B&S Broken stop arm

Projects, repair topics, and Frankentubas
Post Reply
pesante
Lurker
Posts: 2
Joined: Tue Dec 26, 2023 4:32 pm
Has thanked: 2 times
Been thanked: 0

B&S Broken stop arm

Post by pesante »

I have what is likely a B&S 101 bought from Dan Schultz a few years back. A prior owner had the S-links replaced with ball and socket linkages. It's been an excellent horn.
During the Christmas concert, however, a propagating crack in the second-valve stop arm gave way late in the show. Surprise! I limped through with combination of alternate fingerings, manual manipulation of the second rotor, and leaving out a few notes ...
I'm looking for some advice on how to get this horn functioning again. I have other horns, so time's not a factor.
I figure my options are hunt and beg for a replacement (happy to post measurements if anyone thinks they have a match) or repair it. I have several thoughts on possible repairs including (but not limited to):
1) Removing more material around the broken area and mount the linkage on the (now lower) surface above the stop-arm pin (inelegant, putting it mildly)
2) Machine a piece of brass stock to fill the gap that was cut away originally for the S-link and silver solder it and the broken piece to the stop arm

In fact, I'll probably make some brass gap fillers for the other rotors anyway. The one that broke actually had small washers in its gap. The others do not; I need to remedy that.
Pictures are below.
Attachments
BnS_StopArm2_small.jpg
BnS_StopArm2_small.jpg (191.28 KiB) Viewed 225 times
BnS_Rotors_small.jpg
BnS_Rotors_small.jpg (180 KiB) Viewed 225 times


User avatar
LeMark
Site Admin
Posts: 2836
Joined: Wed Aug 12, 2020 8:03 am
Location: Arlington TX
Has thanked: 77 times
Been thanked: 819 times

Re: B&S Broken stop arm

Post by LeMark »

Looks to me like someone could silver solder it back together.

And yes, I would use longer cap Screws to make sure both round plates are engaged. Less torque, less chance of something breaking
These users thanked the author LeMark for the post:
pesante (Wed Dec 27, 2023 8:36 am)
Yep, I'm Mark
User avatar
bloke
Mid South Music
Posts: 19296
Joined: Thu Aug 13, 2020 8:55 am
Location: western Tennessee - near Memphis
Has thanked: 3845 times
Been thanked: 4088 times

Re: B&S Broken stop arm

Post by bloke »

I believe I could repair that, but repairing it would be easier than typing all the words that I would need to type here to describe the repair, and typing those words wouldn't repair it.

Just to be clear, I believe quite a few other people could repair it as well.
These users thanked the author bloke for the post:
pesante (Wed Dec 27, 2023 9:18 am)
pesante
Lurker
Posts: 2
Joined: Tue Dec 26, 2023 4:32 pm
Has thanked: 2 times
Been thanked: 0

Re: B&S Broken stop arm

Post by pesante »

Thank you, sir.
I'll be in touch.
User avatar
bloke
Mid South Music
Posts: 19296
Joined: Thu Aug 13, 2020 8:55 am
Location: western Tennessee - near Memphis
Has thanked: 3845 times
Been thanked: 4088 times

Re: B&S Broken stop arm

Post by bloke »

Anyone who can hold that in place so as the screw lines up - and probably using the screw to line it up (along with a skinny little spacer such as a little piece of hollow brass tubing) - can do that for you, and there's probably someone that's reasonably local. If you need to mail it, whatever.
Post Reply