Posted by Chuck(G) on July 05, 2001 at 23:35:25:
In Reply to: Porting of valves posted by Charles Knight on July 05, 2001 at 21:15:34:
If this is a rotary valved instrument, the operation is simple (drill a small hole in the casing, smooth the inside burr. Many rotary tubas are manufactured with ported valves.
If this is a piston tuba, the operation is a little trickier regarding hole placement in the piston and perhaps there are questions of hastening corrosion from the inside of the piston.