts slightly in the vertical direction only so that they followed the curved shape of the tube.
I then extruded the hole from the circle.

I guess the important thing to remember is that if you add a mesh while still in edit mode those verts are added to the existing mesh thus allowing us to add a perfect circle of verts.

It’s a lot more time consuming to say than to do :smiley:

GreyBeard