Mirafone 186 Leadpipes

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Stephen Shoop
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Mirafone 186 Leadpipes

Post by Stephen Shoop »

Many years ago I replaced the original leadpipe with a larger one purchased from Mirafone. I still have the original and am looking for thoughts about an interchangeable setup so I am able use either when desired.
joh_tuba
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Re: Mirafone 186 Leadpipes

Post by joh_tuba »

Why not?

Just do it.
Easy Mac
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Re: Mirafone 186 Leadpipes

Post by Easy Mac »

Detachable braces can be made. You would need three of them, one at the receiver, at the center of the bell, and at the top bow contact point. A lock collar to the 5th valve is not necessary, but it helps to ensure a leak-free fit. An alternative to that would be replacing the ferrule to the 5th valve (or 1st, if you have a four-banger) with a longer bit of outer slide tubing. (You are trying to make what amounts to a super-short outer slide leg — like 2nd, but with like 3/4" of pull.) The end of the leadpipe that is straight is very short, and it is slightly tapered, so you will have to fiddle with it until it can function as a 3/4" slide that does not leak. This can be done with a flute headjoint expander or you can trim the pipe end and install inner slide tubing of the same unsoldered length (meaning that you need to have at least a quarter of an inch more to solder to the leadpipe beneath a connection ferrule).

Once you have the leadpipe-to-valve connection point completed on one of the two pipes you can wire down the three brace halves to the horn and pipe. Screw them together first, then place them where they best fit. Mark the horn with a Sharpie marker in case the brace halves shift. Make the valve end of the second pipe fit the valve in the same manner as the first one. Then wire the other set of pipe-side brace halves to the pipe as close to the positions of the ones on the other pipe as you can eyeball. Lay this assembly down on the tuba and adjust your pipe-side brace halves to make sure the locations for the first pipe will work for the second one. If so, you can solder away! If not, then you have to go back and forth, looking for locations that will line up well for the bends in both pipes. You do not want anything to be under *any* real bending stress. Everything needs to fit really well before you solder.

After some fiddling around with your braces, you will find locations for both sets unless your two pipes are noticeably different in shape. (This is very possible. Usually, you can fix this by making a thicker brace foot on one to take up a gap created by the other. As long as your two sets of screw holes line up without having to be bent you are good.

You have to keep the leadpipe "slide end" greased or it could leak, due to its short length.
Easy Mac
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Re: Mirafone 186 Leadpipes

Post by Easy Mac »

If you want a more secure connection to the leadpipe you can use a C clamp setup like on a sousaphone gooseneck. I will leave it up to you to figure that one out. It is not difficult. Making the braces is easy too if you can silver solder. They are just bits of sheet brass Dremeled into the size and shape you want, hammered over something to get them to the needed curvature, with a disc of rod stock silver soldered to each one. You drill one side to take a tap and the other one to a clearance size, based on whatever screw you decided to get at Ace Hardware or Home Depot.

Alternatively, you can give these instructions to a brass guy you trust, but who may never have done this sort of conversion. He can read this, and then alter it to his needs. I have learned how to do new things using instructions from the Internet on many occasions.

Good luck!
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Re: Mirafone 186 Leadpipes

Post by iiipopes »

Some manufacturers, like King and Jupiter, use a thumbwheel connection to attach the leadpipe to the valve block and a small thumbscrew to secure the receiver on a small bracket. Their reason is to make disassembly easier for repair in case of incident or accident. A conversion, assuming you can find the right diameter male & female fittings for modifying the leadpipe, should work well since the Miraphone leadpipe comes straight up out of the valve block with enough room to work with, even if you have to install it an inch or so above the ferrule entering the valve block.
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