Patching a Bell Crack: Restoring an Antique French Horn #4 

I never knew patching the bell took so much effort ! Thanks for sharing !

Art, that patch looks remarkable!

Another thought....ammonia leaches zinc from brass, so I am wondering about mitigation for THAT after the ammonia is used to neutralize the flux......? A quick exposure of ammonia should not be a problem, and the ammonia evaporates quickly in free air, but I have read on brass instrument forums about ammonia that wicks into tight seams, and potentially remains un-evaporated long enough to do some damage to the brass. I don't have any real data or personal experience with this, however.

When I still worked in brass restoration, my flux bottle had a needle to better direct the flux to where it needed to be; in this video, it looks like a lot of flux is going anywhere but where it needs to go. My shop also had a steel roller on a wooden handle (I forget the tool's name) that was ideal for rolling brass around the bell wire, would have made quick and accurate work of what is being done in this video. I also had a wet sponge, along with another flux bottle with needle containing water, to quickly cool an area that had just been tack soldered.

Have you tried using liquid polishes? They tend to work much better when hand buffing and remove even less material that rouge.

RIP to the brave trombone who donated their life to music 🎶

Why didn’t you just hard soldered it and then file it down? I’ve had these situations before and it came out almost unnoticeable

Art, if you think you can fix the lathe with just a left hand acme nut, look here. www.mcmaster.com/brass-acme-nuts/acme-lead-screws-and-nuts/

to make an acme screw, look up "This Old Tony" his you tube channel has a lot of great machining videos

Master is using gas in the torch?

You know when there are houses with arched windows or porches and they get sided, they always seem to have an edge around the curvature that is not smooth, instead, it is cut into notches and just kind of shoved on so that it looks a mess and is no longer a curve. When I see you affixing this curved piece of metal, I can't help but that people who want their houses with arches sided, they'd be better off hiring a skilled band instrument repair person than someone who sides houses. Certainly you could figure out how to make a nice curve around an arched window.

I’m sure Keith Rucker of Vintage Machinery can help you with your lathe he is also on RU-vid

teacher I think there is a pliers for that. or a round-headed pliers

Since this instrument already had one patch, but the crack had exceeded that boundary, does it ever make sense to first remove the old patch and replace it with a larger one?

I had a thought about your "loose" valves. The analogy in my mind is that of piston rings that seal the cylindrical piston within the engine block. The piston is not flush to the edge but the piston ring seals it. Could you solder thin rings to the valve assembly that could seal tighter and not try and increase the diameter of the whole valve ?

😳😳😳