I am working on a Buick drum conversion. I decided I would try to balance them. Before I have just put them on the spindle and added weights to them until they did not seek a position. I wanted better. I had an old wheel bubble balancer. I could not adapt it. I made an insert that had a point and went inside the hub and registered on the lower bearing. A bulls eye went on top of the hub. I fooled with it until I could put the drum in any rotation and have the same weight/position to get a balance. The bulls eye cost $2.20 and the rest was scrap. The tube is pipe and the top and bottom parts were cut from plate. I still have to install the weights and adjust them. I hope it works!