Of course, congueras is the correct spelling, my typo.
Thanks for the responses, specially roberthelpus.
I live in Europe so will have to get my rings locally.
5 to 6 mm seems good for me, and indeed regular steel might just be good enough, I don’t have high humidity around here.
At Latinrhythm Traders I found this information about steel rings:
Made from 1/4" steel, ranging from 6" to 16.5" in diameter in 1/2" increments (1/4" increments between 8" and 15"), our steel rings work great for a variety of projects and drum builds.
http://www.rhythmtraders.com/African-Dr ... s-p34.html