How to mock up a horn

[Tabor]

I have used tape for a rough idea, but you only get a rough idea with tape. I typically have everything soldered together except the cluster in a mock up. Sometimes I brace the leadpipe and slap a couple other braces on, as well, just to hold it together.

[Dan Schultz]

The REAL characteristics will not be determined with such a 'mock up'. I only use taped joints and fake braces to check to see if I have the pitch fairly close.

[roweenie]

The REAL characteristics will not be determined with such a 'mock up'. I only use taped joints and fake braces to check to see if I have the pitch fairly close.

A big +1

I find it easier to clean solder than the residual gunk left behind from duct tape.

Depending on where you use the tape (ex. mouthpipe to valve cluster) even a small leak will be critical and won't give you an accurate picture.

(I always seem to get leaks when using duct tape, anyways, and not just on tubas )

[roweenie]

Gasoline nearly instantly cuts most any tape gook...and is cheap.

I usually prefer Stoddard solvent for stuff like this (I've got issues with using gasoline indoors, since my house's boiler is in my workshop room) but I agree that you can't beat gasoline as a solvent.

Sorry Mark, I didn't mean to infer you were using duct tape - that's what I used. I could be wrong, but I would think painter's tape (paper?) would be ineffectual for an airtight seal.

[opus37]

Lee Stofer has shown on several occasions that the placement of bracing strongly affects the performance of the horn. I would think that if the bracing is not in place, you would not get an accurate assessment of the horn's final performance. I think Dan is right on this one.

[iiipopes]

Gasoline nearly instantly cuts most any tape gook...and is cheap.

I usually prefer Stoddard solvent for stuff like this (I've got issues with using gasoline indoors, since my house's boiler is in my workshop room) but I agree that you can't beat gasoline as a solvent.

Sorry Mark, I didn't mean to infer you were using duct tape - that's what I used. I could be wrong, but I would think painter's tape (paper?) would be ineffectual for an airtight seal.

Yes, due to its explosive nature, it is better to not use gasoline for anything except driving a car.

[Tabor]

Here is a mock up, or perhaps a "mock up plus". I have it about to where I want it, minus the cosmetics and the bracing.



It is my second CC tuba. It is almost all King parts. H.N. White bell, King body, king valves (except the 4th valve and the small leg of the main slide is a larger bore CONN (the large side has been bumped up to .770 mirafone tubing, and the rotor is a .789 Cerveny rotor, with .8 something or other after the rotor replacing the dogleg. It is together enough to play, and it plays in CC. Decent sound and good intonation. The 5th valve is functional, but I don't have a linkage on there yet. I have had it fully functional in 3 different configurations now, partially functional in 4 or 5. I took it all apart earlier this week because I wanted the spacing with the cluster and rotor to be better, then I made a funny looking main slide to bring the cluster closer to the bell, then I put the "funny" in the exit port instead of the main slide.

The cluster is held to the horn with only four braces right now, though I have the leadpipe braced normally. I think I put one other brace on the leadpipe, but I missed the exact point I wanted by about an inch and it made the intonation want to go 5c sharp on one of the "e" open bugle tones and totally changed the feel of that "e", so I will need to go back and adjust that brace. It is pretty impressive what one brace can do. Another brace between the body and the bell just seemed to make the horn project more. It is a time consuming process to figure out exactly the best place for each brace, if that is what you want to do. Then they also have to hold the horn together.

When you check for pitch, make sure your horn is at a normal temperature or it can throw everything off. In this last round of main slide fun, I brought the tuba in and started playing it and it was hanging out just a couple cents flat with the slide all the way in. After the horn warmed up, it went sharp 10-15 cents all in, and pulls to in tune with room to go.

[roweenie]

' curious how every time I mention using $2/gal. gasoline as a solvent, there is a voiced objection from somewhere.

I use it outdoors (who likes the odor of ANY solvent indoors...??), cut it with Dawn, and then rinse.

bloke "There are eleven sousaphones here now...I don't like schlepping cases from schools. I wrote the last three numbers of each body's serious number inside the corresponding bell with a Magic Marker, and - when delivered back to the school, and just before placed back in their cases - will rub off the Magic Marker serial numbers with gas-and-a-rag. Is 'using economical gasoline for anything other than fuel' - rather than using some $20/gal. roughly-as-flammable/explosive thing instead - considered 'redneck' or something...??"

I agree that you can't beat gasoline as a solvent.