Issues with func_physbox: hitbox falls down from the brush

Since shortly I started working with Hammer, I had several issues, but this one is one which I keep noticing.

Whenever I create a func_physbox, and parent it to a prop_physics entity, the actual hitbox of the func_physbox brush just falls on the floor, resulting the brush itself to have no collisions on other entities.
Here is a example:

The idea here is the fan itself can wobble, but the problem was it also spins around on its own axis, which is not supposed to happen, so I made a little mechanism.
The bar is supposed to minimize the spinning, but due to the hitbox just falling on the floor, the bar doesn’t make any collision with the nodraw brushes.
What should I do? This is very annoying.

If I’m understanding this right, couldn’t you just use a rotated phys_keepupright?

I’m assuming you have the prop_physics held loosely by the nodraw ring so that it will wobble, but you want to prevent it from spinning like a normal fan would?
If so, use a phys_keepupright and set the angle to “-90 0 0” (this may be wrong, but play around with it; I’ve never used this entity before), and have the max angular extent to whatever you want depending on how much you want it to be able to spin.

The problem is with a phys_ballsocket is when a entity that is attached to it, it can can spin around, and I have never seen a ceiling fan which has itself spinning around and rupturing its wiring, instead of the blades.
This ceiling fan which came from CS:S, uses two individual props, the base, and the blades themselves.
In my case I only want the fan blades to spin around, and allow the base itself to wobble like a normal one would.
Anyway, I have been playing around with the keepupright entity, still no go yet. I’ll try some more.

[editline]27th October 2013[/editline]

Quickly recorded a video to show the issue here:

So before shooting, the fan hangs nice and steady, and just the blades are moving, when shooting it it wobbles (which I like to) and the whole thing spins which I don't want to happen. That's why I tried to make that bracket to limit the wobbling and to limit the spinning.