Have any long-time Thumler's Tumbler rotary tumbler users run into this?
I've had my model B tumbler for 10 years now. It has worked great with ceramics or pins. Brass always came out with a clean matte finish. But now this. The black crud feels waxy, and seems to be water-resistant. It does come off nicely in old corn cob media.
This is the third batch to come out crud-covered. I've cleaned the barrel between each of the last three tumblings with a mineral spirits wipe down. I'm beginning to think the barrel liner is starting to break down.
View attachment 930479
I've had my model B tumbler for 10 years now. It has worked great with ceramics or pins. Brass always came out with a clean matte finish. But now this. The black crud feels waxy, and seems to be water-resistant. It does come off nicely in old corn cob media.
This is the third batch to come out crud-covered. I've cleaned the barrel between each of the last three tumblings with a mineral spirits wipe down. I'm beginning to think the barrel liner is starting to break down.
View attachment 930479