Are you talking about the kind that uses walnut shells? If so I wouldn't bother trying to use it.. I have a tumbler and use aquarium gravel and a little soap and water in it and I usually let it tumble for an hour or so depending on how clean I want the coins to be.
If it is a tumbler it will work with the right media loaded in it. If you are speaking of one of those vibrating units, it probably doesn't give enough "action" to clean coins. I bought a rock tumbler many years ago. It is used for rocks, ammo reloading, and cleaning coins.
I'm curious if tumbling is too "rough" on the coins. I would be hesitant to tumble any older coins. I think it would be great to clean up the clads for re-circulation.