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1928 Martin "Medium" Eb Helicon

Posted: Wed Apr 24, 2019 1:38 pm
by Tubajug
I thought since I'll be starting some work on this horn here and there I would move the discussion over to the repair forum, rather than the main TubeNet forum. The photos below are just copied from my post in the other thread. The only thing added is a picture of the polished engraving, just because that's what people do, right? Polish just the engraving? :)

But last night I got it out and looked at it a bit closer. It looks like the neck that came with it does fit, but when the tension band is tightened all the way, the neck can still move rather freely in the receiver. Is there a way to shorten the tension band to give it a more snug fit when tightened?

It certainly will need at least one bit, simply because the mouthpiece would be too far away from the player if only inserted into the neck. I am bringing home a random bunch of sousaphone bits from work today to see if any will work, then I'll ask around for purchasing one if I find one that works.

Next steps will be to remove the tarnish with Tarn-X and baking soda/water before going after the dents. If one of the bits works, then it shouldn't take much to get this thing playable. There only two loose braces, and I need to replace a cork bumper on the third valve that just disintegrated when I took the valve out (I'll probably replace all three...).

Anywho, thanks for looking and have a great day!

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Polished engraving:

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Re: 1928 Martin "Medium" Eb Helicon

Posted: Fri Apr 26, 2019 2:45 pm
by Tubajug
I took home a few sousaphone bits to try and see if any would fit into the neck of my helicon. Of the four pictured below, #4 seated the best in the neck, but I don't know exactly what brand it is, Holton? #1 is a King I believe and barely fit into the neck. #2 and #3 are Conn and went all the way in up to the bend in the bit.

I haven't gotten the horn cleaned up enough to put back together for a play-test to see if I'll need one or two bits to play it in tune either, but thought this was a good start.

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If anyone can confirm that brand of bit #4, I'll be in the market for purchasing one (or two) if anyone has some around.

Also, any thoughts on how I can alter the tension band around the receiver (holding the neck) so that it holds it tighter? The neck is still rather free-moving even with the tension band fully tightened.

Thanks!

Re: 1928 Martin "Medium" Eb Helicon

Posted: Fri Apr 26, 2019 2:57 pm
by toobagrowl
Bit #4 is a Yamaha sousaphone bit. They come in 2 angles; 20-degree and 45-degree; looks like you have the 45-degree bit.

Re: 1928 Martin "Medium" Eb Helicon

Posted: Fri Apr 26, 2019 3:35 pm
by Tubajug
I also thought it looked like an Olds sousaphone bit:

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Re: 1928 Martin "Medium" Eb Helicon

Posted: Fri May 10, 2019 10:53 am
by Tubajug
I've been messing with this a little bit here and there and it still plays really stuffy/leaky. I'm leaning more to the "leaky" side because I've flushed it with water and put some compressed air through it, and nothing has come loose...

I have a feeling the culprit is the neck. The receiver where the bits would go has a slot that should have a tension band around it, but that is gone. The previous owner was using a hose clamp, but that doesn't provide a solid seal (that's my theory anyway). When I blow into it I hear air coming out somewhere early in the horn. I've checked the neck itself and it is free of leaks (though there are cracks that have been sealed with what looks like epoxy).

My plan is to take the neck apart (brace, receiver, etc.) and test for leaks without the receiver. I have a few extra receivers floating around (a generic one from Allied and the smaller shank one from off of my H.N. White King Eb I'm rebuilding) that I plan on putting on there just to test out my theory of the receiver being the leaky party.

The bits from the post above were on eBay, so I bought them to try out. If I can get this leak sorted out, I can test to see how close to pitch it is before I start going too crazy with the repairs and clean up. Here is the neck receiver I believe is the problem:

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It's hard to see, but there appear to be cracks, epoxy, and gunk all over the back to the neck:

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Finally, the receiver on the horn that the neck goes into still has the original tension band around it, but when tightened all the way, doesn't keep the neck secure. Any thoughts on what I can do to fix that? Is there any way to trim it shorter so it has more "pull" when being tightened? Thanks for your input!

Re: 1928 Martin "Medium" Eb Helicon

Posted: Fri May 24, 2019 12:13 pm
by Tubajug
I started a different thread about stuffiness, and I'm happy to report that the help I got produced a very happy result! I found a 1940 campaign button featuring Roosevelt and Wallace stuck in my horn (button and location are pictured below).

I only played it for a few minutes and the neck is still just taped up, but with one bit in it, it played pretty closely in tune (just a tiny bit flat overall still). It has a very sweet, light tone to it. It plays pretty open (certainly compared to before!) and the pedal Eb just pops out. I haven't done much to it in the way of cleaning yet, so now I feel like I can proceed with earnest knowing that it will actually play!

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I still need to figure out how to make the receiver that clamps onto the neck hold tighter (the neck just swings around when all the way tightened) and patch/braze the cracks in the neck. Other than that, this should just take a lot of cleaning and dent work to get it up and running again! I'm just glad it plays!!!

Re: 1928 Martin "Medium" Eb Helicon

Posted: Thu Oct 03, 2019 5:08 pm
by Tubajug
I got this done in time for our alumni band performance at our first home football game back at the end of August, but I haven't posted anything for a while, so here goes!

I tried my hand at brazing the cracks in the neck and I did alright. It wasn't super-pretty, but it was airtight! That's all I need!

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Here is the completed neck with new Allied receiver:

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I obtained a genuine Martin pull ring for the second valve (thanks Tabor!):

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I polished the whole thing before removing the dents (I wasn't too picky with the nooks and crannies of the valve section...)

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I got out all the dents I could, including that big bashed in bow. It turned out a little flat, but all I had to work with were ball bearings and magnets, so I thought I did pretty well.

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I never was able to get the original tension band to keep the neck from swinging around, so I just used a small hose clamp. Works like a charm!

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I was able to get an original Martin waterkey from Tabor as well, but it was missing the threaded rod that holds it in the saddle, so in the interest of time (trying to get this done before that alumni game), I just put on a water key from a Reynolds baritone I had in my parts bin.

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So it was playable in time for the alumni game! Here are a few pictures of it next to the other sousaphones (20K's) from the other participants (the photo outside has my wife's mellophone nestled inside it):

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A friend of mine snapped a picture of me during our march down to the stadium:

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It played great (the hardest part was re-learning all the fight songs with Eb fingerings...), I got a lot of "what's that?" questions, and I had a lot of fun! This will be my go-to horn for standing gigs. I might add a 4th valve someday, but we'll see. Now I can maybe get back to my front-action Eb conversion project....

Re: 1928 Martin "Medium" Eb Helicon

Posted: Thu Oct 03, 2019 6:28 pm
by Tubajug
bloke wrote:EXCELLENT !!!

Tension bands can be removed, you can file down the closure surfaces with a thin file (to avoid ruining the curvature), clean up the solder surfaces, and reinstall.
Thanks!

This one is a separate tension band that goes around the tube that the neck inserts into. I already shaved off a bit of it (as you mentioned), but it still doesn't pull the tube tight enough to keep the neck stable. I wonder if the tube itself got expanded from too much yanking around on the neck. The hose clamp works, and isn't very noticeable since it's "silver" like the rest of the horn.

Re: 1928 Martin "Medium" Eb Helicon

Posted: Fri Oct 04, 2019 11:05 am
by iiipopes
I have also either played or owned all the bits in the picture; #4 is definitely an Olds-Reynolds bit. I had two identical to the picture when I owned a Reynolds fiberglass souzy.