Posted by Vented on January 11, 2000 at 21:53:00:
In Reply to: Venting posted by Daryl on January 11, 2000 at 17:19:20:
If you study the arrangement of tubings, you may see something like this:
Typically, the middle 'short& straight' passageway in the valve is the return path from the loop of the valve slide on to the next valve when the valve is down. The bottom angled up passage is the one that actually goes directly from one valve to the next valve when the valve is NOT used.. ( See how the straight on through the valveset path is actually a zig-zag! ) The hole is usually drilled below the short and straight tube of the piston, next to the tube passage that is angled. Sometimes there is already a circle on the surface of the valve from the edge of the valve loop. This is the area which is exposed to the valve loop when the valve is in the UP position. When the valve is DOWN, the drilled hole will be against the casing wall. You don't need a big hole. Moving the slide will vent the air through to the the INSIDE of the piston and out the bottom of the casing. You will hear and sometimes even feel the breeze. Note: This will also eliminate any suction that might hold your vertical slides in place. Be careful of which ones may slip out due to gravity either while playing or if you set the horn on its bell!