Hopefully, this might help flatten the learning curve a bit for a few folks if you are new to wet tumbling and not getting the results you want.
I'm using the FART (Frankford Arsenal Rotary Tumbler).
1) Use softened water if your local water is pretty high in dissolved solids. It helps.
2) Dawn is the standard soap. I've had good results with car wash soaps, too if the brass batch is small and not super dirty (i.e. brass fired suppressed in a gas gun). Some car wash soaps leave a little "wax" residue that keeps the brass shiny and resists tarnishing a bit. I've blended Dawn and car soap with good effect.
3) If you run a very large batch (my FART is up to 7L of capacity), you will find that you don't have enough water for the brass, and no amount of soap will be sufficient to keep the scum from redepositing. A large batch likely will require you to drain off much of the dirty water, refill with more hot suds and run it a few more minutes as a soapy rinse. I've had some especially dirty batches require 3 total drums of water to get the dirt level low enough that it wouldn't stay on the brass.
4) Hornady one shot case lube is VERY hard to remove if you don't use some really strong soap concentrations and very hot water. If your brass comes out greenish with a carbon film on it, you'll need to step up your game on soap to overcome the one-shot. Pour off the dirty water, refill with water and add 4x the soap you previously used or more. I've had to use up to half a cup of dawn for a 7L drum full of water/brass. Lanolin based lubes can be tricky too, as lanolin is generally not water-soluble without a good amount of degreaser-type soaps. (i.e. Dawn).
5) When it doubt, go heavier on the soap and lighter on the Lemi-shine. Lemi shine is just there to make the pH a littler more acidic with citrus extracts. Always remember that more brass means less water-- so you'll need less Lemi shine to get the pH in range. Overdoing the Lemi-shine will leach zinc from the surface and give your brass a copper-ish color.
6) INVEST IN A GOOD MEDIA SEPARATOR. The FAWDMS (frankford arsenal wet dry media separator) is a game changer. You can wet tumble and not lose a single pin down the drain.
If you find an older model Frankford, don't bother it. Old FARTs don't want to be messed with
H
