TexasCHLforum.com

Another tip about carpet. If you go to a carpet store they usually have old samples that they sell for door mats for about $5.

I have bought several. The nylon carpet is probably the cheapest.

Another possibility is kitchen cleaning brushes. They usually have nylon bristles.

Or maybe a 10 inch Hydrotool 8230 pool brush? Only $4.75 at Amazon.

Depending on the size of the drum, I would try around 5-10 RPM for starters and adjust up or down for optimum coating.

A faster speed may generate more static, but I don't think the coating would be as uniform.

The speed should be such that the spheres and bullets roll to coat them.

Rotating the drum too fast will cause them to get too high on the wall and then fall.

Also if you have a way to introduce the powder uniformly from the front to the back of the drum while it is rotating, the coating will be more uniform.

This would require a door or latch on the end of the tumbler.

As far as generating the static - you may try different types of carpet material: Nylon seems a great choice.

One of the most significant drawbacks of nylon fibers is their inability to dissipate static electricity. In normal use, particularly under low humidity conditions, static charges can easily be generated in excess of 12,000 volts. Static charges of this level are well above the recommended maximum value for sensitive electronic equipment. To reduce the impact of static charges, manufacturers add carbonized fiber to the nylon yarn or put a conductive coating on the surface of the nylon fibers that helps dissipate static charges before they reach a level where they can damage electronic equipment.

Olefin fibers do not generate static electricity, making them particularly well suited for applications with installations of sensitive electronic equipment, such as telecommunications equipment or computers.

I am new to this discussion, but I have a couple of thoughts.

My experience has been trying to eliminate static rather that generate it.

First, you want to lower the humidity so that the static doesn't disippate.

Grounding the drum would drain the static so I think that isolating the drum would be better.