Hermle 341-020 Chime gear. On the rear.

[disciple_dan]

Hey guys, disciple dan here.
I wasn't sure what this gear is called but it's the one on the rear of the arbor that the Chime locking gear is on in the front. Chime control gear maybe. Please correct me. Here's a pic.

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It has a nut on top. My question is does it screw off? I can't get it turn even with much force. Is it pressed on? I've seen one of these before when I was just getting started and I couldn't find any info on it so I just cleaned it the best I could in place.
This movement has an L stamped on the back so it's a 2000 model.
OK, thanks for the help, Danny

[willofiam]

Dan, I have never seen this. my first impression is that someone made the threaded pc..I see threads that go into the wheel bushing...dont think the manufacturer would do that.....possibly solder? loctite? who knows.....usually these would have a E-clip of some sort BUT I could be wrong, maybe someone else has seen this set-up???

[disciple_dan]

Wow, I thought sure you would have seen this set up. I have seen one other in my three years of clockwork.
The customer said she bought it new in 2000 and has had it ever since. ??
Well, as I looked at it very close, it looks to be pressed on. You know how they sometimes put flutes running parallel with the arbor and press something on. Maybe flute is not the right nomenclature. They punch up some high spots all around and press fit something on it.
Anyway, I can see a little of that showing under the gear close to the plate. I think maybe the nut was just to keep it on. Seems a little extreme to me.
Yeah, for more work than a simple clip as normal.
No matter now, it has so much wear I have suggested it be replaced.
Now that I am replacing it I will have a chance to learn how it was put on. I would still like to hear if anyone has seen one like it.
Well, thanks again William for your post. Y'all take care now, Danny

[willofiam]

Oh..O.K. I was thinking it was a intermediate wheel that was mounted on a post and turned freely. I guess that one is on the actual arbor and pressed onto it....still doesnt look right to me though but that doesnt really mean much. I would have assumed that that wheel would be able to be adjustable on the shaft. If your able to Dan can you give us some photos of it coming apart so we can see the set up? Thanks...Have a great day.

[disciple_dan]

I sure will, William.
If this is some rare or not so much used method I'd love to share what I learn from it.
You know, I was thinking about this thing. That's the gear that drives the chiming sequence. I'm wondering how you would set up the chime sequence if that gear will not turn freely on its arbor. I think you would have to make sure the gears where meshed just so like the older American movements.
Most of the Hermle's I've seen have a set screw on that gear and with the clock, at the full stop and at the first quarter (or the third quarter) hour, you turn it free on the arbor until you get the first 4 notes of the Westminster chime and then set the screw. You can't turn this gear freely.
I'm going to work on it tonight so I'll let you know what I find out.
Thanks for all your help, God bless you all. Danny

[disciple_dan]

Hey Y'all,
OK, What I found out is that the gear in reference is pressed on. I was able to put a small clamp on the top of the arbor on the gear side and push it out. You can see in the pic the knurled (or serrated might be the correct word.) that the gear is pressed onto.
My guess is that the design engineer set it up so when you had the movement completely assembled, you put the gear on the arbor and when you got the chime sequence set where you wanted it, you used the nut to pressed the gear down on the serrated part of the shaft so that it would not turn freely anymore. Just a guess.
So, That was good to know. The first one of these I saw I did not have enough confidence to try to get it apart and I just cleaned it the best I could. Now I know.
I hope this helps someone else in the future. Thanks, again, Danny

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[willofiam]

Hey Dan, excellent, thank you for the pic. It makes sense and looks like thats how it is supposed to be, funny...I have never seen that... is there an intermediate gear between that wheel and the chime barrel wheel? If so then any adjustment would be made in that area.

[disciple_dan]

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I'm not sure what is meant by "intermediate gear".

[disciple_dan]

I see. So, if that gear would not turn freely on its arbor, with the movement all set up, you could take the middle gear off, turn the bottom gear that turns the chime barrel to set the sequence and then reinstall the middle gear and you would be good to go. Wouldn't that work?

[willofiam]

Right...that drive gear does need to be mounted to that arbor (somehow) and turns with the the arbor to drive the hammer assembly....after that gear is mounted and secure you should be able to make adjustments like you mentioned.....sorry for the confusion at the beginning of your thread... when I mentioned a e-clip I was wrong....you had mentioned that you have seen those with a set screw on the side of the collar, you were right...Thanks Dan have a nice weekend.

[disciple_dan]

William, thank you for all the good help.
I learned a lot.
Have a great holiday and thank you to all who served and died for this great country.
Danny