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Conn 22K Repair Question

Postby TUbajohn20J » Mon May 14, 2018 2:41 am

I just bought an original style 22K from 1965. The one with the fiberglass 4th branch, and lower #3 slide brass brace fastened into the aluminum lug screwed into the fiberglass body. Well that brass brace is broken off into the aluminum causing the valve section to be real floppy . I can't come up with a good way to fix it. I know this is a common problem on the old style 22K's. I'm just curious about what everyone has done to repair this. Edit* Pic in thread by bloke. Deleted my picture because they were so big nobody could see them.
Last edited by TUbajohn20J on Mon May 14, 2018 10:08 am, edited 1 time in total.
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Re: Conn 22K Repair Question

Postby Donn » Mon May 14, 2018 9:27 am

That's messed up. Not the 22K, the picture. My browser reports an image size of 2925x5248, which it can't properly display even on its own page for some reason.

You should reduce your photo way down, save it back to your photo hosting site and edit your post to point to the smaller image.

I can't advise you on how to do that if you're using Microsoft Windows. On Mac OS X, the included "Preview" application does it, under "Tools". Resize it so the long side goes from 5248 to 1050. That's as much as anyone's going to see on a browser page anyway, it will be 1/20 the data for everyone to transfer, and it will work better.

If you use the camera only for images that you share like this, it may give you the option to reduce its image size, for all future pictures.
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Re: Conn 22K Repair Question

Postby bloke » Mon May 14, 2018 9:57 am

This is NOT the most elegant (and probably not even the best) solution, but it's simple enough, and probably something you can do at home.

- Drill a curved hole all the way through the aluminum by drilling down from the top and drilling up from the bottom.
- Pick up a piece of 3/16" (or whatever is the matching diameter of the Conn brace) diameter piece of brass rod.
- Thread the bottom two-or-so inches of the brass rod to screw on to a common-thread nut in that diameter range that can be easily bought.
- Screw one nut (and a washer as well) all the way to the top of the threads in the middle of the brass rod.
- Bend the threaded end of the brass rod somewhat, and pound it down through the hole in the aluminum with the upper nut and washer in place.
- Install the lower washer and nut, and tighten.
- Bend the upper (smooth) end of the brass rod to line up with the female flange on the lower slide of your third slide, cut it to the proper length
(if not already) and tighten the screw down on it. Just before insertion (when you can tell just where to do it), file an intention into the brass to accept the screw,
which will make the connection more secure.

Image
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Re: Conn 22K Repair Question

Postby bloke » Mon May 14, 2018 10:18 am

Otherwise, you can drill out the top portion of the aluminum, tap a BIG-@$$ female thread into the aluminum (as the existing hole - with the broken-off part stuck in it - is already pretty large), and screw something into those threads, but...
- you'll have to buy a large tap + a large die (more expensive than my previous solution, which only involves buying a small die).
- you'll be relying on the "meh" strength of the aluminum female threads to support your appliance, and
- you'll probably have to silver braze some 3/16" diameter brass rod to the top of your appliance.

I tried to come up with a
- no brazing
...and...
- lower cost of materials

solution for you.

==========================================


The "restoration" solution would be to drill small hole into the stuck male threads, screw in a left-handed thread extractor, remove it from the aluminum, and braze the recovered piece of threaded brass back on to the bottom of the factory appliance.
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Re: Conn 22K Repair Question

Postby TUbajohn20J » Mon May 14, 2018 10:25 am

Perfect! Thanks Bloke. I know I could do the first method you suggested. That repair seems simple enough and makes more sense than what I had in mind. I don't know how to braze either so I probably won't attempt to learn how to on this horn. I was going to go to home Depot and buy some kind of clamp and figure out how to clamp the 3rd valve tube down to that fiberglass branch. I like your way better. I'm going to attempt this and will post back here when done. Wish this was a later model 22k with the brass 4th branch but I know once I fix this it is going to be handled with care.
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