Posted by bloke on February 07, 2004 at 21:13:37:
In Reply to: venting posted by scottw on February 07, 2004 at 20:34:59:
This is beneficial, particularly when done to valves of slides that are manipulated.
This job is easy using an "aircraft" (12" long) drill bit and a low-powered (rechargable) variable-speed drill.
It is best done well ABOVE the center point - but still obviously not to high to "not work". An inspection of the interior is highly advised. Often, the "undercutting" of the interior knuckles defines that the "center" of the inside is NOT the same as the center of the outside.
Realize that (particularly on a short-1st-slide tuba like a 186), afterwards there will be no vacuum to hold the slide in - when the instrument is sitting on its bell.