I have just built a very quick but not so dirty set up to try and get a start on my own build for a vibrating tub.
Now I do get some good vibrations but there is no flow of media. (Well, there is but it is tiny)
Is that because there is not enough weight in the excenters, are they not off balance enough (need to be longer) orrrrr....
Do I need a longer axle? I now have one that is just slightly longer than the weight and on most systems I saw have axles about the same length as the tub, with the weight at the ends?
Edit: I just found that it can also be because of small media size, sticking together because of water...
I think it was because the suspension did not give enough freedom. The tub was hung on bits of string.
After putting it up on springs the flow increased quite a bit.
Still, the very small (1mm) other media I bought for the trial does not want to flow, even if there is just a hint of moisture in it.