Post #554879 by MadDogMike on Sun, Sep 19, 2010 10:42 PM

Lambda, my volcano was only 8 feet tall so I used a structure like this for the core (pardon my lack of artistic talent)

8 foot 2x4s for the legs, 2x4x4 foot box on the top. Top and sides made with 1/4 inch plywood, top has a 3 or 3.5 foot diameter hole cut in it. Bottom is open, it's covered with thick clear vinyl stretched over the opening and stapled like a drumhead. Clear vinyl avail in WalMart fabric section or use a cheap shower curtain. The business end of a fog machine (or 2) stick thru a hole in the side of the box. There is enough room under the box to stand, you fill the box full of fog and hit the vinyl "drumhead" - it shoots out a giant smoke ring.

This is the only picture have;

Because of the ceiling, the smoke didn't really have time to develop into a ring but outside it worked great. In the pic you can see from the shadow on the ceiling it is just starting to make a ring.

Not real sure how you would do this at the top of a 30 foot volcano, but there must be some engineering majors in your frat :D Let me know if you have any questions

Mike