Posted by Jay Bertolet on March 24, 1999 at 13:17:31:
In Reply to: Re: Re: Intonation question posted by John Cooper on March 24, 1999 at 12:15:38:
What I mean by "sealing the vents on my valves" is that my rotary valves, when I used the valve slides to adjust intonation, were vented. These vents are small holes, drilled into the valve casing, that allow you to move the valve slides without that annoying "pop" you get when you engage the valve after moving its slide. Since I have no need to move valve slides on the fly, I had all the vents sealed. This reduces the risk of leakage in the valves and keeps debris from getting into the valves via the vent.
The main slide tuning stick I use is probably the same thing as the "kicker" you described. All the tubas I have are constructed with the main tuning slide in a vertical orientation. All I did was find the spot on the slide where a post could be soldered (generally on the long post between the two sides of the slide) and put it there. Then it was a simple procedure to visually sight two other places, between the post just soldered and the area where the handle would be placed, where posts could be soldered. If you can envision this, you have now three posts in roughly a straight line that you can drill holes into such that a straight rod could be inserted through all three holes. The post on the main slide is the lowermost and there would be one close to the valve slides that would be the uppermost. The one in the middle is where I put the control mechanism that keeps the slide from being completely pushed out. The only drag about this setup is that you have to detach the stick from the main tuning slide to grease the slide. With a little preparation, this is not a problem. Feel free to contact me if you have any other questions about this setup.