I recently finished up this set of congas. They are ash wood with walnut accents. Rubber foot on the bottoms and stainless steel hardware. The interiors are turned slightly rough. The tones are pure and resonant. I'm super happy with these. I made a big mistake of using stainless steel nuts with the stainless lugs... Stainless on Stainless will seize! I used a impact driver to set the heads and the threads cold welded. Well, I had to cut them off and make new ones... now I use a copper anti-seize and standard nuts on the stainless lugs. Tunes very smoothly also.
When I was figuring out the shell dimensions and ratios, I wanted to use the golden ratio. I'm not sure why - it's not something I'm obsessed with or put into practice in other places.. but I watched something on it at the same time I was working out the sizes I wanted to use... So i made some formulas in an excel sheet just to see what would happen.. It worked out really well. I give the sheet one number (the head size of the conga) and it gives me all ratios that define the shape of the set. The congas pictured here are the first I built off this formula.
I'm excited to build some more of these! Short video here -
https://youtu.be/g-OPhjp4fYE