Eric R Snow wrote:
Is it a bowl? What's the capacity?
Yes, with a center cone. It is nearly 2 gallons full, but I don't think
I'd run it full. 12" diameter.

Some of the machines have an
adjustable weight to vary the amplitude. You should see a good mixing
action when it is running.
I see a vibrating, rolling action, very little side-to-side
displacement. The rolling is such that the medium comes up the sides
and down in the middle. The medium also rotates around the bowl. I
think that I'll experiment with different weights & see what happens.

Is there any noticeable displacement when yours runs?

If you are going to use water in it then
that will also change the action.
I don't know if I'll be using water, but I built it so that I could (tight).

How did you build it?
I used a 20#/5 gallon propane tank. I cut the bottom off for the bowl
and used the top as the stand. A tread mill motor with an eccentric.
Lawn mower valve springs for suspension. I'll post pix when I've gotten
all the kinks out.

Bob