186 bottom bow

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bloke
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186 bottom bow

Post by bloke »

A 186 Miraphone tuba features an irreparable bottom bow, and requires a replacement.

In the depths of my memory, I was fairly sure there was one in my shop's notorious attic.

Sure enough, brownish-grey, there it was (covered with thick barn dust, and heavily tarnished.

It was originally off a satin silver instrument. (The hopeless bell - over the years - was turned into patches. Per typical with me, I probably straightened out the bottom half of it and used it to convert a King recording detachable bell to a King upright detachable bell. I remember that it had a gold-plated bell interior (such as it was). I'm thinking around 1982 or 1983, a college-buddy of mine, a fine horn player, and (at that time) a high school band director in Jonesboro, Arkansas - brought it in to see if there was any hope.

There was not. The bell was squashed flat, the kranz wasn't with it, the rotors were super-worn/rattly, the linkage was mangled. He left it with me as a "donation".

I've harvested this-and-that over the years. Last year, I harvested (though quite distressed, yet I was able to repair it) the top bow cap.

I've never needed the bottom bow, which has always looked "meh, but probably repairable".

OK, once located a couple of days ago, I started working on it.

This is one of my "keep the original bow cap installed" jobs, which are tricky, but possible.

The metal on this one behaved oddly - more springy and resistant to repair (and it sure needed repair!) compared to a typical Miraphone bottom bow (as they typically mold like clay). In a few spots, the brass peeks through, and the brass is VERY yellow - possibly very high zinc content. I remember a low-1XXX serial number, so this is probably a 65-year-old bow.

Due to the springiness of the brass (and the nickel cap as well), I've had to do a bunch of (big ogre brute-strength fingers and wrists - yeah: and major upper body muscles) hand-burnishing to get it this far.

Whoever built it really messed up the inner seam (see pic). At the factory, they put a piece of sousaphone guard wire (missing) over it to hide its buttugliness. (I'll be installing a new ugliness-cloaking guard wire to replace the missing one.)

There's also a torn flap of metal (see another pic) that I realigned and will silver-braze in place.

Predictably, it's going on a brass tuba. There's a machine shop (though I'm NOT venturing out on these ice-covered roads, and - were I to do so - I wouldn't be able to get the vehicle back up here into the property, so no...but I'm going to call him and see if (maybe?) he has a big-ass belt sander that I could stop by and use to (just barely) strip off the silver. My dent removal job is very good, but a belt sander (used very conservatively) would - in addition to giving me a huge head start in getting the silver off - also fake over the subtle dent-removal imperfections (and without making the piece too thin). Otherwise, I guess I couple pull out the orbital sander and give it a shot.

Mrs. bloke and I got a start yesterday, and - on my own - I managed to get this much farther today. (confession: I mostly screwed around today - remember? I taught myself a song. This is not one of those 1-hour bottom bows, but a "few" hours will probably get it looking quite nice...so far, I've put a "couple-or-three" in). I believe it's going to be pretty good.

I'm more than glad to do this. The person who needs it is a nice person and a fine player...and (this particular bottom bow behaving really differently from any that I've previously straightened out) is presenting a good challenge.


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gocsick (Wed Jan 28, 2026 5:21 am) • Casca Grossa (Wed Jan 28, 2026 8:21 am)


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Re: 186 bottom bow

Post by the elephant »

To me, that is a pin-up queen.

Thanks so much, man!
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tubatodd (Sat Jan 31, 2026 5:05 pm)
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Re: 186 bottom bow

Post by bloke »

Tonight I got the tear (it's on the back side, which I guess is a good thing) silver-soldered back in place, some soft solder gaps around the edge of the cap filled in, and a fabricated and installed that reverse rib on the interior radius. I also picked over the dent removal a little bit more.

It won't be fun, but I think I'm going to get the silver off of this thing tomorrow.
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the elephant (Thu Jan 29, 2026 9:04 am)
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Re: 186 bottom bow

Post by prodigal »

I don't know, I'm kinda liking it in matte silver. If it's the same vintage as mine, there is a LOT of zinc in the brass, hence her nickname "Patches."
1960 186CC
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Re: 186 bottom bow

Post by bloke »

I now know why the dents were so springy and resistant...The silver was MORE than plated. It was CLAD.
I'd guess (rather than .0004"), it was probably .003". That was a BUNCH o' silver to remove via buffing. :bugeyes: :smilie2:

OK...
If there's one thing better than meeting a challenge (repairing a bottom bow with multiple special issues, and then buffing off OUNCES of silver, it's being PAST the challenge, getting cleaned up (hot bath), being handed a good dinner, and then returning to non-challenging work.

Oh yeah: the bloke-saying:
I didn't break it.
HEY...We walked all the way down to the highway, today...
A few brave souls are venturing out.
We're not that brave. I need my cars NOT stuck and NOT down in ravines.

I'm thinking we might be able to get out NEXT Tuesday or Wednesday.
Obviously, we have power, we still have food left, the chickens are laying eggs, and I have work to do.

poorly-lit room, no flash (otherwise, all you would see would be the flash), so it's difficult to distinguish the color of the nickel-brass cap

last line to "Mr. Froggie Went a-Courtin':
If you want any more, just sing it yourself. Um-hmm.
I judge this to be "good enough" (for me, but I dunno about anyone else).

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the elephant (Thu Jan 29, 2026 6:12 pm) • York-aholic (Thu Jan 29, 2026 10:05 pm)
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Re: 186 bottom bow

Post by the elephant »

:hearteyes:
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tubatodd (Sat Jan 31, 2026 5:06 pm)
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Re: 186 bottom bow

Post by tubatodd »

the elephant wrote: Thu Jan 29, 2026 6:12 pm :hearteyes:
Welp...looks like you have a happy customer @bloke.

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the elephant (Sat Jan 31, 2026 5:53 pm) • prodigal (Mon Feb 02, 2026 2:43 pm)
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Re: 186 bottom bow

Post by prodigal »

How's the work coming?
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tubatodd (Wed Feb 11, 2026 7:36 am)
1960 186CC
B&S 5099/PT-15
Cerveny 653
A bunch of string instruments
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Re: 186 bottom bow

Post by bloke »

prodigal wrote: Tue Feb 10, 2026 6:23 pm How's the work coming?
The work on the bow itself (as seen above) has been done, but the bow hasn't been handed off.
Watch for possible (never before seen in the universe) possible pictures uploaded by tomorrow evening.

Based on what I've been told in texts, the tuba itself may not enjoy any progress until next month or possibly during the summer... but that's not my business.
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the elephant (Wed Feb 11, 2026 10:41 pm) • prodigal (Thu Feb 12, 2026 6:30 am)
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