by jorge » Sat May 09, 2015 4:28 pm
Welcome to the forum Jason. Depending on how robust the wood shell is, the bands serve to either reinforce the strength of the shell or just decorate it. I personally like the look of bands and also have congas with relatively thin shells that do benefit from the reinforcement.
If you want the bands to serve a strengthening purpose, they should be mounted on the shell and, before attaching them, tightened by tapping them toward the fattest part of the belly of the drum (either up or down). I use a large flat blade screwdriver and rubber mallet and go around a few times to make sure each band is even and relatively tight. I don't know where you live but the best season to do this is winter or early spring when the wood is dryest and has shrunk somewhat. In climates with large temperature differences between winter and summer, the wood shell tends to expand in diameter with the summer humidity and shrink in diameter with the winter dryness. Once you have the bands mounted moderately tightly, enough to hold them in place by themselves but not so tight that they will pop with summer expansion. Cuban congas often have hardware that is not very strong so be careful not to make the bands so tight that they will pop the rivets or welds when the wood swells in the summer. You mainly want to keep the bands from buzzing when you hit the drum. Mark the hole locations, and drill pilot holes (eg, 1/16"). I would use wood screws not rivets to hold them in place, and definitely drill pilot holes for the to keep the screws from cracking the wood. The wood screws and the pilot holes should not go all the way through the shell, there is not a lot of force on the screws. If your new band locations are different from the old, after you mark the new holes but before you screw the bands back on, fill the old holes with Plastic Wood or sawdust and glue, sand lightly and refinish each little spot. The drum should be airtight, even a small hole can affect the sound a lot.
I have had to tighten the bands on all of my wood congas (oak, cherry and ash), sometimes I wait a few years to get a sense of how much difference there is between summer and winter. If they are loose in the winter, they sometimes buzz or ring and you can temporarily stuff some paper or cardboard behind them to prevent that. It is better if they are tight enough to contact the wood all around. Sounds like your conga does not really need them for structural strength, so you can wait until it is winter in your locale, no big deal.