Iíve got a Stewart Horn 114A that kept locking up. I didnít know what the problem was. Once Iíd start to disassemble it, it would release and work again (before I could see what was wrong). Tapping the handle would work sometimes... big mistake. I eventually cracked a couple teeth from the largest gear.
Has anyone disassembled and repaired one before. What am I getting myself in to? [Besides, before I can do that, I need a replacement gear.]
Can't help on replacement gear.
Have opened a few, and most have internal coil spring that collapses and rebounds the handle back up. A bit of light oil or Vaseline helps the clockwork gears. When dry, things stick. Or if the adj. screw to the ragged edge roller that pushes the diaphragm is overtightened, can bind the works.
Couldn't always get this horn to rebound, so added a 'helper spring' to do the work
Thanks, Dan. At one point I cleaned the gears and then re-applies heavy grease. I believe that complicated things. If there was grit inside, it likely stuck to the gears and got caught up even easier. Live and learn.
I loosened that sound plate screw to allow it to work easier and that helped the action, but the grit didnít care. I guess thereís a chance that the gear had already been damaged and it wasnít in a position where I could see it.
Iím curious to see what it will take to get that gear set out of the housing. Iím hoping a mechanism will show on line soon where I can just replace the set. If I could just replace that gear, life would be okay, but Iím guessing disassembling that sucker is more complicated than it looks.
I wonder if you could silver solder a new tooth in the gear?
Look for a sympathetic clock repairman in your area. He will be able to disassemble it if it can be disassembled, and if the gear is not Zamak, should be able to replace the damaged teeth. Sometimes, mechanisms like that often have shafts staked into place, and opening holes to extract them result in breakage. I personally do not know how this particular device is assembled. Expect to pay more than the horn is worth, though, unless he's so sympathetic that it is his week's charity case.
I was wondering about Ďrebuildingí the tooth, David, but itís likely beyond the paygrade of a hack like me...
And then the issue that Scott mentioned is ringing in my ears... Iím going to get adventuresome in the coming days and start attempting to disassemble it reeeeeeeeeeally slowly.
Just going to wait it out to see if someone out there may have a golden trick for me.
I was lucky enough to stumble on a trick for changing a tire/tube and hope someone has a similar one for this...
...or eBay shows up with the guts to one soon. There was a perfect match that showed up there and sold for dirt (it was just the rear casing and gears)! but my problem didnít appear til after it sold.
if you "go for it", be aware that many assemblies such as this actually have the gear assemblies pressed onto a tube or shaft that is drilled through. The assembly is placed between the mechanism's bearing posts and then a shaft is either slid or pressed through the gear/tube assembly. The bearing posts then are staked to keep the shaft from sliding out. Under no circumstances should you ever consider bending the posts to get the gears out. That will end in breakage.
Looks like weldable teeth from the picture.
Thank you Scott!
I noticed that it looked like someone scored it to create a swage fit. I'm guessing I'll have to pop the shaft to get it out.
I'll have to take a ton of pictures and post them whenever I get around to it.
Kep, I'm a geek consulting engineer so watching me weld might be like watching replays of Joe Theisman's ankle injury over and over again! You know how it's going to end and it's going to end really bad, but you just gotta keep glancing at it. Hahaha