I expect it would depend a lot on the characteristics of the powder, but I've seen a conical dispenser with the output blocked by an inverted conical plug for dispensing powder. I expect you will just have to try things and see what works.
I expect it would depend a lot on the characteristics of the powder, but I've seen a conical dispenser with the output blocked by an inverted conical plug for dispensing powder. I expect you will just have to try things and see what works.