Hollowing out a cylinder in a box

[Globey]

Esteemed AUGI Colleagues....

I was toying around with the 3D capabilities on Autocad (rel 2008 ). I have absolutely no experience in 3D aside from what I printed out from the help menu.

I was creating a box, with specific dimensions, then inside that box I put both a cylinder, and a circle with equal dimensions to the box in regards to depth.
I was having a heck of a time trying to hollow out that cylinder/circle in the box, so the view would show a hollowed out space rather then it being part of the box itself.
I was successful twice. I noticed once you put that cylinder or circle inside of the box, they become one. Also when I try to use the 'Subtract' command, assuming that was the right command to use, it only worked once or twice.

What am I missing? I know it has to be simple. So what is the simplest way to show a holllowed out object within another object?

[Ed Jobe]

If you just want to use a cylinder to create a "hole" in a box, then use the subtract command. If you need more holes, create more cylinders. You can't use the same cylinder to make multiple holes, but you can copy it to each hole locations. Unless you meant something else when you say "it only worked once or twice".

[david_peterson]

Assuming it's a simple extrusion, can't you create a region out of line work and extrude the region. I'm seem to remember some trick like that.
Been a long time since I've played with Solids.

[Globey]

If you just want to use a cylinder to create a "hole" in a box, then use the subtract command. If you need more holes, create more cylinders. You can't use the same cylinder to make multiple holes, but you can copy it to each hole locations. Unless you meant something else when you say "it only worked once or twice".
Thanks Ed....
What I was trying to do was to just figure out how to put a hole, like a screw hole or bore hole through a plate in 3D. When the image is rendered, it rendered the whole thing as one, rather then showing a hollowed out section for the hole.
In looking at the guidelines again, apparently subtract is the way to go, except somehow I was on the wrong plane.
I will have to delve into it more this afternoon if I can sneak in some time.
It would be easier if I had some tooling drawings, or something to work off of. As is, I'm just coming up with things on my own without anything to reference.

[Globey]

Assuming it's a simple extrusion, can't you create a region out of line work and extrude the region. I'm seem to remember some trick like that.
Been a long time since I've played with Solids.
Once I figure out how to use those terms, I'll give it a shot!
Thanks Dave!

[Ed Jobe]

When the image is rendered, it rendered the whole thing as one, rather then showing a hollowed out section for the hole.
In looking at the guidelines again, apparently subtract is the way to go, except somehow I was on the wrong plane.
Sounds like your cylinder was on top of the box rather than through it. Just move it in the z axis.

[Globey]

Sounds like your cylinder was on top of the box rather than through it. Just move it in the z axis.
I know the issue you're talking about. I have moved past that. I had made my cylinder flush with the depth of the box.
One way I know it works is to draw the square, to whatever length/width/depth, separately, apart from the square, draw your cylinders, where your depth should be equal to or greater then the depth of the square, then move them into the square itself to your desired location.
Then you use the subtract command to subtract from the square itself, the diameter of the cylinder. It will automatically cut out the hole, along with removing the cylinder.
I know there must be a less time consuming way, but so far, this is what I know works.
I can't wait until my 3d modeling classes begin at school later this year, but I do want to try to have a rudimentary understanding of modeling beforehand.

[david_peterson]

one other thing you can do is to both "profiles" that way want them. When you extrude the cylinder, extrude like 2' longer than the "box" and move @0,0,-6 or so. this makes sure that you will cut all the way through

[nextvkin]

Presspull is a good way to make holes in a solid - after creating the solid, draw your circle, or whatever shape, on the surface (with DUCS on, the circle will be drawn on the surface your cursor is on), then use presspull - pulling down will result in a hole, pulling up will result in a cylinder.