Bass Horn Part 6

Working on the valve block today didn't go quite as planned. I had hoped that the valve caps could be on top like they are on the French horn, but with the paddles flipped and the relatively short paddles, I couldn't fit the tubing around where needed, but most importantly get the correct height for the linkage to move freely.

I'm sure if I had more time I could machine a solid rise to sit between the two supports and the linkage bar, but trying to shim the two spots and still not achieving the right height was leading to more headaches than necessary. The work-around was to flip the section back over like you would find on a tuba... Sure you can still have access to the rotors for maintenance, but it loses some of it's Professional-Quality-Appeal. This does move the valves down and up a little, and should give me enough clearance to still depress the paddles. It should, if I wanted to and had better skills in the future, allow me to flip the valve section over again and use a new linkage set - maybe even strings!

I also filled the first branch after the valves with Cerrobend and bent the end toward the valve block. In draining the oil from the tube before filling with Cerrobend, I noticed a small crack in the seam. It's a little worrisome as this might lead to more crack, but it's in such a spot that I can cover it with a brace. Found a ferrule to fit the tube that I had torn through (old stupid mistake...) and made a ferrule for the two new inner branches. Then I cut the ends of the new inner branches and fit them together, then cut the first branch connecting to the valve section to the proper length to bring the tubing around as it should.

The current total estimate length, through the valves, leadpipe, two branches, body, throat and part of the bell (maybe) is around 178.5", this leaves me with about 37.5" to add between the leadpipe and the to inner branches. This is where it gets tricky....

I need to add the main tuning slide, but leave enough room to either cut tubing out to adjust the pitch up, or add a longer tuning slide to adjust the pitch down. This of course means I need to figure out the bell situation...

At the moment, the bell is in two parts. I have a throat from a euphonium/baritone bell, it fits the body collar perfectly and is just about the right length to fit with the design. The bell is the flare from the mini sousaphone - 19", again a near perfect fit for the design. The only problem is that the tapers of the two are different, meaning that I either have to make a new throat and mate it to the bell, or add a right of brass around the section where the two ends meet. The former would involve serious brazing and cutting tabs to join the main throat and then more tabs to join the ends with the bell - possibly more trimming of the bell inner throat. The latter would probably involve less work, but would look much worse (in my head). Of course if I could find a small 5.25" sousaphone collar, I could have a removable bell.

This is the next goal, although I could always start on bending the first and third crooks.

Of the parts I still need:
Braces (I should have the right ones)
Possible second valve crook from a King tuba/sousaphone
Possible trigger mechanism for the main slide and a thumb lever
Some other things I might think up...

Finish-wise, I buffed the leadpipe, though it has been drained of pitch as I still might need to bend it more or bend it back. When I'm done with it, I'd like to get it bead-blasted with bright trim and then a coat of lacquer, but that's just wishful thinking at the moment.